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Common Materials of Cookware

by Michael Chu
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Over the last year, I've received several requests to write an article on cookware. This is a huge subject, and I've been struggling to figure out a way to present the information accurately and concisely. I decided to divide the information up into separate articles and focus this one on some common materials used in the construction of cookware. I also had to decide how much science and math to include. After some thought on the subject, since this site is called "Cooking For Engineers" and not "Cooking for Physicists", I've decided to include enough information that my readers will grasp the concepts without actually doing any derivations (perhaps this could be a future article). Also, since this article is a bit long and relatively complicated, if I've made any mistakes, please let me know so I can correct them as soon as possible.

The selection of pots and pans can be a complicated affair. The shape of the cooking surface and handle(s), materials used in its construction, the intended purpose of the utensil's design, and its flexibility of use in the kitchen all are important factors in choosing cookware. Understanding the materials used is a good first step in understanding how cookware works and what factors may be important to your cooking style.

Basic principles
The purpose of cookware is to impart energy to ingredients. In America, the energy comes mainly in two forms: burning natural gas or propane gas and electrical resistivity. In both methods, the source of the heat is not uniformly spread over the pan. In a gas stove, the gas come out at regular intervals and forms a ring of individual flames. The heating elements of an electric range are designed to cover as much area as possible, but still have patterns (usually spirals) where there is no heat. Because the heat is not applied evenly, the cook must be aware of this and either compensate with cooking technique or through cookware.

High quality cookware should not only be durable, but also take the energy from the heat source and effectively transmit this energy to the ingredients. There are several factors that affect this capability. The two most important factors are thermal conductivity and heat capacity. Almost all discussions concerning the materials used in cookware are focused on these two factors.

Thermal conductivity
In short, the thermal conductivity of a material is how readily that material absorbs and transmits (releases) energy. When the fire or heating element of a range comes in contact to a pan, the energy from the heat source is transmitted to the pan. This increases the internal kinetic energy of the pan (commonly called "heating up"). The heated material then transmits the energy to nearby materials that are at a lower average molecular kinetic energy level (at a lower temperature than the material). The higher the thermal conductivity of the material, the faster it will heat up and also, the faster the heated area will spread to unheated areas of the same piece of material.

For example, if we placed a large sheet of stainless steel (fairly low thermal conductivity as cooking materials go) on a burner and turned on the burner, the area directly under the burner would get hot while the rest of the sheet slowly heats up. The burner imparts heat quickly only to the region of steel directly over it. The rest of the pan heats up from the conduction of the heat from that spot. When the outer edges of the sheet have reached a hot temperature, the spot directly over the burner would be extremely hot. The figure below shows an example of the temperature of the sheet of steel over a gas burner. The hottest parts are shown in white, hot is red and cool is blue.


One solution to this problem is to make the sheet thicker. When heating a thick piece of steel (instead of a thin sheet), the bottom surface of the steel does not have the same temperature pattern as the top surface. Because the top surface is a greater distance from the heating element, the energy needs to conduct from the bottom to the top (just like the energy conducts outwards). The top surface of the steel is more evenly heated in this case. The figure below shows the thick sheet of steel after it has been sliced so the center of the front edge is where the burner heat touches the bottom of the sheet. The hot spot (white) is reduced by the time the heat conducts to the top surface of the sheet. Where the sheet is being heated, the temperature is more uniform now, but we still have uneven heating with this material.


For this reason, the thicker the steel, the less variation in temperature on the top surface. Unfortunately, low thermal conductivity means it a lot of energy needs to be imparted to the bottom of the steel in order to get the top hot. So a pan made of a low thermally conductive material will take a longer time to reach cooking temperatures. In fact, materials with low thermal conductivity take longer to react to any change in temperature, so the thermal response of the pan would also be slow. (Thermal response is how quickly the surface temperature of the pan reacts to when we increase or decrease the flame of the burner.)

In most cooking applications, it is desirable to have the utensil heat up quickly, not develop hot spots, and react to changes we make to the range controls. Materials with high thermal conductivity fulfill our needs because they transmit heat quickly resulting in fast response to thermal changes and even distribution of the internal kinetic energy.


Here is a list of some common materials used in cookware and their respective thermal conductivity:
MaterialThermal conductivity
Copper401 W/m*K
Aluminum237 W/m*K
Cast Iron80 W/m*K
Carbon steel51 W/m*K
Stainless steel16 W/m*K


Heat capacity
The amount of internal kinetic energy stored in a material can be referred to as it's heat capacity. This isn't the same thing as temperature, which is the average molecular kinetic energy within the material. For example, a kg of water at 100°F contains more energy than a kg of steel at 100°F. While thermal conductivity describes the materials ability to absorb energy, heat capacity is the amount of energy that is needed to raise or lower the temperature of the material. The molecular composition of some materials is such that as they absorb energy, much of it gets converted into potential energy and only a small amount increases the molecular kinetic energy (water is a common example). Other materials, like most metals, increase their molecular kinetic energy readily and do not store much of the absorbed energy as potential energy. The heat capacity of a material is proportional to its mass. So, a 2 kg piece of steel has double the heat capacity of a 1 kg piece of steel (make sense, right?).

What this means is that cookware made of materials with high heat capacity, will take longer to heat up, but will also have a significant amount of energy stored up when it is hot. When energy is pulled out of the material, the temperature of the material will lower slowly when compared to materials with low heat capacity. Cast iron is often cited as an example of a high heat capacity cookware material. The specific heat (the heat capacity of a material for a given mass) of cast iron is half of aluminum's specific heat, but because cast iron cookware is generally several times the mass of aluminum cookware, it has a much higher heat capacity.

The thickness of metals used in the construction of cookware are often sited by the manufacturer (for example, 3 mm aluminum), but since heat capacity is a function of the mass of the material, density must be known to make comparisons between cookware of different materials.
MaterialSpecific HeatDensity
Aluminum910 J/kg*K2600 kg/m3
Stainless Steel500 J/kg*K7500 - 8000 kg/m3
Carbon Steel500 J/kg*K7500 - 8000 kg/m3
Cast Iron460 J/kg*K7900 kg/m3
Copper390 J/kg*K8900 kg/m3


Looking at the table above, if you multiply specific heat with density, you'll find that the heat capacity per unit volume of steel, cast iron, and copper are about 1.5 times that of aluminum. This means, to achieve the same heat capacity in an aluminum pan as in stainless steel pan, the aluminum pan needs to be 1.5 times as thick (assuming the other pan dimensions are the same).

Pulling it together: thermal diffusivity
If you've been paying attention, you'll realize that I've misled you when I discussed thermal conductivity. Thermal conductivity alone does not determine how fast the pan will heat up (and also how evenly it will heat). In fact, the heat capacity plays a role in determining this as well. Wouldn't it be great if we had a single number that told us at what rate heat would transfer through and spread out in the material? There is, it's called the thermal diffusivity of a material and is simply the thermal conductivity divided by the unit heat capacity (specific heat times density). Let's take a look at how the materials stack up:
MaterialThermal diffusivity
Copper120 * 10-6 m2/s
Aluminum100 * 10-6 m2/s
Cast Iron22 * 10-6 m2/s
Carbon Steel14 * 10-6 m2/s
Stainless Steel4.3 * 10-6 m2/s

Without additional calculations based on the heat conduction equation, there is very little that we can do with this table of values, except compare the materials against each other. It is clear, however, that the best performing materials (in terms of dishing out energy) are copper and aluminum. This leads us to our final consideration: reactivity.

Reactivity
Not only do we have to concern ourselves with the thermal properties of materials, but we need to make sure that the materials we use in our cookware do not harm us or adversely affect the taste of our food (you decide which is worse). For this reason, in addition to the high thermal diffusivity, we would also like a non-reactive material. Unfortunately, both copper and aluminum react readily to foods. (Copper, when ingested in quantity or consistently, can cause liver, stomach, and kidney problems as well as anemia. Also, aluminum has long been suspected of contributing to Alzheimer's disease. Oh, every cookbook mentions, at this point in the discussion, that the occasional foamed egg white whipped in a copper bowl is not enough to harm you - but refrain from cooking every day on exposed copper.) Stainless steel, the least reactive of all popular materials used in cookware, also has the worst thermal diffusivity.

It seems that today, physics is not our friend. But, through the magic of cookware companies wanting to find ways to charge us lots of money, solutions have been devised to enable us to enjoy cookware made of materials with high thermal diffusivity and low reactivity. By combining the non-reactive surface of stainless steel with the thermal properties of copper or aluminum, you get the best of both worlds. There are several variations on this theme: steel- or tin-lined copper, stainless steel with aluminum or copper disk, stainless steel cladded aluminum, and stainless steel cladded copper. The table below summarizes my subjective assessment of the effectiveness of various material combinations (they are listed in order from most effective to least):
RankCompositionComments
1Copper with tin liningHighest response; tin lining can be finicky can be susceptible to melting; copper exterior requires more care
2Copper with stainless steel liningCopper exterior requires more care but imparts the utensil with copper's excellent thermal properties
3Aluminum with stainless steel liningThick aluminum provides excellent thermal response to thin steel interior
4Copper fully clad by stainless steelCopper layer may be thinner than copper with stainless steel lining; exterior and interior are durable and easy to maintain
Aluminum fully clad by stainless steelAluminum layer may be thinner than aluminum with stainless steel lining; exterior and interior are durable and easy to maintain
Aluminum with stainless steel lining and copper exteriorSame performance as cladded aluminum, but with the difficulties in maintaining copper
5Stainless steel with copper diskCurved edge of the bottom causes the disk to not come into full contact with the complete bottom of the pan resulting in inferior heat conduction as compared to cladded copper
Stainless steel with aluminum diskSame as stainless steel with copper disk


Previously, I mentioned that cast iron has a large heat capacity as compared to the other materials (mostly because of the mass used when making the cookware). Because of this attribute, cast iron gets a special place in the kitchen. When the cooking task requires the ability to maintain consistent heat (and ample amounts of it), nothing beats cast iron. Because cast iron can react with acidic foods and ingredients that are cooked for a long time, cast iron cookware is seasoned - a process by which layers of fat are slowly cooked into the porous iron until the fat polymerizes forming a protective barrier (and makes the utensil relatively non-stick).

Common materials and how they compare
Now that we've looked at the important properties in selecting cookware material, let's take a look at each of the common materials used in cookware.

Copper
DescriptionCopper is a soft (scratches easily) but durable (will last a lifetime) material that has great thermal properties. The material is prone to oxidation but with care, will retain its beauty indefinitely.
Pros
  • High thermal diffusivity
  • With enough thickness, pans heat extremely evenly
  • Extremely responsive
Cons
  • Heavy
  • Extremely expensive
  • Copper surface can tarnish or scratch
  • Pan may cool too fast after removal from heat (due to extremely high thermal conductivity)
  • Cooking directly on copper may result in undesirable levels of copper intake
Best uses
  • When lined with tin, nickel, or stainless steel, excellent for all stovetop uses.
Care
  • Hand wash with a non-abrasive detergent and hand dry
  • Regularly use polish on exposed copper to preserve shine
Examples

Aluminum
DescriptionPlain aluminum utensils are low-cost, light-weight, and thermally responsive - but it's reactive. Teflon coated aluminum utensils are low-cost and both non-stick & non-reactive. Anondized aluminum has been treated to develop an aluminum oxide (extremely hard and non-reactive) coating on the surface of the utensil. Clad or lined aluminum has had stainless steel bonded to the interior of the utensil to form a non-reactive surface.
Pros
  • Extremely low cost if plain or teflon lined; moderated priced when anondized
  • Great thermal properties
Cons
  • Very expensive if stainless steel lined or clad
  • highly reactive to acid ingredients (and somewhat reactive to alkaline as well)
  • Lower density may require thicker construction to increase heat capacity
  • Unless anondized or lined or clad with stainless steel, may warp under high heat
  • Unless anondized or clad, aluminum is prone to scratching.
Best uses
  • Plain aluminum - good for non-acid foods, like boiling stock or cooking pasta
  • Coated aluminum - excellent for all purposes if aluminum is fairly thick
CareHand-wash with a mild detergent and washcloth or sponge.
Examples

Cast iron
DescriptionCast iron is composed on iron, carbon (more than carbon steel), and trace elements found in common clays. The iron is melted down and poured into a sand or clay mold to form the utensil. Enameled cast iron has a thin but durable nonreactive layer of glass fused to the surface of the utensil.
Pros
  • Plain cast iron is low cost
  • Manufacturing process results in thick and dense cookware for unparalleled heat capacity
  • Thickness also results in even heating
Cons
  • Enameled cast iron can be expensive (although some are moderately priced)
  • High heat capacity means the utensil takes longer to heat up
  • Although extremely hard, can crack or fracture if dropped or thermally shocked (pouring cold water into a hot pot)
Best uses
  • Traditional woks (plain cast iron), skillets, Dutch ovens
  • Southern cooking
CarePlain cast iron should be seasoned before first use and as needed. A seasoned utensil should receive minimal contact to soap or detergent. Wash by soaking in warm water for a few minutes and repeatedly scrubbing with salt and rinsing until salt remains white (usually one scrubbing is does it). Dry with a cloth and heat over low heat briefly to evaporate all moisture. For enameled cast iron, hand wash in hot soapy water.
Examples
  • Lodge Logic (low cost cast iron)
  • Wok Shop (low cost cast iron traditional Cantonese wok; this wok is awesome, but its rounded bottom works best on gas stoves)
  • Le Creuset (expensive enameled cast iron)

Carbon steel
DescriptionCarbon steel contains less carbon than cast iron and is formed and pressed from sheets instead of being casted. It can be annealed (heating the metal until its molecular structure realigns to alleviate internal stresses and then specially cooled to preserve the new structure) to form blue steel (or black steel), a harder and less reactive material. Carbon steel can also be enamel coated.
Pros
  • All variations are usually low cost
  • Fast seasoning process for carbon steel; enameled carbon steel and blue or black steel does not need seasoning
Cons
  • Poor thermal properties means slow heat up and uneven temperatures.
  • Thin and light (this might be a pro for some people) which results in very little heat capacity
Best uses
  • Fry pans, saute pans, woks
CareShould be seasoned before first use. Care for as if it was cast iron. If desired, pan can be washed in soapy water, scoured, and reseasoned quickly (15 minute seasoning) because of its less porous nature than cast iron.
Examples

Stainless steel
DescriptionMixing steel with chromium and nickel (18/8 stainless steel is 18% chromium and 8% nickel while 18/10 has 10% nickel) produces a corrosion resistance steel that is both hard and easy to maintain a shine. Disks of copper or aluminum can be fused to the stainless steel cookware to enhance its thermal properties. Stainless steel can also be used to line copper or aluminum utensils as well as cladding aluminum or copper (see aluminum and copper cookware summaries above).
Pros
  • Plain stainless steel and stainless steel with aluminum or copper disks are low cost to moderately priced
  • Shiny surface makes it easy to see how your food is browning
  • Corrosion resistant and easy to clean
  • With a thick aluminum or copper disk or clad around a core, stainless steel becomes one of the best materials to cook in (not just for its thermal properties, but as well as durability, ease of care, and visual control of cooking - all the benefits of stainless steel with very little of its drawbacks)
Cons
  • Plain stainless steel: worst material to cook on (in terms of thermal properties)
  • Salt may cause pitting over time unless added to boiling liquid
Best uses
  • Plain stainless steel: boiling water (steaming is okay) and non-cooking related tasks (mixing bowls, storage containers, etc.)
  • Stainless steel with copper or aluminum disk: great for all purposes if disk is well bonded and of a fair thickness
CareHand wash with mild detergent. Use gentle abrasives as needed.
Examples

My personal favorites for cookware materials are stainless steel clad aluminum or copper and cast iron (for skillets and woks). The stainless steel clad utensils perform well, are easy to clean, and look beautiful. Of course, not all stainless steel clad aluminum (sometimes called tri-ply or five-ply depending on construction) are the same. All-Clad has definitely earned their reputation as quite possibly the best general use cookware money can buy, but it's a lot of money to be spending. All-Clad rarely goes on sale, but other reputable brands, such as Calphalon, have clad lines as well - and they are more likely to have their product lines go on sale. Keep checking the Cooking For Engineers Deals Blog to see when deals do come up.

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Written by Michael Chu
Published on July 15, 2005 at 12:22 PM
143 comments on Common Materials of Cookware:(Post a comment)

On July 16, 2005 at 11:36 AM, Matt (guest) said...
Hi Michael,

Excellent post. I've been wondering recently whether to upgrade my cookware... and to what. I'm using a Viking saute pan at the moment, which i believe is very thick stainless steel with an aluminium base... but i find it takes so long to heat up that i often prefer cooking with my cheap K-mart brand frying pan...

After reading your post, it's confirmed a number of thought's i've had... in regards to heat transfer and capacity. I'm thinking a nice Mauviel saute pan would look great on my stove top.

Cheers :)
Matt


On July 16, 2005 at 12:01 PM, eesh said...
Subject: Teflon
Hi Michael,

I was hoping to see something about Teflon (Or any kind of non-stick coating), as well.. How it works, care it requires, etc. Will you write something about it in the future?


On July 16, 2005 at 01:37 PM, an anonymous reader said...
Farberware used to make aluminum-clad stainless steel cookware which had a a much thicker aluminum layer than the products they are now producing.

If you live in a metropolitan area you can often find them at garage sales -- and at 50 cents to a couple bucks per pan, this excellent cookware is a steal.

Often you can find the older stuff on eBay, as well. I recently puchased a huge skilllet, with lid, of this vintage Farberware for about 15.00.


On July 16, 2005 at 06:58 PM, Michael Chu said...
Subject: Re: Teflon
eesh wrote:
I was hoping to see something about Teflon (Or any kind of non-stick coating), as well.. How it works, care it requires, etc. Will you write something about it in the future?

In the future, I will have a (shorter) discussion on non-stick cookware. My current problem is that I can't seem to get enough info on the newer non-stick solutions (Scanpan, etc.) and I'd like to include those as well.


On July 16, 2005 at 08:23 PM, Adam Fields (guest) said...
Subject: cybernox
Definitely include cybernox in that list, if you can get any info about it.

I have a few cybernox pans, and they're great, but I have no idea what they actually are.


On July 17, 2005 at 05:00 AM, Ned Konz (guest) said...
Subject: Aluminum probably not suspect in Alzheimer's disease...
At least according to the Alzheimer's disease association, there doesn't seem to be a convincing link between aluminum and Alzheimer's disease.

Of course, I don't really like the taste of aluminum in my foods...

However, many of the non-stick coatings outgas irritating or toxic gases when heated strongly (which those of us who stir-fry a lot tend to do). These gases can sicken people and kill birds.


On July 18, 2005 at 05:03 PM, Streever (guest) said...
Subject: Teflon
Teflon certainly isn't a good material to cook on...you lose so many wonderful cooking techniques (such as deglazing...) & the health risks are many.

Teflon is a persistent chemical.


On July 18, 2005 at 07:18 PM, mole6e23 said...
Subject: Stainless clad cast iron
You didn't seem to mention stainless clad cast iron (unless I missed it). My mom has a set that she bought in roughly 1965 that are some of my favorite pans to cook with (she bought a 7 pan set from a door-to-door salesman for $300 which was close to their monthly income at the time!) Except for some problems with the handles, the pans still look almost new even though they've been through three children and numerous dishwasher cycles.

Are these types of pans still available?


On July 19, 2005 at 01:05 PM, Ht354 (guest) said...
Subject: Cookware Purchasing
I read the review with great interest. Although the research is reflective of the results found elsewhere, ie Consumer Reports/Cook's Illustrated, what is left out is the all important human factor.

How does the cookware feel when you handle it? Does the handle get Hot? Will it take hours a week to keep clean/looking nice? The easiest way to answer the question is to recommend any verison of the "All Clad" cooking tools. They come in both regular and nonestick, handles stay cool, they are comfortable, conduct heat well and evenly considering the Stainless Steel quotient, and will be the last set of pots & Pans you'll ever buy. Oh yea, "all Clad" is always rated in the top two by Consumer Reports/Cook's Illustrated etc., not to mention most major cooks without a cookware deal use it also, just watch the food network/TV.

Don't get me wrong, you can go with Faberware, and TFal and so on and so on, but you'll replace it every 5 to 7 years, and eventually pay more in a lifetime than if you bought "All Clad" up front.


On July 19, 2005 at 01:38 PM, Shalmanese said...
Subject: Egullet link
Hi,

Check out the egullet understanding stovetop cookware for another excellent take on this topic.


On July 19, 2005 at 05:46 PM, John Elledge (guest) said...
Subject: Cookware
No cookware does everything well. My opinion is that each piece should be selected for a specific technique. For example stainless with a thick disk bottom is good for sauce pans but poor for an omelet pan for the same reason: the sides don't get hot. Aluminum or copper stainless ply makes for a great skillet but would tend to radiate heat out the sides if used for a saucepan. I have some All-Clad stainless and like it's cooking performance but dislike the riveted handles (the rivets on the inside of the pan are difficult to clean) and the polished stainless exterior looks good when new but scratches if you use a Scotchbrite pad on it. I am now using Demeyere Apollo (stainless steel) sauce and saute pans and like the Silvinox finish and the welded handles. They do look a bit industrial though! I enjoyed the article, thanks for writing it.


On July 20, 2005 at 02:49 PM, RJ Keefe (guest) said...
Subject: All-Clad
All-Clad cookware may be expensive, but to all appearances it's eternal. I expect that people will be inheriting the stuff pretty soon, and I wonder what All-Clad plans to do about this, business-model-wise.


On July 20, 2005 at 09:45 PM, dakirw (guest) said...
Subject: Cookware Safety Links
Some cookware safety links:

Cookware Safety
FDA article

Might be a bit out of date, but still handy


On July 22, 2005 at 06:03 AM, mmcneill said...
The cookware I use most often is a 5 by 7 by 1.25
inch casserole pan from Nordic Ware. It has
badly applied non stick that I am pleased to see
is rapidly flaking off. It is steel so will
work on my induction cook top. The greatest
use is for baking between the smooth hot
upper and lower plates of my Griddler panini griddle.
It makes beautiful casseroles, bakes a roast, or heats frozen entres.
If I need a lid
another pan inverted and held on by two
one inch paper clamps that squeeze easily around
the two rims.
It has many uses except for microwaving.


On July 26, 2005 at 03:50 AM, Quelyn (guest) said...
Subject: Forgot a type of cookware
Enamel clad Aluminium You might be more familiar with one of the better brands called Graniteware. Usually dark blue with greyish flecks.

This type of cookware is thin aluminium coated with enamel inside and out. Used by our Grandmothers when cooking and still around. Relatively cheap. Usually found in camping stores or where you find home canning supplies for the larger pots.

Excellent if you want to boil anything. Horrible if you want to cook something slowly.


On July 26, 2005 at 09:06 AM, Cathy Tallmadge (guest) said...
Subject: Cookware
Some of the best cookware is availible at restaurant supply stores. I discovered a line that is like All Clad but at about half the price called Tribute, made by the Vollrath company. These stores also have the best non stick fry pans for eggs, omelets, frettattas etc. I recommend the Lincoln Wearever Ceramigard line for this type of cooking. There is no set of cookware that does everything. I use cast iron, enamel clad cast iron and even glass, depending on what I'm doing. Cookware doesn't have to match, it has to work. As for enamel clad aluminum cookware, it's good for one thing..... nothing. O.K. maybe boiling water.


On August 21, 2005 at 08:48 PM, connordr (guest) said...
Subject: Non-metallic cookware
You do not include Corningware or pyrex in your survey. I do use a Corning glass double boiler and also use itin the microwave. THe poor conductivity of glass makes it unacceptable for most other uses. I have not tried Corningware -pyroceramic- recently, but as I recall it had much the same problem. In general I find glass -pyrex- ideal for baking with the exception of slow cooked beans which do best in earthenware.
Will there be another article on what works best in an oven?


On August 22, 2005 at 03:50 AM, Chef Jim said...
As has been mentioned there's no set that will satisfy all needs. I use All-clad as my primary set, love it, does excellent job, great quality. I have a set of non-stick Calphalon that I am very disappointed with seems to wear out almost as quickly as T-fal, wearever, etc. but was far more costly. But now I'm limiting it's use to eggs and fish so no problem! I also have two non-stick Revereware sauce pans, they have pouring spouts and glass lids with strainers. These do come in handy, great for heating leftovers, sauces, etc. Also have two castiron pieces a 12in frypan and a two-burner grill/griddle. Next purchase will be Enamel over castiron dutch oven. 16Qt Stock pot is All-Clad but only the bottom is three-ply which is fine for simmering stock and Pasta Pot is inexpensive S/S with glass lid. Wore out one that I loved it had s/s lid with two vents and could cook pot of pasta with lid on and no boil overs! This glass lid only has one vent and it has to be watched for boilovers constantly, on the good side it is glass so you can anticipate better!


On August 29, 2005 at 03:19 PM, Mark Leng (guest) said...
Subject: No need for non-stick coating
Despite my wife's insistence, I had a hard time believing stainless steel would be almost as easy to clean as non-stick coated pans. I'm happy to say our All-Clad is very easy to clean, especially if you don't let the food dry on it overnight. ;-)

The worst cases have required some soaking with water and dish detergent but that's it. And there's no seasoning required, unlike cast iron.

The only thing that really stuck to the All-Clad was a melted $3 plastic steam basket. (don't ask)

Freezing, WD-40, Simple Green and Wright's Silver Cream cleaned the pan up nicely. My only hope is that I didn't damage the corrosion resistance of the stainless steel.

Does anyone know if I could have permanently damaged the stainless steel somehow?


On August 30, 2005 at 03:51 AM, jimjimjim9 said...
Stainless is an alloy from which the pan is made, not a coating ( ie teflon or anodized aluminum.

Here's a fun place to start inquiy into stainless:

http://www.corrosion-doctors.org/MatSelect/corrstainsteel.htm


On August 30, 2005 at 03:04 PM, an anonymous reader said...
Thanks Jim.

I had read about the chromium-oxide "layer" on stainless steel (see below) and wondered if I had damaged the corrosion resistance of the All-Clad, or any of its inherent non-stick properties.

I'm really out of my element here so my questions might seem a bit "daft." ;)

Is the chromium-oxide layer important for cookware? If so, does it require maintenance or special care?

Thanks.

"Stainless steel can corrode in service if there is contamination of the surface. Both pickling and passivation are chemical treatments applied to the surface of stainless steel to remove contaminants and assist the formation of a continuous chromium-oxide, passive film."

"The purpose of passivation of the surface is not only to clean and remove free iron, but to maximize the chromium content of that top, very thin "layer" of chromium oxide. (Other metals in the alloy also greatly affect this.) This gives the best corrosion resistance,"

"As you are no doubt aware, one of the attributes of stainless steel is the fact it has a built in oxide layer over it. This is in the form of chromium oxide and it is this that gives it its corrosion resistance. If you want to enhance this, you have to be careful how you do it; if you simply anodically polarise it, you will run the risk of breaking down the existing layer and dissolving out the metals. You could try putting it in hydrogen peroxide and leaving it, or better still, try electropolishing it."


On October 07, 2005 at 02:25 PM, geo said...
I am new to this forum but have been reading the excellent articles on cookware materials! Thank you! I have been ruminating for the past week almost all of my day! :shock: over which cookware set to purchase and hope someone can offer advice. I have a cast iron 5 qt dutch oven and cast iron frying pan. I am not a pro but just very interested in cooking/baking with high quality pans at a reasonable price. I read about some test that put tied for 1st place Tramolina and Cuisinart cookware. I have no other info on who did the test (read about it at Chef's Depot but no detail) I have seen at Burdines a Chef's Classic set by Cuisinart and there is a Cuisinart Multiclad which is what I was interested in and (I think) is their professional line. It has the aluminum going up the sides, too. The problem is, I have no idea how to find out the THICKNESS of the ALUMINUM. I don't know what else to do. Sale ends VERY soon on this 12 pc CUISINART MULTICLAD set which has ALL the pieces I need for $210. Any suggestions? Could the thickness of the aluminum be published anywhere or can anyone point me to any tests/awards? Supposedly, the Cuisinart line is endorsed by French chef (I think his name is) Paul Bocuse. He endorses the Chef's Classic line which has the aluminum disc only (not up the sides). I know endorsements often don't mean a thing. I am so confused. Any thoughts or advice would be appreciated.

geo


On October 07, 2005 at 04:54 PM, Guest (guest) said...
Subject: Teflon?
Nice, thorough discussion. There is more to cookware, of course, than the material, as other posters have noted.

Regarding the possible health risks of using teflon, there are none.

http://www.cei.org/gencon/019,04820.cfm

It is true that there may be some health risks caused by a chemical used to <b>make</B> teflon (namely perfluorooctanoic acid, or PFOA), but that is a problem for chemical factory workers and perhaps people who live near the factories, not people who use teflon. There is no PFOA in actual teflon.

http://www.planetark.com/dailynewsstory.cfm/newsid/29003/story.htm

Teflon itself is chemically unreactive; in fact, it is one of the least reactive substances ever discovered. If we ate some teflon, it would pass through our bodies unchanged. None of it would enter our blood stream. But even if it did, it would would not affect any of our biochemical processes, since it is unreactive. It would interact with the body about as much as a stone reacts to me shouting at it. In fact, that unreactivity is part of why it is so slippery. Maybe the subject of another article in Cooking for Engineers?

People pay lots of attention to health scares, as they should, but they often don't take time to look at it carefully. PFOA is not an "ingredient" of teflon, it is one of the chemical precursors of teflon, like oil is to polyurethane. If oil is bad for you, it doesn't mean that polyurethane is. (And in fact, high-density polyurethane is totally inert in the body just like teflon, so it is used in artificial joints and the like.)

Like EMF radiation from powerlines, this one appears to have been cooked up by trial attorneys looking to make a buck.

Karl


On October 26, 2005 at 08:10 PM, Misc (guest) said...
Subject: DDTs were great too.....
"Frying pan fumes kill canaries"
http://news.bbc.co.uk/2/hi/science/nature/3441255.stm

Admittedly, canaries are not humans, but Teflon seems to break down under high temperatures according to one group of researchers (absolutely not! says the other side - Teflon is unreactive).

It's always like this - everyone argues and there are strong motives for lying and exaggeration - but at the end of the day we're built out of the same basic stuff as canaries so I think I will give Teflon a miss - if it's killing them then it's most likely partially killing me...

(from the viewpoint of an economist in his 20s) < always important for evaluating info i.m.o - how much do they really know about x, y or z after all... perhaps not too much in my case, but I do like to think critically - I dislike selective evidence - now you have both sides to consider. ^.^

[edit] from that link posted earlier:

Although nonstick pans will wear away with hard use and particles may chip off, the Food and Drug Administration has stated that these particles would pass unchanged through your body and pose no health hazard. A coated pan heated for long periods at high temperatures will give off fumes, but these are less toxic than fumes given off by ordinary cooking oils.

Do these people ordinarily cook with crude oil or something!??!


On October 30, 2005 at 11:17 PM, Ted N. (guest) said...
Subject: Great stuff and solid advise
The info you tell reflects the experiences I have with cookware. it is accurate and on target in my opinion. I spent 20 years cooking and 5 selling cookware. all clad is good stuff but priced high, there is tri ply from cuisinart and calphalon at a lower cost. viking is great and more ample in space but way up in price. my personal favorite is the Gourmet standard tri ply, it has the best comfort with solid performance. I love the handle and the solid construction. I am not afraid of teflon but keep the heat down its not my choice for searing or high temps best for eggs and pasta. I protect the pan surface with the panjacket cover to store all my cookware that way. keep up the great info. Ted :)


On November 06, 2005 at 09:33 AM, dg (guest) said...
Subject: Cast Iron
After years of trying various combinations of expensive and more expensive aluminum, teflon coated aluminum, anodized aluminum, stainless clad aluminum etc we have gone back to cast iron for most uses except boiling. Cheap, easy to clean, bombproof, nonstick, even heating, and can be made really really hot for searing without worry. Heavy, so we just leave it on the stove.

Runner up is stainless clad aluminum, but it is harder to clean and not as nonstick, and much more expensive.


On November 29, 2005 at 10:08 PM, tg4360 said...
Subject: Tri-ply = good stuff
Thanks for the great information source.

To add a data point:

After much research and reading here and else where, I picked up the member's mark tri-ply cookware at Sam's club. I could never afford an All-clad set right off so this get's me the same performance at a great price. So far the quality and performance is right up there with All-Clad. I know I'll probably pop for something from the big "A" just for the fun of it but I'm very happy with my selection.

Reading about material and construction/performance here was a great help in my selection.

THanks!


On November 30, 2005 at 03:55 AM, hubiquitous (guest) said...
Subject: Induction cooktop vs Copper/Aluminum cookware
Thanks for the straight-up science. Bring on the physics!

I am very close to picking up a set of Copper-clad cookware from All-clad. It is copper-lined w/ stainless steel coating so it should have the best of both worlds- good heat properties and low reactivity with food. But, it will not work as good with an induction cooktop as good, old-fashioned steel or cast-iron.

There are several things I like about induction cooktops (stays cool to touch), but the biggest is it's rated efficiency. Can anyone compare the efficiency of an induction cooktop to a high-end ceramic cooktop? What about the heat properties of a good stainless steel set on an induction stove to a aluminum/copper clad set on a decent stove?

~Thanks


On December 08, 2005 at 03:11 PM, an anonymous reader said...
Subject: Stainless Steel and Chromium Oxide
For the poster who asked about maintaining the oxide layer on stainless steel, from a consulting metallurgist:

The oxide layer on stainless steels is (a) self-maintaining, and (b) very diffficult to remove. Unless you're performing electrochemical experiments in your cookware, or cooking with concentrated acids, you won't damage the stainless. If you are doing those things, the condition of your cookware is probably not your biggest problem.


On December 12, 2005 at 07:55 AM, largejunglecat (guest) said...
Subject: Stainless steel, oxide layer
The chromium-oxide layer on stainless steel is the result of oxygen in the air reacting with the chrome in the stainless steel alloy. Even if you did manage to remove it, the reaction is pretty fast (If you've ever welded on stainless steel you know how quickly the oxide layer returns), especially when the steel is heated, which is a regular occurence for a pot or a pan. Because this layer is pretty non-reactive, it actually serves to protect steel.

What makes stainless steel so much nicer than regular steels is that chromium oxide is not air-permeable, so only a very thin layer at the surface reacts. Iron-oxide, which developed when normal steel reacts in air, is much less attractive and is air permeable. As a result, a piece of mild steel can corrode all the way through.


On December 13, 2005 at 12:26 AM, largejunglecat (guest) said...
Subject: radiative heat transfer vs. looks/conductivity
Since this is cooking for engineers...

I was wondering a while back, while thinking of excuses not to clean the copper bottom of my cheap stainless steel pan, whether the better radiative heat transfer that I'm bound to get from the non-shiny, more darkly colored surface of my discolored copper is worth decrease in conductivity that I assume I will get due to the oxide layer that is causing the discoloration.

Obviosly this is assuming that I'm not concerned with the asthetic aspects of the pan, since shiny things are definitely prettier.

Anybody happen to know?


On December 14, 2005 at 03:45 PM, an anonymous reader said...
I have to say that I really enjoy cooking on my Calphalon commercial annodized alluminum pans. I got them for a real steal (90% off), but watch out for pans made in china rather than Toledo, OH. I've never used All-Clad as the price was prohibitive, and with a lifetime warranty on my Calphalon, I'll never need to.

As far as the Alzheimers thing goes. Studies have shown that the original premise was false. Doctors had been finding elevated levels of aluminum in the brains of Alzheimers patients so they naturally linked it to the disease. Now though, studies are showing that the Alzheimers may cause the elevated aluminum levels rather than the other way around, and that aluminum causes no harm to the body.


On December 19, 2005 at 05:14 PM, ken mines (guest) said...
Subject: problems with non-stick pans and induction hob
recently installed a Neff induction cooker and hob. New stainless steel pans work well, but two non-stick frying pans take for ever to heat up - in fact the smaller pan which we bought for omelette cooking is useless for this - as well as long time to heat it never gets to a high enough heat to cook quickly, as an omelette should. Has anyone else had problems with non-stick and induction (the pans are magnetic and are being sold for induction use)


On December 26, 2005 at 07:24 PM, Mike (guest) said...
Subject: aluminum and disease - rubbish
Most antacides are compunds of aluminum (eg. aluminum hydroxide). These have been sold for a long time - they're a standard therapy for heartburn, no-body considers them dangersous, and the amount of aluminum you actually swallow with antacids (excluding the calcium ones, like Tums) is at least 2 orders of magnitude greater than ANYTHING you'd ever get from cooking in an aluminum pot - like ten years exposure per teaspoon. So, if aluminum predisposed to alzheimers, people who take antacids would all be brain dead. Aluminum is HARMLESS.


On January 02, 2006 at 04:03 AM, Joe (guest) said...
Subject: yummy nonstick coating and working with bad cooktops
I was worried about this for a while when my mom continued to use a pan which was peeling. I did some research and found out dupont got teflon classified as a food additive. Though I personally stay a way from nonstick it isn't for any safety reasons.

Also, I have a horrible cook top in my apartment and often find myself doing dishes requiring searing. I can get around this using cast iron which holds enough heat that I can finish searing before the thing noticeably cools down.


On January 15, 2006 at 10:53 AM, TruthFinder (guest) said...
Subject: Aluminum Toxicity
Aluminum toxicity is a recognized medical condition.

http://www.healthy.net/asp/templates/article.asp?pagetype=article&id=1958

With use of aluminum pots and pans and aluminum foil, some aluminum leaches into food, especially with acid foods such as tomatoes or rhubarb. Cooking with fluoridated water in aluminum cookware increases the aluminum in the water and the food; still, the amounts we obtain in this manner are small in comparison with those from additives. Aluminum salts used in antiperspirants are not a major contaminant either, unless these products are overused. (Aerosol sprays, however, should be avoided for environmental toxicity reasons.) Antacids containing aluminum hydroxide can be a big source if they are taken regularly or abused, as antacids sometimes are. Some children's aspirins have been found to contain aluminum as well.

http://www.doctoryourself.com/alzheimer.html

A single aluminum coffee-pot was shown to have invisibly added over 1600 mcg aluminum per liter of water. This is 3,200% over the World Health Organizations set goal of 50 mcg per liter. Aluminum is known to build up in the bodily tissues of persons with Alzheimers disease, Parkinsons disease, and amyotrophic lateral sclerosis. Aluminum is a known neurotoxin. Aluminum is also a component of so- called silver amalgam dental fillings. Composite (white) fillings do not contain aluminum (or mercury, for that matter.) Most baking powder contains aluminum. Rumford brand baking powder does not, however. Neither does baking soda, which is a different substance entirely.

FACT: More than half of nursing home beds are occupied by AD [Alzheimers Disease] patients.

FACT: Alzheimers disease is the Number 4 Killer of Americans, causing over 100,000 deaths each year in the USA alone.


On January 15, 2006 at 11:04 AM, TruthFinder (guest) said...
Subject: Teflon Toxicity
http://www.ecomall.com/greenshopping/teflon4.htm

In new tests conducted by a university food safety professor, a generic non-stick frying pan preheated on a conventional, electric stovetop burner reached 736°F in three minutes and 20 seconds, with temperatures still rising when the tests were terminated. A Teflon pan reached 721°F in just five minutes under the same test conditions (See Figure 1), as measured by a commercially available infrared thermometer. DuPont studies show that the Teflon offgases toxic particulates at 446°F. At 680°F Teflon pans release at least six toxic gases, including two carcinogens, two global pollutants, and MFA, a chemical lethal to humans at low doses. At temperatures that DuPont scientists claim are reached on stovetop drip pans (1000°F), non-stick coatings break down to a chemical warfare agent known as PFIB, and a chemical analog of the WWII nerve gas phosgene.

http://ww3.komotv.com/Global/story.asp?S=3615478

A $5 billion class-action lawsuit is being filed against DuPont for failing to warn consumers of the dangers of an ingredient allegedly contained in Teflon, lawyers said Tuesday.

Two Florida law firms told the Associated Press they were filing the federal suit on behalf of 14 people in eight states who bought cookware coated with non-stick Teflon. It reportedly is made with a chemical called perfluorooctanoic acid (PFOA), which earlier this month the U.S. Environmental Protection agency said is "likely" to cause cancer in people, the AP said.

The plaintiffs contend DuPont has known for more than 20 years that the product caused cancer in lab animals, according to the AP. A company spokesman said federal tests "show that nonstick coatings used for cookware sold under the Teflon brand, do not contain any PFOA." Spokesman Cliff Webb added that DuPont would "vigorously defend itself against the allegations."


On January 24, 2006 at 12:56 PM, guest (guest) said...
Subject: surgical grade stainless steel cookware vs. Calphalon
I went to a "dinner party" that was really a sales pitch by a company called Saladmaster that makes surgical grade stainless steel waterless cooking pots and pans. The sales rep maintained that 1) this type of steel was purer than the standard 18/10 found in cheaper pots and thus wouldn't leach any nickel into your food and 2) that metals leach into your food from our Calphalon pots. To prove this later assertion, he boiled water with a teaspon of baking soda in both pots. The water from his pots tasted like water with baking soda but the water from the Calphalon had a horrible metallic taste. Based almost solely on this test our neighbor bought a set which STARTS at $3,000.

So, does nikel leach into your food from cheaper stainless steel pans and does aluminum leach in from Calphalon? Why did the water taste so much worse out of the Calphalon and what can it mean other than that we tasted the metals from the Calphalon pot?


On January 29, 2006 at 11:30 PM, TruthFinder (guest) said...
Subject: Teflon Toxicity
http://www.latimes.com/news/opinion/editorials/la-ed-teflon28jan28,0,1542186.story?coll=la-news-comment-editorials

EDITORIALS: THE SATURDAY PAGE THE EPA FOLLIES
Sticking up for health
WHEN IT COMES TO TEFLON, the Environmental Protection Agency is living up to its name. By calling this week for the reduction and eventual elimination of a potentially dangerous chemical used to make Teflon, the agency has shown it is willing to protect global wildlife and human health.

Unlike Teflon presidents or Teflon sports figures, Teflon itself has sticky health issues that refuse to slide away. A troubling compound used to make the slick stuff, called PFOA, is found in 95% of Americans and has been detected around the world, even finding its way into polar bears in Greenland, Alaska and Canada.

It's not clear how this chemical finds its way into the environment; it's removed from Teflon and other products during the manufacturing process. But PFOA is practically ubiquitous, used to make waterproof clothing, phone cables, building materials and more. In animal tests, it has been found to cause birth defects and has been linked to cancer and immune suppression, among other health problems. It stays in the human body for years and is passed on to a fetus during pregnancy.

Last year, the EPA went aggressively after DuPont Co., saying the chemical powerhouse that pioneered the use of PFOA had been hiding the substance's health risks for close to 25 years and had failed to report that PFOA had seeped into residential water supplies in Ohio and West Virginia. DuPont agreed last month to pay the largest administrative fine in the EPA's history: $16.5 million.

It would take years for the federal agency to ban PFOA; instead, in a rare move for the EPA under any administration, it called for preventing its release into the environment. Releases would be cut by 95% by 2010 and eliminated by 2015, it appears the eight major companies that use the chemical are agreeing to go along.

Before anyone slaps a halo on the EPA's head, it's worth noting that the agency is comfortably following a parade that was headed in this direction. DuPont has agreed to pay a settlement of up to $342 million in the water-contamination case — incentive enough to control its release. The company reports that it already has cut emissions of PFOA over the last few years by 94%.

Still, EPA officials made the right move. It's good to see the agency back in action; here's hoping it lasts.


On February 13, 2006 at 07:54 PM, baula (guest) said...
Subject: Costco Kirkland Signature Stainless Set w/Bonded Copper Base
Yesterday at Costco I saw the following 13-pc set:

http://www.costco.com/Browse/Product.aspx?Prodid=10048379&whse=BC&top...s=1

I might prefer the tempered glass lids over stainless to view the cooking action, but my web research hasn't unearthed anything close in either 13-pc sets or copper bonding to this set @ 199.99. Closest ones are Emeril or Cuisinart on Amazon, both of which have less or zero copper and fewer pieces for the same price. No idea of the precise thickness on the stainless-alu-copper-alu-stainless layers, but I can guess no less than industry standard from the physical heft of in-store demo pieces and general online discussions.

Does anyone here have experience or an opinion on the value and quality of this as a jack-of-all trades starter set? I've generally had very good results with Kirkland private label products, save the reduced prestige from the brands they compete with head-to-head, but I could care less about the brand if the goods are legit and cost 50% less than the equivalent.

Thanks in advance for any thoughts.


On February 26, 2006 at 03:09 PM, guest (guest) said...
Subject: teflon scare
Regarding the health concerns about teflon, I can personally attest to its byproduct fumes being toxic as it nearly killed my African Grey parrot. I was heating a pot of water, got distracted and the water evaporated which caused the teflon coating to get hot. I myself noticed my throat feeling acrid, but the poor bird was puffed up, breathing with great difficulty and listing. He was so ill, he didn't mind me putting my hands around him to place him in his carrier for an emergency trip to the vet. My dear parrot survived, and fortunately being an engineer I could afford the three days of vet services that totaled over $700. After that incident, all teflon coated cookware and ustensils were tossed out. I have a gas stove, so cast iron, pyrex, stoneware and enamel (graniteware) cookware along with wooden and stainless utensils are used without adverse effects. Oh, just for the record, the parrot is definitely a 'boy', I had him sexed via blood analysis when I first got him. Engineers like to know everything! I'm like the fourth or fifth owner but he's a lot of fun. If anyone is interested about parrot itelligence, google Dr. Irene Pepperberg who has an African Grey named Alex. Trust me, Greys are very smart, so please if your going to have birds as household pets, then get rid of your teflon cookware and utensils. All it takes is one careless moment and your feathered companion might not be so lucky to survive fumes from overheated teflon.


On March 05, 2006 at 06:57 AM, donandmel2 (guest) said...
Subject: Teflon vs. Anodized Aluminum
So, is there a difference between "Anodized Aluminum" and "Teflon?" Is Anodized Aluminum subject to the same health risks as Teflon?
Mel


On March 05, 2006 at 08:26 AM, Michael Chu said...
Subject: Re: Teflon vs. Anodized Aluminum
donandmel2 wrote:
So, is there a difference between "Anodized Aluminum" and "Teflon?" Is Anodized Aluminum subject to the same health risks as Teflon?

Anodized aluminum and teflon are two different things.

Anodized Aluminum is a type of aluminum that has been treated to provide an thin but extremely hard aluminum hydrate layer. This layer is non-reactive, so it does not have the downsides of plain aluminum (which may react with acidic foods changing their color and taste). When cooking, treat anodized aluminum pans as if it were a (black) stainless steel clad aluminum pan. It is possible to put a nonstick layer (such as Teflon) onto an anodized aluminum pan, but I don't really see the point - you'd be covering up the ultra-hard layer that was put on.

Think of Teflon as the clear coat of your car's paint job. It makes the surface nice and smooth and slippery so it's easy to clean off. They can put a coating of Teflon onto basically any cookware material that you can scuff up in manufacturing - stainless steel, aluminum, and sometimes even titanium (for lightweight camping).

Calphalon has a newer line of pans that they call infused anodized aluminum that is supposedly nonstick without the use of Teflon. For some, it seems to work magically well - sticking to produce fond when they want it to and releasing at just the right time. For others, it's just a pain to work with. Your milage may vary.

So far, my favorite non-stick (Teflon) pans are made by Scanpan. (I use this 9-1/2 in. fry pan whenever I make eggs and other "sticky" foods. I use stainless clad aluminum for just about everything else.)


On April 05, 2006 at 03:51 PM, rosemarygrace (guest) said...
Subject: cookware...Lifetime
I loved the article.

Do you have an opinion on "waterless" cookware. Kuhn Rikon and Lifetime carry this stuff. It is VERY expensive, but if you ever sat through a Lifetime Song and Dance at a home show, you would think you are actually killing your family if you don't buy this stuff.

Please advise if you or anyone out there is familiar with this stuff.

Thanks much.


On April 21, 2006 at 06:34 PM, nurmich (guest) said...
Subject: waterless cookware
I have the Saladmaster stuff that was handed down to me and am just learning to cook the right way on it. I think it's great! I'll say my grandmother who is 91 is as clear-headed as anyone I know is the one who handed my set down to me. I believe that the aluminum in the pans really does cause problems. It's just that it takes a lifetime to show up and so the lab tests don't show it. By the way they do have to take Teflon off the market by 2015, so the tests have shown something. I'm sold on the waterless cookware--except I haven't figured out how to scramble eggs without the non-stick coating yet. Any advice?


On June 06, 2006 at 07:27 PM, cook in CA (guest) said...
Subject: teflon and induction burners
Hi there,
Can someone explain to me--in lay terms (I didn't do so well in science in school!)--why teflon pans don't heat up on induction burners? Everytime I put a teflon pan on an induction burner, the burner turns off. It's a great mystery to me!


On June 06, 2006 at 07:39 PM, Michael Chu said...
Subject: Re: teflon and induction burners
cook in CA wrote:
Hi there,
Can someone explain to me--in lay terms (I didn't do so well in science in school!)--why teflon pans don't heat up on induction burners? Everytime I put a teflon pan on an induction burner, the burner turns off. It's a great mystery to me!

Your teflon pan is most likely made out of aluminum. Induction cooktops work only on cookware that is affected by a magenetic field. An easy test to see if you cookware will work on an induction cooktop is to take a magnet (like a refrigerator magnet) and see if it will stick to the bottom. High quality stainless steel clad aluminum (such as All-Clad but not Farberware or Calphalon's new line of cladware) and cast iron are your most likely candidates.


On July 01, 2006 at 03:03 AM, an anonymous reader said...
Subject: Cooking with Saladmaster
For the eggs, the key is keeping the heat around medium and making sure the pan is warm before you put the eggs in (drop in a drop of water and if the water rolls around its hot). You can cook without adding anything to the pan, but if you want to make it easier, a little bit of butter makes the pan totally nonstick. We have had Saladmaster for a few months and would highly recommend it to anyone looking to try and eat healthier. It is very high quality cookware and will last a lifetime. However, if you aren't going to buy into the lower heat waterless concept (which preserves vitamins and minerals) you are simply buying good cookware. The idea is to actually buy into the concept of how to cook for better health.


On July 03, 2006 at 06:09 AM, GaryProtein said...
Subject: Re: Aluminum Toxicity
slightly off-topic, I'm guilty of continuing it, but I didn't initiate it here . . . .

TruthFinder wrote:
on Jan 6, 2006--Aluminum toxicity is a recognized medical condition.
. . . .. Aluminum is also a component of so- called silver amalgam dental fillings. Composite (white) fillings do not contain aluminum (or mercury, for that matter.) . . . .


Well, what can I say. I am a Prosthodontist. I am an anal, and ultra-compulsive dental bioengineer. A Prosthodontist is a dental specialist who has spent three years in an accredited program after four years of dental school studying the restoration and replacement of teeth, the construction of fixed and removable tooth and implant supported prostheses, cosmetic dentistry, and is an expert in dental biomaterials. The earliest silver amalgam was made in the early 1800's, but the most similar predecessor of modern silver amalgam was invented in 1895 by GV Black--and this was the basis for all modern amalgams. The most modern/currently used silver amalgams, produced by numerous manufacturers (let's say after the mid 1970's) is a eutectic alloy of silver, tin, copper, palladium, indium and mercury. A eutectic alloy is a mixture of substances in fixed proportions that melts and solidifies at a single temperature that is lower than the melting points of the separate constituents, or of any other mixture of them. To my very best knowledge, THERE HAS NEVER BEEN ANY ALUMINUM IN ANY DENTAL/SILVER AMALGAM. If however you have real information, such as a product insert (always supplied) which contains the exact ingredients accompanying the specific brand of amalgam you are referring to, NOT something cut and pasted from some ridiculous website, then I am interested in the reference. If not, what I say here is the total fact on that matter. Can you tell this is a sore point with me?

Next, while resin composite fillings (tooth colored composites) do not have mercury which many people are so unnecessarily concerned about especially since the advent of high copper and palladium containing alloys in the mid 1970's, let me be the first to inform the wholistic lovers of composites that the epoxide resin component of the composite contains compounds very similar to/congeners of estrogens. About 10-15 years ago this was brought to light, but no one wanted to hear this because everyone wanted tooth colored fillings. SO . . . all you people who want really fine dentistry, you have two main choices--gold or porcelain. The finest material to use in small cavities would be compacted gold foil, followed by cast gold inlays for most situations and then gold or porcelain fused to gold crowns, which are the benchmark ("gold standard") by which all other materials are judged. While porcelain and other ceramic tooth colored materials look natural, they tend to wear down the opposing teeth faster than another tooth or gold chewing against it. Furthermore, all-ceramic/non-metallic restorations generally need to be cemented/"bonded" by a resin composite cement or else they break. So, you can't totally avoid the composite here either, and it doesn't seem to be a problem either, although you can minimize it's surface exposure by using the material as a cement, rather than the bulk restorative material. Now that you know that nothing is perfect, you can sit down and try to decide where the real dangers (if any) really are and what you would like in your own mouth. You will get more mercury from eating large fish--at the top of the food chain, because heavy metals tend to be cumulative in tissues--than from silver amalgam fillings.

I'm sorry about the tirade, but there is so much bad information out there that I am bombarded with on a daily basis that I had to set this part straight, hopefully falling on intelligent ears.

As far as the "purity" of the special cookware mentioned by a guest on Jan 24. 2006, that is "purer" than 18/10 in cheaper pots and pans that a guest poster was concerned would leach nickel, let me say that cookware and flatware comes in 18/8, 18/10 and rarely 18/12--the best. The first number is the amount of chromium that is contained in the stainless, i.e., 18 is 18% chromium. The second number is the amount of nickel, i.e., 8 stands for 8% nickel. So 18/8 means that this stainless steel contains 18% chromium and 8% nickel. 18/10 is 18% chromium and 10% nickel. The higher the numbers the more corrosion resistant the material. 18/0 is a misleading designation. Both 18/8 and 18/10 contain nickel and are part of the grade family "300 series" stainless. 18/0 means that there is 18% chromium but zero nickel. When there is no nickel the stainless grade family is the "400 series". 400 series are not as corrosion resistant as the 300 series and are magnetic, where the 300 series are non-magnetic. Therefore the more expensive/better/shinier stainless steel alloys have MORE nickel. Those alloys with more nickel are more corrosion resistant and have a brighter shine/luster. Regarding the term "purity", if the cookware the guy was selling was 100.000% pure lead, it would be very pure, but I wouldn't want to eat from it. Using the word "purity" is VERY misleading.

Regarding Micheal Chu's comments on June 7, 2006 on induction cookware, as he stated, the cookware must be affected by magnetic fields to heat up. Therefore, they (the All-Clad and others) must be 400 series stainless steels OR be 300 series and have a different magnetically inductive meterial in the base of their cookware. Maybe that information is a proprietary secret. It's a pity you can't use tinned copper--generally recognized as the best cookware on an induction stovetop.

The aluminum in cookware is another discussion, and I don't want to get into here, but I will say aluminum as a cause of Alzheimer's Disease is very controversial and definitely NOT proven. Some researchers believe the aluminum is a CAUSE, while others feel the accumulation of aluminum is the RESULT of the disease. Since we are on the topic of metals and Alzheimer's, zinc is another metal being looked at as a cause. Try doing some research in the National Library of Medicine and the National Institutes of Health. The verdict is definitely NOT IN on aluminum, in fact there are many other suspected causes which have more evidence than aluminum.

Since concern about aluminum in antacids was mentioned in another post, here is a list of aluminum containing antacids:

Di-Gel liquid
Gaviscon tablets
Gelusil liquid
Gelusil tablets
Extra strength Maalox
Mylanta & Mylanta Double Strength liquid & tablets
Tempo Soft Antacid

These antacids are Aluminum-free antacids:

Alka-Seltzer
Alka-Mints
Di-Gel tablets
Maalox caplets
Mylanta gelcaps
Rolaids tablets
Titralac
Tums E-X


Thank you, and have a nice day! :)


On July 21, 2006 at 07:12 AM, GaryProtein said...
Subject: Re: waterless cookware
nurmich wrote:
. . . . . By the way they do have to take Teflon off the market by 2015, so the tests have shown something. I'm sold on the waterless cookware--except I haven't figured out how to scramble eggs without the non-stick coating yet. Any advice?


The statement by nurmich (April 21, 2006) is not correct. Teflon will be here.

Teflon PTFE and e-PTFE ---- expanded PTFE (Gore-Tex) saves lives. The cooking counterpart is OK too. e-PTFE (Gore-Tex) is used in surgery in several medical fields. There are many different configurations of Gore-Tex used in surgery. Google it. It is notably used in cardiovascular surgery for heart and great vessel grafts and repairs and in oral surgery bone grafting procedures. What is to be eliminated is the Perfluorooctanoic Acid (PFOA) from factory emissions and finished products by 2015.

http://www.epa.gov/oppt/pfoa/

http://www.epa.gov/opptintr/pfoa/pubs/pfoastewardship.htm

http://www.epa.gov/opptintr/pfoa/pubs/pfoarisk.htm


If you don't like Teflon, you can always use SwissDiamond non-stick cookware. It is not a teflon product. It is VERY good but fairly expensive. I like it a lot.


On July 29, 2006 at 09:04 AM, an anonymous reader said...
Subject: Cooking with Gas
I thoroughly enjoyed the article and all the comments, however I haven't seen any address the appropriateness of the heat source to the cooking material. We have natural gas and some of the clad cookware is separating. (We're using Macy's Tools of the Trade Grand Prix, about 20-25 years old) For replacing it, I've seen some cookware with maximum temperatures posted, yet the fire itself is hot, even at low temps. Granted, I don't expect to be cooking for another 25 years, but I don't want to keep buying cookware either. From the post's I've decided stainless clad aluminum or anodized would be best, but how would the temp or gas affect the wear?


On September 12, 2006 at 03:50 PM, Helen Wills (guest) said...
Subject: Teflon ??
My Husband just purchased - Pyrex Non-Stick Cookie sheets.
I do not want to use ' Teflon ' - nor is the word used anywhere on the labeling.
Iwould like to know what is used on these sheets and why the Canadian Government allows the product to be sold without clear definition.
Can anyone provide knowledge on this substance?

Thanks :angry:


On September 16, 2006 at 03:20 PM, dg (guest) said...
Subject: cuisnart/all clad comparison
I am searching for a comparison of performance between the all clad line and the cuisnart tri-ply 18/10 stainless cookware. It appears on initial comparison that the construction is essentially the same. The all clad is significantly more expensive, however, making me wonder what the inherent differences may be in specifications and performance. Can anyone provide comparative feedback?


On September 28, 2006 at 07:07 AM, danemodsandy said...
Subject: Re: cuisnart/all clad comparison
dg wrote:
I am searching for a comparison of performance between the all clad line and the cuisnart tri-ply 18/10 stainless cookware. It appears on initial comparison that the construction is essentially the same. The all clad is significantly more expensive, however, making me wonder what the inherent differences may be in specifications and performance. Can anyone provide comparative feedback?


Hi:

There might be some minor difference in performance that could be detected if Julia Child rose from the dead and cooked with them side-by-side, but there is not that much difference in most quality tri-ply cookware. Where there IS a difference is in Cuisinart's approach to marketing. They often change the design and specs of their cookware to update the fashion appeal of their lines, and when they do, you're not able to get the former version for very long. This makes a warranty less meaningful than most of us would like it to be. Let's say that five years from now, you have trouble with a Cuisinart skillet. You got a "limited lifetime warranty" with it, so you're fine, right? Well, maybe not, because if Cuisinart has discontinued your cookware in favour of something else that has become fashionable, there may be no replacement stock with which to honour your warranty claim. You'll get an offer to replace with a "comparable" piece, or you'll get some other offer. What you won't get is a new piece just like the old one. Cuisinarts is in the process of phasing out its "Everyday" cookware, the classic copper-stainless sandwich construction, probably due to the rising cost of copper. All Cuisinart lines now feature aluminium in the sandwich. If you valued the copper sandwich enough to pay well for it, would you be happy with an aluminium-sandwich piece to replace it under warranty?

All-Clad is also not a very consumer-friendly company, from what I've heard from friends still in the biz (I was in the kitchenwares business for six years), and the stuff costs what a mortgage payment used to. If you would like to save a lot of money over the price of All-Clad, and get essentially the same quality and performance, I would suggest you take a look at Tramontina's Tri-Ply line. It's so close to All-Clad you can hardly tell the difference in some pieces. Tramontina is a Brazilian company that now makes cookware in the United States (they bought the old Mirro plant in Manitowoc, WI for the purpose- nice to see a foreign company bring jobs HERE for a change, eh?), and in China.

If you want to see some Tramontina Tri-Ply, with pricing, go to: http://www.kitchenfantasy.com/shopping_cart/sspots.html You should be aware that Tramontina, like a lot of other companies, makes several lines of cookware, with Tri-Ply being their highest quality. Be absolutely certain that any Tramontina you buy is Tri-Ply, not one of their lesser lines like Sterling. Be especially careful on eBay; some ignorant sellers (I'm giving them the benefit of the doubt here) describe all Tramontina as tr-ply, because of the three-layer sandwich on the bottom of the cheaper lines. ONLY the Tri-Ply line has the same straight-gauge construction as All-Clad, with a layer of aluminium between two layers of stainless, that goes all the way up the sides of every piece.

Good luck!


On October 12, 2006 at 02:51 PM, paulr (guest) said...
Subject: A couple of things to keep in mind
Remember that different kinds of cooking require different characteristics. There's no one perfect material.

For sauteeing and especially for delicate sauces that require control, nothing is better than copper, for its fast response.

But fast response is a problem for other things. If you want to deeply brown or blacken a large piece of meat, you want heat retention. The best material is probably heavy cast iron, with its high density and high specific heat. The pan will maintain high temperatures even after the room temperature food is thrown onto it. Heavy, slow response materials like enameled cast iron also work especially well for slow simmering (I don't fully understand the physics behind this, but a couple of big batches of stew or soup in a dutch oven will sell you on these qualities).

A minor issue with copper is its poor ability to keep food warm. That fast response means your sauce will cool rapidly as soon as the fire goes out. If you use copper sauce pans (lucky you if you do) it's worthwhile to adopt professional techniques like a bain marie (water bath) to hold the food at temperature, if you can't serve immediately.

Heavy aluminum cookware comes somewhere in the middle and is a good general purpose solution.

Surface material is also worth strong consideration. Like most cooks, I'm starting to prefer stainless steel interiors for most pans. It does almost everything well, and its bright color makes it easy to judge the state of carmelization (technically the Maillard reaction) of pan juices. Very important in any kind of sauteeing and roasting. Clad metal comes to the resucue: 18-10 stainless lined copper or aluminum.

I like my anodized aluminum pans, too, but the surface is definitely harder to use, and ultimately doesn't hold up as well.

If you cook a lot of eggs, you should have at least one non-stick pan. Get a cheap one. They don't stay nonstick very long. Even the ones warranted forever are only warranted to keep the surface intact ... they say nothing about how well it will actually work.

Naturally nonstick surfaces like seasoned spun steel or cast iron work great for things like fish, but beware of using for omlettes ... your breakfast will taste like fish, fried dumplings, or whatever else you cooked in there last night.

If you choose clad or laminated aluminum, keep in mind that pans vary greatly in overall thickness and thermal mass. Pans that look the same will have very different cooking characteristics. There isn't always a right answer as to what's better ... what you cook, how you cook, and what you're used to will play into this. Best to borrow some pans before investing.

And don't buy a set. False economy. Get what you need, in the material you need, one at a time.


On October 12, 2006 at 03:12 PM, paulr (guest) said...
Subject: one more thing about copper
You won't really get the benefits of copper from cheap copper cookware (pans with thin disks of copper on the bottom, clad pans with a thin layer like the all-clad line, or the french "tourist copper" pans with 1.6 mm thickness and brass handles.

Some of these pans may be decent, but if you want the benefits of professional copper cookware, you need the real deal: 2.5+ mm thickness, usually clad with 18-10 stainless, almost always with a cast iron or stainless steel handle.

The more traditional pans are tin-lined. These offer some advantages (slightly faster response, and they are re-tinable) but many disadvantages (fragile surface, and low melting point of tin makes many kinds of cooking impossible).

The brands I can vouch for are Mauvielle, Bourgeat, and Falk.

Copper prices are ridiculously high right now.


On October 15, 2006 at 12:04 AM, Neoserenity (guest) said...
Subject: Best pot for stews & soups?
Hi all,

I was wondering if you could recommend a safe but low maintenance pot (~ 10 quarts) for making beef stews, soups, and other slow-cooking foods?

Your advice is greatly appreciated (I've been pulling my hair out trying to decide)!


On October 15, 2006 at 04:14 PM, GaryProtein said...
If 8.5 quarts is enough, I recommend SwissDiamond. I love my SwissDiamond stock pot. Their non-stick surface can be used to brown meats in the pot prior to the remainder of the cooking as a stew, it is a durable non-stick and nothing cleans up easier. By the way, for the teflon haters, the non-stick is NOT teflon.


On October 27, 2006 at 03:09 AM, juliet (guest) said...
Subject: waterless cookware
I have been researching cookware for weeks, and I can't seem to make a decision. My mom has waterless cookware from Health Craft and loves it. However, I do not want to pay the high price. I keep finding other waterless cookware sets that are a lot cheaper. Two are Vapo-Seal and Maxam's World's Finest 17 pc. set (KT17ULTRA). Does anyone know anything about these? Are there any waterless cookware sets with stainless steel handles at a reasonable price (most seem to have the phenolic handles)? I love the looks of All-Clad, but I don't think it is stackable like other waterless cookware sets. I would also prefer not to pay that much. Any suggestions?


On November 17, 2006 at 04:21 AM, Marco (guest) said...
Subject: Waterless Cookware
Maxam has a great set of waterless cookware. To be honest there are alot of waterless cookware out there, REMEMBER one thing you need at least a 5 ply to cook waterless. Store sets are 3 ply and dont work as well.
I have cooked waterless on 18/10 and t304 and t316L its all about cooking on low heat and haveing atlest a 5 ply cookware.


On November 17, 2006 at 11:18 PM, GaryProtein said...
What exactly is waterless cooking and why do you need 5 plys?


On November 25, 2006 at 03:44 PM, chiantra (guest) said...
Subject: waterless cookware
just wondering how those maxam waterless 18/10 stainless steel cookware are, in quality? Has anyone tried them? I know they are supposed to be healthier to use but I've also been looking at buying a set of Cuisinart Multiclad Pro.


On December 03, 2006 at 06:45 AM, Elgog (guest) said...
Subject: Cusinart Chefs Classic cookware
I use the Cusinart Chef's Classic cookware and like it a lot. It is 18/10 stainless with the 4mm aluminum disk in the bottom. The warrantee is void if you cook with high temps. I assume it's because of the material they use to bond the disk to the botom of the pan. Probably some high temp epoxy or something. In any case, these pans are reasonably priced and work well. I do have several non-stick Farberware egg pans for eggs and other sticky stuff.

The thing I don't like most about teflon is that if you cook at high temps with teflon, it loses it's non stick properties. For instance, if you cook bacon in a teflon pan, over a very short period of time, that pan will loose its non-stick properties. Teflon is not a long term solution for cook ware. As for multi-clad cook ware, I was a chef for many years and cooked on pans that heated from the bottom. I am not sure I want a pan where the sides are as hot as the bottom. I need places in the pan that are cooler so I can bring the food to the heat and when its done, rotate it up to the top and bring more food to the heat. I could have bought another brand of multi-clad cookware that was significanlty less expensive, but I wanted cookware that I was used to cooking on. My 17 piece set cost $249 at Chef's Catalog. If I would have purchased them separately it would have cost more than $700. So I defeinitly recommend buying a set rather than one at a time. Also, make sure the set has what you need. The All Clad set, 9 pieces for $800, has a 3 1/2 qt saute pan. This is a very small pan. Also, things like a vegatable steamer insert typiclly get very little use unlike, say, a pasta cooking insert. I would also not get a copper set because copper is so soft that the pan dents and will not make contact with electric cooking surfaces.

A friend of mine has a Calfalon anodized aluminum set and he has sent several pans back for warrantee coverage because that pans failed over time. I don't want to be shipping cookware every few months.

Finally, I bought a set of Calfalon cookware (about $3000 worth) and took it back because everthing I cooked in it stuck to it. I could not get some of it off when I retuned the set. Also the care instructions for the Calfalon are draconian. Apparently normal use of this cookeware leads to performance failures.

In summary, the Cusinart Chef's Proffesional cookware performs very well, cleans well. You can use oven cleaner on it if you have a major burn, unlike aluminum. I have had trouble with Calfalon as well as some of my friends and I don't think I would like the multi-clad cookware because it changes the way I am used to cooking.

Thanks for listening.


On December 03, 2006 at 06:00 PM, GaryProtein said...
Subject: Re: Cusinart Chefs Classic cookware
Elgog wrote:

The thing I don't like most about teflon is that if you cook at high temps with teflon, it loses it's non stick properties. For instance, if you cook bacon in a teflon pan, over a very short period of time, that pan will loose its non-stick properties. Teflon is not a long term solution for cook ware. A friend of mine has a Calfalon anodized aluminum set and he has sent several pans back for warrantee coverage because that pans failed over time. I don't want to be shipping cookware every few months.

Finally, I bought a set of Calfalon cookware (about $3000 worth) and took it back because everthing I cooked in it stuck to it. I could not get some of it off when I retuned the set. Also the care instructions for the Calfalon are draconian. Apparently normal use of this cookeware leads to performance failures.


I have always felt (and you can see other posts of mine here) that Calphalon is a well advertized, high priced, low quality rip-off.

The likely reason you have had sticking with teflon is because you probably have "seasoned" the grease on it which is preventing the teflon from acting as a releasing agent. There might be other reasons, but try really cleaning the pot VERY well and see if the problem goes away.


On December 11, 2006 at 01:08 PM, an anonymous reader said...
Subject: Materials
Hi Michael,

I was wondering if you know the exact material used for wok pans. I know that there are many variations for its manufacture, but do you know what exact type of cast iron? or carbon steel, or aluminium?
thanks

Mish


On December 11, 2006 at 05:43 PM, Michael Chu said...
Subject: Re: Materials
Anonymous wrote:
I was wondering if you know the exact material used for wok pans. I know that there are many variations for its manufacture, but do you know what exact type of cast iron? or carbon steel, or aluminium?

Traditional Chinese woks are made of thin cast iron. As to the type of cast iron, I don't know - most likely some form of grey cast iron. You can give The Wok Shop a call or send them a message asking if they knwo the specific type of material used in their cast iron woks. Also, during the last several decades, carbon steel has become more popular as a material for woks both in China and in the U.S. The specific type of cast iron or carbon steel is dependant on the manufacturer.


On December 12, 2006 at 01:03 AM, an anonymous reader said...
thanks for your help


On December 28, 2006 at 12:33 AM, Matt and Anna said...
Subject: Zinc Coated Fish Kettle
Hi, great site.

We have a large fish kettle that has a generous coating of what appears to be zinc inside and out. We used it for the first time last night over our stove's gas burner to poach a trout. The poaching water had stock, wine and onions, and the resulting poached sea trout was delicious. We boiled down the poaching water ain the kettle to a seriously good-smelling stock.

On emptying the stock the next morning we were horrified to find that the zinc lining on the inside had been melted away above the burner jets and there were small blobs of zinc loose in the bottom of the kettle.

We ditched the stock. We don't appear to have any of the usual symptoms of zinc poisoning.

I have been trying to reproduce the melting effect this morning. Over an hour or two of boiling, there is no melting but there seem to be some new small loose blobs of zinc (qty 3 @ 1mmx2mm) forming again, indicating a dissolution/precipitation process. Why would this be happening? Why wouldn't any zinc in solution plate back out onto a cooler part of the vessel wall? Isn't zinc a safe coating for cooking vessels?

A Canadian government food health site warns against cooking or storing in zinc any foods or liquids with a pH below 4.5. I suppose its possible that the poaching water was made acid by its constituents, and more so by the reduction, but we have no means of measuring pH.

Our water comes from a series of rainwater tanks - a main concrete tank with some other plastic and galvanised tanks. We also have a galvanised roof and tend to have leaf litter in the gutters. I imagine that the leaf litter may acidify the water, but the concrete tank walls should neutralise that.

Do we need to be concerned about zinc migrating off the kettle into the fish? At what point would the vessel stop dissolving zinc into the hot water? Would this happen with perfectly neutral water?

Thanks,

Matt and Anna


On February 20, 2007 at 10:46 PM, Something Fishy? (guest) said...
Subject: eGullet Link
I love this site, but isn't this article awfully derrivative of the eGullet article Shalmanese linked to back in 2005? Given that the eGullet article predates this one by some two years, and given the extreme similarities in structure, data and information presented, this seems to be just a shorter rewrite of the eGullet article. That's all well and good, but shouldn't credit be given where it's due?


On February 21, 2007 at 04:42 AM, GaryProtein said...
Subject: Re: eGullet Link
Something Fishy? wrote:
I love this site, but isn't this article awfully derrivative of the eGullet article Shalmanese linked to back in 2005? Given that the eGullet article predates this one by some two years, and given the extreme similarities in structure, data and information presented, this seems to be just a shorter rewrite of the eGullet article. That's all well and good, but shouldn't credit be given where it's due?


If you look at any blog site in any topic, everything has been discussed before someplace, but times change, technology moves on, different people have more varied viewpoints, and sometimes the answers to questions change as more data becomes available. In some topics, we have links to other references, giving them credit where it is due. So, in view of the fact that we are not plagiarizing other blogs, no credit is due anyone, as we all have original writings on the topics we discuss.


On February 28, 2007 at 04:55 AM, Mista Rajaz (guest) said...
Subject: I prefer copper
because of its high therman diffusivity thickness which distributes the heat evenly and it is also very resonsive


On March 16, 2007 at 02:47 PM, an anonymous reader said...
Subject: A couple things i have found out
Now here, i disagree with your results. I'm different, making me instantly cool, dangerous, rebellious, forward thinking, creative, and stupid at the same time. I think aluminum is the better cooking material. Aluminum looks better, and it's cheaper. But what I've discovered, using the thermal response is that while copper pans may be able to respond 20% better, Aluminum pans can get the same heat distribution, 68% lighter. I took the diffusion numbers and plugged them into the relative weight of copper and aluminum. To get the pot diffusing on the same level, you still only need 32% of the weight. That's 68% lighter, if you don't care about weight it can be used to make the pot 136% thicker. And 136% thicker seems more important then 20% faster heat response to me.

Tell me if i horribly screwed up somewhere, because these numbers seem a little one sided to me.


On March 16, 2007 at 03:07 PM, an anonymous reader said...
Subject: Re: A couple of things to keep in mind
paulr wrote:

For sauteeing... ...nothing is better than copper, for its fast response.

Really? I don't have a saute pan, but i assumed aluminum was better, since it's significantly lighter. So is copper so much better that the huge weight is worth it?


On August 06, 2007 at 04:05 AM, PASSBY (guest) said...
Subject: about wok
Most woks that are made in China are cast iron. There are wrought iron and pig iron. Pig iron is regarded to be suitable for slow stew and braised. suitable for old people and long last. wrought iron is suitable for quick stir fry, and for young people.


On October 25, 2007 at 01:02 PM, bird lover (guest) said...
Subject: thank you
Thank you so much for the comments on the Teflon and dangers to our caged feathered friends. Reading all the other advise and comments were beginning to scare me that no one knew about this deadly hazarded.
I also want to thank the Prosthodontist for his informative comments. I still prefer to not take any chances with aluminum since any future test results won't do me any good after the fact. I don't find the use of aluminum any thing I will miss. My original question was to find out rather Nordicware was made with Teflon. It appears it is and so I search for a grill to put on top of the stove that doesn't have such things on it.
Does one exist?


On November 01, 2007 at 06:21 PM, Student (guest) said...
Subject: Thank you
Thank you for writing this article..it helps a lot for my research..Thanks one a again :)


On November 29, 2007 at 07:32 PM, sadie king (guest) said...
Subject: saladmaster
Has anyone heard of Saladmaster? It it a higher price point than the other mentions, but it is the only one that will not allow the unhealthy aluminum to react or leach into the food because of the 316L metal used on the inside. It is a full-body even heat and makes food taste better as well. Just wanted to through that out there since it wasn't mentioned in the metals of stainless steel. :)


On December 01, 2007 at 02:34 PM, cookie (guest) said...
Subject: cookware
I recently purchased a 12" saute pan by Gourmet Standard and I love it!! Before that, I had purchased a complete set plus extra pieces of Analon Titanium, which I had thought was the optimum cookware, jack of all trades. I was wrong. You need different types of cookware for different food. I was always a believer in the non-stick, being health conscience. But using it is counter-productive. Even though it is non-stick, you still need to add some oil. Since the pan is non-stick, the oil doesn't stick to the pan. When you swirl the pan to spread the oil, it just pools up. When you then add your food to the pan, it absorbs that puddle of oil, so much for low fat cooking. And that's all you are doing with nonstick pans is just adding heat to food, nothing to do with bring out flavors or caramelizing food or any techinque having to do with the craft of cooking. The conclusion I arrived at after cooking for 12 years (experimenting, researching, reading tons or cookbooks, and approaching a new recipe as nothing less than a project, I guess I am just a frustrated engineer), I discovered all I need is the Gourmet Standard 12" Tri-ply saute pan for cooking everything but eggs. For eggs, I find I need a nonstick skillet (fry pan). Right now I have the Analon Titanium non-stick, which works very well. The next one I will get will be the Gourmet Standard Tri-ply with nonstick coating. It is difficult to get anything to adhere to aluminum. The best adhesive for Al is C-8, which is toxic and the major players say they don't use is anymore, but tests have found traces of it in there cookware. But stainless steel doesn't have the same issues as Al, to their options open up for nonstick coatings and its adhesives, theoretically they should be able to produce a kick- a@# product, with superior nonstick capability that won't flake off. I also discoved that gourmet standard makes a tri-ply cookie sheet with non-stick coating. I just ordered it from amazon. hopefully it will live up to my expectations. the cookware is aluminum tri-ply. they are constructed and look just like all clad for 1/3 the price. the 12' saute was about $100. So far the best pan I have cooked in. Easy clean up to, because of the nickel coating. love it, highly recommend it!!!!!


On December 02, 2007 at 02:21 PM, Dilbert said...
cookie -

if you're willing to pay for good pans, take a look at the traditional copper styles - now available lined with stainless. I have some of the 3mm Bourgeat and they are superb.

thermal conductivity (BTU/(hr-ft-'F) of
aluminum = 136
copper = 231
silver (the highest) = 248
stainless (304) = 8


On February 02, 2008 at 07:53 PM, momuv3 (guest) said...
Subject: Gas ranges
I was hoping to find a cookware that works best with high heat such as gas flame. I just got a new gas range going from an electric and all of my pots and pans are non stick. A couple of them are Aluminum with a copper bottom. What I am finding is that the Aluminum gets hot around the sides of the pot because the flame is round. Burning food and staining the inner sides of my pans. The non stick scares me because it is not supposed to be exposed to such high heat. What works best with flame cooking? Also do you know of cast iron types that have heat qripping handles that don't burn your hands?


On February 02, 2008 at 08:32 PM, Auspicious said...
Subject: Re: Gas ranges
momuv3 wrote:
Also do you know of cast iron types that have heat qripping handles that don't burn your hands?


Fold a dish towel into a pad and hold the handle with that. Works great and still lets you shove the cast iron into the oven for finishing.


On February 02, 2008 at 09:22 PM, Dilbert said...
momuv -

>>What works best with flame cooking?

there's no one single absolute answer to the question.

much depends on how you cook and the extend of your own personal "demands"
huh? you said?

my dear mother does not know the meaning of "sear" and survived just fine for decades with her RevereWare
however if you tend to do high heat type stuff, you may find RevereWare lacking "technique support"

on the other hand, you can boil / steam green beans in anything.

I have a Farberware stainless pot with clad bottom that is de-laminating - severely - to the point it's headed for the trash.
so "clad" cookware is also not the end of all things.

non-stick:
yup - you've got a problem there. gas can overheat a non-stick pan to 400-500'F in very short order - and convert a non-stick to a super-stick in just a few seconds - and kill your pet bird just as quick.
that said, I use non-stick all the time on a larger diameter high BTU nat gas burner - do NOT go for the "preheat the pan" thing....
works fine for sauting mushrooms / high moisture content schufft you need in short order.

trying to fry an egg in a thin stainless - copper clad or other - over gas is an interesting exercise.
not recommended when cooking for company, but educational - and very much in tune for the times - instant graduation from that idea . . . .

cast iron - great stuff.
handles: I actually have one square frying pan with a screw in wooden handle.
one point of cast iron is cooktop-to-oven.
the high end 'other' brands do not have "plastic" knobs or handles that will stand up to high oven temps over time.
so, if you do cooktop-to-oven, get some potholders & trivets.

if you watch the cooking shows, it's most interesting to observe the background of real restaurants - seen now and then, depending on chef / show - real locations that prepare food - not film stages.
I can categorize two "real" scenes:
- a not high end place. run of the mill aluminum saute/fry pans - all warped and grungy.
- the higher end places - racks and racks of grungy copper pots/fryers/sautes/sauce pans hanging about.

a third scene is stuff like Julia Childs' home kitchen - walls of hanging copper pots & molds - all brightly shined. never used; decoration.

bottom line:
you need pots for boiling / steaming - glass, stainless, alum - take your pick.

you need cookware for slower evenly distributed heating - omelets to (non-burnt) sauces / stews.
thick bottomed alum / stainless / clad / copper

you need cookware for the sear at megamillion degrees followed by oven finishing: cast iron or copper.

how many of each, what sizes / shapes, will be a concerted compromise of what & how your personal preferences & habits extrapolate.


On February 03, 2008 at 02:09 AM, GaryProtein said...
Subject: Re: Gas ranges
momuv3 wrote:
. . . . What I am finding is that the Aluminum gets hot around the sides of the pot because the flame is round. Burning food and staining the inner sides of my pans. . . . .


What you have noticed about the burning of food on thew sides of pans is common on gas stoves because just about every one on the market has a ring shaped burner, which allows the flame to basically go around the sides of the pan without actually heating the bottom. You should try a smaller diameter burner. If you can afford it, getting a REAL restaurant stove or a Thermador professional home stove, both of which, have star shaped burners, which heat the entire bottom of the pan, is also a good thing to do. B)


On February 19, 2008 at 06:32 PM, SuseCookin said...
Subject: Cooking pots and pans
I am looking for information on Lifetime Cookware. I'd like an engineers perspective on the 12 element construction. The website for their stuff is cookwareamerica.com. The stuff looks really good. Any thoughts?


On February 19, 2008 at 07:18 PM, Dilbert said...
>>looking for information . . .

yup, won't get much info on that site. marketing pizzazz - no meaningful detail, no meaningful specifics.

Regal / West Bend is an established old line company, but they don't jump to mind when someone mentions "qualiity stuff"

there are several "exclusive" brands being marketed by the parent company with all kinds of fantastic claims. many of them are MLM schemes - probably cost 60-100 times its value.

not everyone is impressed:
http://www.nicolekruse.com/company_201.html?utm_source=Google&utm_medium=PPC&utm_campaign=lifetime%2Bcookware
http://www.tian.cc/2005/12/overpriced-cookware-by-classica-and.html


On February 20, 2008 at 03:10 AM, GaryProtein said...
There is no one best material for cookware. Cookware is a lot like shoes. It depends on what you plan on doing in it and your personal preferences. In a snowy winter you need ones that are tall, heavy leather and have deep spikey soles, for summer you might want sandals to stay cool, for temperate climates, you might want comfy sneakers and for a black tie affair, you need glossy patent leather.

As Dilbert said the type of pan you use depends on what you are cooking in it.


On March 06, 2008 at 06:45 PM, JT (guest) said...
Subject: NICKEL ALLERGY
I AM WONDERING IF THERE IS ANY NICKEL IN THE LARGE ALUMINUM COMMERCIAL TYPE WEAREVER STOCK POTS USED IN THE SCHOOLS FOR A STUDENT THAT HAS AN ALLERGY.


On March 06, 2008 at 07:40 PM, Dilbert said...
Wearever makes rafts and rafts and rafts of different styles, types, materials, etc.

the best approach would be to get the exact manufacturer's part number - hopefully some information is stamped somewhere on the pots - and contact them at wearever.com

to my knowledge, and I am not a metallurgist, nickel is not a common component of aluminum alloys - nickel is almost always present in stainless steel.

when nickel atoms/ions/compounds can leech out of stainless steel is a question for an expert - which I am not.


On March 10, 2008 at 02:12 AM, GaryProtein said...
Nickel can leach out os stainless steel in everyday items including stainless steel tableware (knives, forks and spoons)

Nickel can also leach out of coins. What happens when the child handles coins like nickels, dimes and quarters?

Has the child had nickel allergy confirmed by an allergist, or is it just a guess?


On March 16, 2008 at 04:42 PM, Gloria (guest) said...
Subject: Why does water tastes different boiled in different kettles?
I would like to choose an electric kettle to boil water, however, I am interested to know why water tastes different from different kettles. I am wondering if the material used in the different kettles, is the difference in taste of the boiled water. Is there a way to test to determine the metal is making the difference? Are there are reasons for the water to taste different?

I found this website, in a search to help me with these questions.

Thanks for all input.
Gloria


On March 16, 2008 at 06:00 PM, an anonymous reader said...
I use stainless steel cookware no larger than the burners to help in having even cooking. Then I place the cookware on a cast iron pan that I had in the oven while I was baking something else. This helps keep my food hot longer without buring more fuel/electricity.


On March 17, 2008 at 01:35 AM, GaryProtein said...
Subject: Re: Why does water tastes different boiled in different kett
Gloria wrote:
I would like to choose an electric kettle to boil water, however, I am interested to know why water tastes different from different kettles. I am wondering if the material used in the different kettles, is the difference in taste of the boiled water. Is there a way to test to determine the metal is making the difference? Are there are reasons for the water to taste different?

I found this website, in a search to help me with these questions.

Thanks for all input.
Gloria


The water tastes different from different kettles because of the differences in reactivity of the metal the pots are made of. Some stainless pots may have solders or fluxes that remain that can affect the taste of the water. A plain stainless steel pot wil probably taste best because stainless is least reactive and will have least interaction with the water as it heats and boils. My feeling is a an all stainless pot, not even one with a copper bottom is best. I have a Krups electric kettle and it makes fast, clean tasting boiled water.

Also make sure the clean out the pot occasionally even though only water is placed in it because in some areas, lime may deposit on the walls of the kettle.


On April 27, 2008 at 02:08 PM, an anonymous reader said...
Subject: Swiss Diamond Cookware and PTFE
There seems to be some confusion about Swiss Diamond cookware. It does not contain Teflon (TM). However, Teflon is merely DuPont's brand name for various polytetrafluoroethylene (PTFE) nonstick products.

Swiss Diamond contains PTFE, just not Teflon (TM) PTFE. The Swiss Diamond FAQ states this very clearly. If you believe that you are avoiding some terrible fate by using Swiss Diamond cookware instead of Teflon cookware, you are misguided. PTFE, regardless of brand name, will degrade and release small quantities of mildly toxic fumes -- not particularly harmful to humans, but they might kill a pet bird.

So, don't believe that Swiss Diamond is somehow safer than Teflon. However, both, when treated well, pose absolutely no health risks. Smoking oil on the stove is a far greater cancer risk than over-heated teflon. Buy your cookware based on how well it works for you, not groundless health claims. And get a range hood for your stove if you're really worried.


On May 08, 2008 at 06:03 PM, Socalgail (guest) said...
Subject: Bad Link on this Page
This link http://ww3.komotv.com/Global/story.asp?S=3615478 referenced in a post by TruthFinder on January 15, 2006 at 11:04 AM caused my PC to crash. Just thought you might like to edit the post.

Thanks,
Gail


On May 09, 2008 at 02:26 AM, Michael Chu said...
Subject: Re: Bad Link on this Page
Socalgail wrote:
This link http://ww3.komotv.com/Global/story.asp?S=3615478 referenced in a post by TruthFinder on January 15, 2006 at 11:04 AM caused my PC to crash. Just thought you might like to edit the post.

I tried the link on multiple computers and couldn't find any problems.


On May 29, 2008 at 02:15 PM, guest (guest) said...
Subject: Great Cookware articles
Here are a couple of cookware articles that I really like.

Essential Cookware - http://thebestcookware.blogspot.com/2008/05/essential-cookware-for-your-kitch...tml

How to choose frying pans - http://www.salamandercookshop.com/index.php?main_page=page&id=11&chapter=0


On November 20, 2008 at 07:38 PM, Justsmartliving (guest) said...
Subject: Sustainable Stainless Steel
A very objective analysis. Nice work.

We have been proponents of the benefits of stainless steel cookware in terms of sustainability for years. I personally wanted to call to your attention what the Specialty Steel Industry of North America (SSINA) says about the benefits of stainless steel in terms of sustainability.

We've paraphrased their comments here:
http://www.justsmartliving.com/blog/2008_10_01_archive.html

And their original article can be found here:
http://www.ssina.com/overview/features.html


On December 18, 2008 at 03:22 AM, kelly (guest) said...
Subject: vollrath carbon steel fry pans
i was gifted some vollrath carbon steel fry pans (no aluminum disk, all steel). had some performance issues I didn't really expect. even with some extensive pre-heating, on the 12", i have pretty dramatic hot spots on the largest burner I have... fry bacon, center of the pan is much hotter than the edges, results aren't pretty. stove is ceramic cooktop (unfortunately)... function of the stove or the pan? thinking the pan just isn't a particular good match for the stove i have but not sure.

I like the carbon steel pans for certain things, great for throwing in the oven, just not quite what i was expecting.


On January 17, 2009 at 01:46 PM, an anonymous reader said...
Subject: seasoning cast iron
I have several cast iron pieces, and am looking for information about seasoning. I typically use lard, as I find vegetable oil has a tendency to get sticky. Is it better to use a fat with a high smoke point? Or is a higher viscosity better to penetrate further into the pores of the cast iron? What is the optimal temperature to heat the pans to as you are seasoning? Any tips on making the seasoning last as long as possible?


On January 17, 2009 at 02:16 PM, Dilbert said...
Lodge is one of the better brands, here's their guide:

http://www.lodgemfg.com/use-care-seasoned-cast-iron.asp


On February 04, 2009 at 11:29 PM, aztraph said...
Subject: Titanium cookware
Does anyone have any experience cooking with Titanium pans, Pros, Cons. they're a bit expensive so I want to do research before I buy any.


On February 05, 2009 at 02:20 PM, Dilbert said...
aztraph -

indeed you should research the brand and its specifications very carefully.

a number of companies are marketing "titanium" cookware. aside from camping gear (which is just plain metal, lightweight) all of the brands I have checked use a sputter coating of titanium, which creates a sandpaper like surface, and the "holes" between the "grains" is filled in with PTFE - the generic name for Teflon (a DuPont trademark.)

most of the marketing hype will say "does not contain Teflon" - well, if I fill up my car gas tank with gasoline, not Exxon, what's the diff?

many marketing sites simply state its a proprietary thing - they don't say if it does, or if it doesn't.

also note the warranty info on many sites: if you cook too hot, cooking fats will coke on the pan and void the warranty.

note also the "safe to 500 degrees"- titanium will go a whole lot hotter than that, what's holding them back?

interesting link: http://www.naturalnews.com/021059.html

SwissDiamond now states:

Quote:

Do Swiss Diamond products contain “PTFE”?
YES! PTFE is the component that gives non-stick properties to the surface of the cookware and many other consumers’ products. Our patented inherent slippery coating is reinforced with Diamond Crystals which are amalgamated into a nano-composite (mixture of extremely thin particles). Thus it requires lower quantity of PTFE, much lower than most of other non-stick products.


at the basis of all the marketing hype and misinformation is the simple fact that PTFE is - so far as I have ever seen documented - the only durable "non-stick" compound in existence.

various "green pans" claim a silica based technology, which apparently does not last very long, judging by the consumer reviews.

see: http://dannyseo.typepad.com/my_weblog/2007/10/green-pan-updat.html

that thread also points out the need to be very aware of the site you are reading - as stated there, tv sales channels do not allow negative posts to remain - only the rave reviews.


On September 23, 2009 at 06:23 PM, Jersey (guest) said...
Subject: Cuisinart Chef's Classic Stainless clad cookware & oxida
I recently purchased a 17 piece of Cuisinart Chef's Classic Stainless clad cookware and am very unhappy with it. Virtually all the pieces now have an oxidadized inner bottom. I have never used more than med heat and have followed all directions to a "T". Is this something that just happens with this type of cookware? It is encapsulated on the bottom with an aluminum core sandwiched between stainless steel.
As soon as I cooked anything in these pans, an unsightly oxidation appeared where the food had been. It cannot be removed and is now part of the pans.
Please, engineers, let me know what's going on.
Thank you


On September 23, 2009 at 06:56 PM, Dilbert said...
it's certainly not something that "just happens with this type..."

according to their web site it's 18/10 stainless steel - and should not discolor, etc.

I've got stainless steel pans that go back two generations that are not discolored or oxidized in any manner.

I'd be tempted to contact them and ask what's up - do note that the warranty explicitly excludes "discoloration" - a bit of clarification with regard to "oxidation" would be helpful.


On September 23, 2009 at 08:16 PM, Michael Chu said...
Subject: Re: Cuisinart Chef's Classic Stainless clad cookware & o
Jersey wrote:
I recently purchased a 17 piece of Cuisinart Chef's Classic Stainless clad cookware and am very unhappy with it. Virtually all the pieces now have an oxidadized inner bottom.

Does this occur to all your stainless steel pans or only the Cuisinart? Is it oxidation (rust) or a white substance that has cemented itself onto the base of the pan? When you say it cannot be removed - what have you tried? I suggest Barkeeper's Friend and a soft sponge. If Barkeeper's Friend does not remove it, then there is something wrong. We can try to narrow down what it is once we find out a little more info.


On October 18, 2009 at 07:05 PM, Diana (guest) said...
Subject: Question about unlined copper
A few years ago I bought a hand-hammered unlined copper pot at a fair in Buenos Aires (I know - I have a good life). I have cooked caramel in it only a few times because there was a very metallic taste. I feel like this pan could be fantastic, as I saw many people street venders cooking candied nuts in it on the streets, but I am a little nervous about using it. I can find hardly any information about cooking with unlined copper on the web, and was hoping maybe someone here had some advice. Should I avoid it, can I pre-wash it with something, or should I search out a place to get it lined with tin? Thanks for any ideas people have.


On October 18, 2009 at 07:46 PM, Dilbert said...
"un-lined" copper is not a good choice for anything acidic - copper is fairly reactive to acid compounds - tomatoes for example.

un-lined "plain" copper is is frequently used in confectionery work - candies / sugar stuff / sugar panned toasted nuts.

it does not normally impart a metallic taste in those uses - which makes me wonder if it is an alloy, perhaps not solid copper....?

if you search of "retin copper" you'll find a number of smiths that can do that.


On October 28, 2009 at 04:32 AM, Doug (guest) said...
This was a very well written and researched article! After reading it I think I'll replace all my aluminum cookware and get some stainless all clad cookware instead. Thanks!


On March 06, 2010 at 01:33 AM, cludwig (guest) said...
Subject: Great article, but give carbon steel another look!
A really first rate article. This is the clearest, best researched article about the properties of various materials in cookware!! Thank you! I must say though that my favorite pan is my carbon steel French omelette pan. Julia Child mentioned in her book that one of the great French chefs used only carbon steel for omelettes. I thought that was enough of a recommendation to try it. My pan is a 2 mm thick 24 cm blued Lyonnaise shaped pan made by De Buyer. I've been using it for a month and I can say that I love it. (I've cooked so many eggs in the last month that my wife thinks I'm addicted)

The review of the metal properties is pretty spot on, but the point of carbon steel isn't thermal properties, it's surface properties. You have to use some type of fat with eggs (I used clarified butter), but the result is as close to non-stick as you can get with a surface that tolerates metal utensils and will last forever. Oh yeah, and this gourmet pan costs under $40.

A 2mm pan is heavy enough to have thermal properties that is not quite as good as a thicker cast iron, but pretty darn close. Yet it is lighter, slick and makes perfect eggs. There might be other pans that can perform just as well, but none that will last 3 lifetimes and only cost $30-40.

check out www.debuyer.com. www.chefscatalog.com carries a nice selection of de buyer pans, but they don't have the Force Blue line. I got my pan at World Market.


On April 27, 2010 at 09:42 AM, visitor (guest) said...
Subject: Need more examples!
You explain the science but that is just the "cause" and we need to know the "effect." For the thermal conductivity you mention practical examples such as hot spots and have those great images, but you haven't given practical examples for the heat capacity or diffusion parts. So what happens if I put a big steak onto a material with high heat capacity versus one with low?

Also you never talked about the transmission of heat from the cooking material to the food. Does that just mirror thermal conductivity of the fire to the cooking material? In other words if I have two almost identical pans made of magic materials where the only difference is that pan A has a low thermal conductivity while pan B has a high thermal conductivity, what would happen differently if I heated both pans up to 300 degrees F and put a big steak on each?


On April 29, 2010 at 10:19 AM, QUestioner (guest) said...
Subject: Math error or analysis error?
You say that aluminum and copper are the best "in terms of both holding and dishing out energy" because of their high thermal diffusion values.

But as you said
thermal diffusivity = thermal conductivity / (density and specific heat)

So if specific heat goes up then thermal diffusivity goes down. But specific heat is the ability to "hold energy." So then how can you say that a high thermal diffusivity means that a material can hold energy well?


On April 29, 2010 at 08:11 PM, Michael Chu said...
Subject: Re: Need more examples!
visitor wrote:
So what happens if I put a big steak onto a material with high heat capacity versus one with low?

In these idealized examples, two identical pans except one with low thermal conductivity (A) and one with high thermal conductivity (B):
A has a lower thermal diffusivity than B. Because heat capacitance is the same, both pans have the same amount of thermal energy to potentially contribute to the food, but A will cook slower than B. The steak will take longer to brown and cook through on A than B. The closest example I can come up with in the real world is a stainless steel (A) vs cast iron (B) pan, but it would have to be an exceptionally thick stainless steel pan or an exceptionally thin cast iron pan in order for the non-thermal conductivity variables to be somewhat similar. Usually, a cast iron pan has much more material volume (and thus total heat capacitance) than a stainless steel pan, so that makes this example a bit useless unless one can fine a sheet of stainless steel thick enough to match the heat capacitance of a cast iron pot...

In the second scenario (differing heat capacities) - this is actually one where a real world example could come into play. For the same material - let's do stainless steel - we have pans of different thickness. Thermal diffusivity of the pans are identical since the material has not changed, but heat capacity is higher on the thick pan because it has a larger volume of material and heat capacity = specific heat * specific gravity * volume of material. What happens when you stick a big steak on the thin pan and the thick pan is that cooking occurs at the same rate (same thermal diffusivity), but the pan with less heat capacity will "run out of energy" sooner than the other pan. If no additional heat is applied to the system, then it will stop cooking before the thicker pan. Considering the situation that heat (the burner) is added to the system, complicates matters a bit, but the end result is somewhat similar. The thinner pan will initially cook the same as the thick pan, but hot spots will form sooner than the thick pan as it begins to run out the energy that was initially stored in the pan and heating comes mainly from conduction from the burner through the pan material. The thicker pan will eventually reach this point, but the process will be a little slower as there is more of a "buffer".

I hope that helped a little - I apologize for the lack of examples.


On April 29, 2010 at 08:12 PM, Michael Chu said...
Subject: Re: Math error or analysis error?
QUestioner wrote:
So if specific heat goes up then thermal diffusivity goes down. But specific heat is the ability to "hold energy." So then how can you say that a high thermal diffusivity means that a material can hold energy well?

Yeah, that sentence is misleading. High thermal diffusivity means that the material can react to temperature changes rapidly (thus shedding or dishing out the energy stored in it rapidly), but it is heat capacity that determines how much it holds (like you said). It just so happens that in the small group of materials we examine in the article, they all have relatively high heat capacities. I'll think of a way to reword (or drop) that misleading statement.


On September 28, 2010 at 06:50 AM, an anonymous reader said...
Hey, brilliantly written atricle, but I have a question : Cooking spoons are also termed along with every other cookware as cooking utensils, right?
So, if we talk about cooking spoons then its material should have low thermal conductivity and high specific heat capacity, right? So that the spoon doesn't get too heated up too easily during cooking.
So my question is: Which one of the following should be the properties of cooking utensils?
a) High specific heat and low conductivity.
b) Low specific heat and high conductivity.
We can't chose (a) because pans and pots should have high conductivity and low specific heat and we can't chose (b) because cooking utensils are also spoons so then cooking spoons shouldn't have high conductivity and low specific heat.
But I have to choose an answer, this is a very important college exam MCQ, what should I do?
I hope someone answers, I'll be waiting!


On September 28, 2010 at 01:40 PM, Michael Chu said...
Anonymous wrote:
So, if we talk about cooking spoons then its material should have low thermal conductivity and high specific heat capacity, right? So that the spoon doesn't get too heated up too easily during cooking.
So my question is: Which one of the following should be the properties of cooking utensils?
a) High specific heat and low conductivity.
b) Low specific heat and high conductivity.
We can't chose (a) because pans and pots should have high conductivity and low specific heat and we can't chose (b) because cooking utensils are also spoons so then cooking spoons shouldn't have high conductivity and low specific heat.

I think this comes down to definition. What is meant by "cooking utensil"? I usually think of utensils as separate from cookware (pots/pans) so I'm thinking spatulas, spoons, stirring sticks, etc. But I understand there are parts of the country and world that call everything a cooking utensil. In that case, it's a stupid question since a spoon and a pot serves two completely different purposes - so how can the question be answered correctly?


On May 03, 2011 at 01:34 PM, MikeB (guest) said...
Subject: just what I was looking for in cookwear material comparison
Thanks so much for this very thorough explanation. It was exactly what I was looking for with the perfect mix of details and explanation. Again, thank you for takign the time to due the work and post it on the web. One engineer to another: Well done!


On July 13, 2011 at 11:21 AM, an anonymous reader said...
Subject: new materials
I wonder how titanium fits in to the picture, I know it's a poor conductor but boil tests online show it being as good as aluminium - not possible surely?


On July 13, 2011 at 01:48 PM, Michael Chu said...
Subject: Re: new materials
Anonymous wrote:
I wonder how titanium fits in to the picture, I know it's a poor conductor but boil tests online show it being as good as aluminium - not possible surely?

Titanium's thermal properties are similar to stainless steel, but titanium is much stronger and most titanium cookware (designed for the camping and backpacking community) is extremely thin. In fact, when compared to equivalent aluminum camping cookware, the heating surface of the titanium pot is thin enough to produce similar heating times as that of aluminum (important when trying to conserve fuel). The big downside with such a thin pot? Hot spots. But, when camping heating food quickly in light cookware is more important than heating food evenly.

P.S. There is a little more to it than just a thin base - the thickness of the sides walls and rim of the pot can have an effect on water heating times because while the water is heating, the sides of the cookware are also heating. Aluminum will dissipate that heat faster than titanium, so boiling a completely full pot will probably be more advantageous to the aluminum cookware vs the titanium. (A half full pot will essentially have a tall ring of metal above the surface of the water acting as a radiator which will slow down the boil time. The efficiency of that radiator will depend on the design, mass, thickness, and material of the sides of the pot.)


On September 22, 2011 at 11:54 PM, ellie (guest) said...
Subject: Anodized Aluminum or Stainless Steel w/ Aluminum Alloy Core?
Thanks for the great article. I'm trying to decide between two Cuisinart sets - one is Anodized Aluminum, and one is Stainless Steel with an Aluminum Alloy Core. Any advice for me?


On October 09, 2011 at 12:08 PM, okapizoo (guest) said...
Subject: Demeyere cookware
I have just purchased a Demeyere granite-coated frying pan called Controlinduc ($240.00 for an 8") as I read on the internet that it can be used on induction, gas or electric but, on reading the cardboard cover that was wrapped around it, it reads as follows: "The Controlinduc function only works on an induction hob. We strongly advise against using this product on any other heat source, as the pan would heat as a normal pan but the Controlinduc function will not work, with the risk of overheating and burning the food in the pan". I wonder if you could give some explanation of whether or not I can use the pan on a regular electric stovetop?


On October 10, 2011 at 08:36 PM, Michael Chu said...
Subject: Re: Demeyere cookware
okapizoo wrote:
I have just purchased a Demeyere granite-coated frying pan called Controlinduc ($240.00 for an 8") as I read on the internet that it can be used on induction, gas or electric but, on reading the cardboard cover that was wrapped around it, it reads as follows: "The Controlinduc function only works on an induction hob. We strongly advise against using this product on any other heat source, as the pan would heat as a normal pan but the Controlinduc function will not work, with the risk of overheating and burning the food in the pan". I wonder if you could give some explanation of whether or not I can use the pan on a regular electric stovetop?

You can definitely use these pans over electric or gas ranges. They will function like a normal high-quality pan.

These pans supposedly contain a magnetic layer that loses its magnetism once it reaches a mid to high temperature (around 485F). If it does do that, then the induction cooktop will stop working and the pan will begin to cool eventually regaining its magnetic properties which will allow the induction cooktop to heat the pan again (causing the pan to maintain temperature around 485F). Demeyere recommends using the pan on induction because they think this feature makes the pan superior to a standard pan and using the pan on any cooking surface except for induction makes it perform like a standard pan. There should be no safety/structural concern to using the pan on an electric cooktop aside for the inherent problems that would be present with any other pan.


On February 29, 2012 at 04:38 AM, Patchouli (guest) said...
Hi, just read the excellent article. I have a question: Is there any difference in the thermal conductivity of aluminum once it has been anodized?
Thanks.


On February 29, 2012 at 01:42 PM, Dilbert said...
anodizing is a surface treatment - so technically perhaps a few tenths of a thousandth of a percent . . . essentially no.

anodizing does change the color and light/dark color absorb radiant heat differently - you would notice that effect.


On March 01, 2012 at 03:05 AM, Patchouli (guest) said...
So, yes and no ?

I was thinking along the lines of the fact that anodizing makes the metal harder, and being harder it is perhaps more dense, and being more dense it would perhaps affect the time taken for thermal diffusion.

But like you say, maybe it wouldn't be noticeable.

e.g. the difference between say, all-clad MC2 and all-clad LTD2. (mind you, with all-clad I believe there's an actual thickness difference between these two lines as well).

I'm just trying to think like an engineer. :)


On March 01, 2012 at 12:22 PM, Dilbert said...
in theory every alloy and every different combination of "clad" will have a different coefficient.

I haven't see manufacturers publish actual data for their pans. but the difference in the "pure" metals is so great that a little bit one way or the other is not going to make a lot of difference.

the "numbers" vary depending on units, but for:
Aluminum 136
304 stainless 8

with aluminum 17 times "more conductive" than stainless - the overriding effect is due to the basic metal - coatings & cladding aside.


On March 02, 2012 at 02:34 AM, Patchouli (guest) said...
Thanks. I'm currently looking into replacing my current s/s clad 11" casserole/rondeau pot that I use to boil things in (e.g. potatoes, pasta, corn, asparagus, etc) with something that heats up faster.

I'm trying to decide what would be the most conductive and fastest material for the purpose of bringing water to a boil. Even if I can just shave off a minute or two in the boiling time, I would be interested in getting whatever is the fastest pot. I'm guessing copper would be the fastest, followed by straight gauge alumnum, followed by a disk bottom pot?

is there a way to make an educated guess beforehand? Or iare there so many variables involved that it's a matter of trial and error.


On March 02, 2012 at 05:06 AM, Dilbert said...
silver conducts heat better than any other known element (to date)

if you can afford a solid silver pots and pans, I'd like to introduce you to my daughter . . . .

>>I'm trying to decide what would be the most conductive and fastest material for the purpose of bringing water to a boil. Even if I can just shave off a minute or two in the boiling time, I would be interested in getting whatever is the fastest pot.
<<

after silver copper is the "fastest" material.

I'm not sure I can understand how shaving 60-120 seconds off the time to boil a specific volume of water on a 'same' burner could justify the cost difference of Walmat cheepie stainless to $multihundred copper - but heh, it's your kitchen.

copper has other 'features' - got a bunch of it, love it.

with 14 copper pots/pans at my disposal, if I'm heating water to cook/steam corn, beans, asparagus, cauliflower, broccoli, summer squash - well gosh most anything . . . I don't reach for the copper, I get out the old cheap thin 'worthless' stainless steel.

if I'm fixin' a roux, yeah you bet the copper pans are nbr 1 on the grab list.


On March 05, 2012 at 07:27 PM, Michael Chu said...
Dilbert wrote:
silver conducts heat better than any other known element (to date)

Here's my completely unhelpful comment on thermal conductivity - diamond beats silver. Maybe in the future we'll have the technology to produce a diamond bottom cooking vessel.

Anyway, a more constructive comment would be that I find that using a thin stainless steel pot is the fastest way to transfer energy from a standard burner for the purposes of boiling water. We don't care about hot spots, just about transmitting heat into the pot as rapidly as possible. A thin, highly conductive metal would be better, but, in general, these highly conductive materials are made thicker because they need to hold more heat energy due to how rapidly they heat up/cool down.

If you are flexible with what burner you want to use (and not necessarily the one on your range), then getting a countertop induction cooktop and an induction ready pot will usually yield the fastest possible water boiling time because the electrical energy is converted to heat energy extremely efficiently. My $100 1800W induction cooktop generally boils water about 20% faster than my 17,000 btu gas burner. (My notes show an average time of 12.5 minutes to bring 3-qt of 40°F water in a 6 qt stock pot with lid on to a rolling boil with the induction cooktop while the gas burner in the same scenario took 15.67 minutes. Boiling times should be shorter in practice because most people don't start with refrigerated water, but I did for my tests because then I could keep the starting temperature constant through the testing.)


On March 06, 2012 at 05:03 AM, Jim Cooley said...
I'll follow up on what Michael said about an induction cooktop.

A friend in India has a 2500 Watt induction cooktop (They run 220 V) and that damn thing is so fast it's amazing!

I WANT ONE!

She can boils two cups of water at room temp (30 C°) in about 80 seconds, using a nothing more than a dented old stainless steel (well, it can't be all THAT stainless) pot.


On June 19, 2012 at 10:40 PM, gmt1155 (guest) said...
Subject: Cookware Materials
Do you have any knowledge of 316Ti ?

I use this cookware especially because it does not have corrosion leaking into my food.


On June 30, 2012 at 07:45 PM, AuntieMame58 (guest) said...
Subject: Cookware Post
I so wish the very thoughtful and informative post on cookware comparison had included the finest of cookware. That being 2.5mm copper lined with silver. Would you kindly post regarding this because it is astonishing and unrivaled in its excellence.

Thank you. :)


On June 30, 2012 at 08:22 PM, Dilbert said...
Auntie -

who makes a copper pan that is lined with silver?


On June 30, 2012 at 09:13 PM, IronRinger said...
And who can afford it? Premium stainless steel is out of my price range....


On July 04, 2012 at 11:02 PM, an anonymous reader said...
Someone asked about Titanium pots. What exactly does your manufacturer mean by that?

Backpacking shops sell pots made from titanium metal. These are very light weight, because the metal has a low density, and is strong enough to be kept thin. They also tend to have a conventional nonstick coating. These are good for boiling water when ounces count in your backpacking gear, but that's about it.

There is something else that is labeled as titanium, but is really just a nonstick coating that includes a titanium ceramic. It's a sales pitch just like the diamonds of Swiss Diamond.

I looked up 316Ti. This is a stainless steel (like the common 18/10) with some added molybdenum to improve corrosion resistance in chloride environments (less salt pitting?), and a bit of titanium, which improves stability above 800C. So the Ti part adds nothing in home cooking applications.


On December 20, 2012 at 03:21 PM, Tom Reynolds (guest) said...
Subject: Stainless steel - the best
I prefer stainless steel, because it is non reactive (I mean you can cook EVERYTHING in it) Ok, has a poor heat transfer, therefore one should invest in it once. But only once. It last for a lifetime if you buy a good one. You only need to get some nice wine glass and you will be fine


On February 28, 2013 at 03:41 AM, MarKoz (guest) said...
Subject: Warping/Type of Cooktop
I have been disappointed in the combination of "clad" cookware and my glass top stove.

I had purchased some Analon 5-ply SS/Al cookware as well as two Vollrath Tribute 3-ply fry pans. All the fry pans have warped notwithstanding that I use a grill surface thermometer to measure the temperature of the pans as they preheat. The 14" Vollrath (which is heavier gauge than the 12") held out the longest, and did not warp for about 2 years. The degree of warp is very slight, but on a glass top stove it is problematic.

Stainless steel with aluminium discs welded to the bottom have held out the best for me (so far). Wish I could go with gas, but that is not an option for me.


On June 16, 2013 at 04:11 PM, Keith Emms (guest) said...
Subject: cookware
I have been cooking professionally and domestic for over 35 years.
I have been using Rena Ware for that time, and still do. I have never met anyone who can replicate food done in a partial vacuum, using alternative methods.
Let alone the health benefits. The cookware looks as it did new, and to admit any bias, I sold it door to door for 2 years. It's carbon steel encased in Stainless. Fast, even,.....and works perfectly on the new induction tops.
Uses very little heat, reproduces colour, taste, and nutrition in cooked vegetables and fruits. Eliminates a large percentage of shrinkage in meat.

I now have a large sous vide system from Freshfood Solutions for doing the meat and fish proteins,......but the vegetables,......I've been doing that sous vide for 35 years!!!
Cheersk


On June 16, 2013 at 06:26 PM, Dilbert said...
waterless cookware. . .
oh the health benefits - only to the financial health of the MLM organization.

http://www.dailyfinance.com/2010/07/15/rena-ware-to-pay-600-000-for-making-false-health-claims/
Earlier this month, the Washington state-based company settled with the attorney general's office, agreeing to pay more than $600,000 in refunds and other fees as well as make changes to its business practices.

In its complaint, the attorney general said representatives for the company told consumers their competitors' cookware posed serious health risks. They told consumers that Rena Ware promoted good health and could cure diseases, claims that the AG says convinced consumers to allow sales reps into their homes.Consumers who agreed to buy the products were offered financing with interest rates as high as 21 percent, the complaint alleges. They also were't told they had a three-day period to cancel their order, which is guaranteed under California law for door-to-door sales.

http://dca.lacounty.gov/artRenaWareSettlement.htm
Rena Ware International, Inc., a company based in Redmond, Washington, agreed to pay more than $600,000 in fees and refunds to victims. Rena Ware must also have an independent overseer makes sure the company no longer uses false information or high-pressure sales tactics to lure customers.
http://www.consumeraffairs.com/news04/2010/07/ca_cookware.html
California Attorney General Edmund G. Brown Jr. today announced a settlement with Washington state-based Rena Ware International, Inc., which "made fraudulent and unethical claims" that its high-priced cookware could cure diseases such as diabetes and heart disease. The company agreed to pay more than $600,000 in refunds and other fees.


If you want to complain against Rena Ware or any other business, contact DCA:
Address: 500 W. Temple St. Room B-96 Los Angeles, CA 90012.
Phone: (800) 593-8222 or (213) 974-1452.


On June 20, 2013 at 02:42 AM, Just Lost (guest) said...
[b:33d024898e]Hellooooo all engineers!

Is there anyone here that can shed some light on Silvinox??
[/b:33d024898e]
I want safe 18/10 or higher SS with nothing coming off into the food - either in the form of unhealthy non-sticks peeling off into our cooking OR any chemicals "leaching" into it. We gave up non-stick years ago after our parrot died & came to find out that those pans were the culprit...

Primarily I only want really SIMPLE cookware. I already use alot of carbon steel wok type things but I really want some gorgeous SS!! With copper core *only* no aluminum anything! I just hate aluminum! I know its great for conduction but for my cooking it doesn't help it ever and sometimes it actually hurts it! Mostly high heat Indian dishes so its LOTS of heavy duty spices and acids.

I'm pretty much focused in on Sitram Catering line bc its simple 18/10 SS with simple copper core. One Paella Pan from Mauviel (again copper & SS only)

BUT - here's where the twist comes in....

I am **IN LOVE** with a few pieces of straight-sided Atlantis from Demeyer - BUT - just not sure about that Silvinox stuff its treated with OR that TripleDuc 3 layer bottom on the Atlantis line. I don't like Aluminum so if thats in the 3layer bottom on Atlantis that might be a deal breaker; but I can't find any specs on WHAT that triple layer bottom IS exactly on the Atlantis line. Im gonna call them and find out - but in the end its that Silvinox & not understanding what it IS and IF its SAFE that freaks me out!!

well - that said - Silvinox is some sort of chemical treatment but I just can't find anything online that explains it in detail -OR- anyone out there talking about it on a safety level.

I've seen the ''process'' on youtube and i've read that its supposedly some sort of reverse-plating type thing that actually draws out some impurities and makes the SS harder and ''more pure'' - but STILL - what does that all add up to in high heat cooking? Is some sort of ''chemical'' there that can leach out??

I'm gonna ask them when I call about the bottoms all I can about this ''treatment'' - but still - I just wanted to run it by u guys here bc maybe there's someone out there with a Chemical background that knows something about it...

Thank you so much for ANY input u have on the subject!! I really appreciate it!

Abigail

[/i]


On June 24, 2013 at 08:55 PM, Dilbert said...
Hi Lost -
the two common "grades" of stainless are 18/10 and 18/8 - that's chromium (highly toxic) to nickle (highly toxic)

so you'll need to reach a decision about the toxic scare tactics as they apply to alloys.
similar applies to aluminum. the health hazard from aluminum cookware was dis-proven by multiple agencies half a century ago; your mileage is obviously on the variance.

>>copper not aluminum!
you'll be pleased to learn that for a given thickness, copper conducts heat twice as "better" than aluminum.

Silvinox is a surface treatment of non-described detail. last I looked stainless steel was the answer to that marketing hyperbole maiden's prayer.

what does that do for high heat cooking? nothing.


On September 04, 2013 at 07:37 AM, Student said...
Great article, it helped a lot to me while writing my work for final exam. Added it as source, thank you very much Michael Chu, you are the biggest. Mariusz


On October 30, 2013 at 07:43 AM, JimD (guest) said...
Subject: Silvinox
Demeyere's process is proprietary, and nobody else seems to have figured it out yet. They use some combination of chemical solutions and "reverse" electroplating, which has the net effect of removing iron from the surface of the stainless steel, leaving behind a high-chromium layer. I suspect there's an annealing step as well, to consolidate the surface (i.e., remove the voids created by the removal of iron atoms.) The surface is probably treated to generate the chromium oxide layer that makes stainless steel stainless.

It's not a coating, and nothing is added to the surface. The stuff is expensive, but everything I've read says it's fantastically durable and easy to keep clean. I imagine one could eventually wear through the surface, given enough steel wool or scouring powder, but chromium is a very hard metal - the cookware should last pretty much forever given normal use and care.


On June 09, 2014 at 03:15 AM, deannel (guest) said...
Subject: Silvinox
Thanks for the post about Silvinox as I am interested in whether this is safe or not. So it is not a coating, but a process to remove iron, whereby there is less to react to food and the pan stays cleaner, shinier for longer. This process also increases the chromium in the pan. Is this safe? Is it the same type of chromium our bodies need, or is it different, possibly setting up health issues after regular use?

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