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Dilbert



Joined: 19 Oct 2007
Posts: 1006
Location: central PA

PostPosted: Mon Sep 12, 2011 9:54 pm    Post subject: Re: Pans Reply with quote

brown sugar wrote:
Hey,
For a beginner thats a lot to take in! Any other way thats simple than doing all that?


toothpick.
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r2d2
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PostPosted: Mon Sep 12, 2011 10:04 pm    Post subject: pans Reply with quote

Chu,

Thank you for all the help. My friend was here and was very surp. at your web site and your help. But i said i wasnt going to ask any more questions,but he has one and i told him to use the calc. for that when u do that. He asked if depth difference say loaf pan 9x5 and smaller loafs to find out bake times best to use the form. we talked about right?

!st time at this site and love it ....I am spreading the news. You are very helpful in explaining. Thanks again
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yocona



Joined: 18 Mar 2011
Posts: 47

PostPosted: Tue Sep 13, 2011 12:56 am    Post subject: Re: Pans Reply with quote

Dilbert wrote:
brown sugar wrote:
Hey,
For a beginner thats a lot to take in! Any other way thats simple than doing all that?


toothpick.

Big smile My thoughts exactly.
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whiz baker
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PostPosted: Tue Sep 13, 2011 5:43 pm    Post subject: Pans Reply with quote

I am with you guys on the toothpick thing. The other way is just way to hard to figure out if you dont have the math skills..(not saying you dont). But I have never had to do any fig. on pans when used diff. ones always use the trusted nose and eyes and the toothpick. Michael Chu wouldnt you agree.?
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r2d2
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PostPosted: Tue Sep 13, 2011 6:36 pm    Post subject: Pans Reply with quote

Chuu,

sorry to ask more questions ....b ut this is the place to do it at.LOL.
Hey on the form. or calc. you listed before for the round, square, and rect. would the calc. or form. work if using less batter in a pan...I dont know really how to say it,I guess.. say like you use loaf pan and you use 2 smaller pan s less batter would i do the calc. using the size of pans..(total surface area) the same way?Bec. of less depth in smaller pans i thought maybe different way of fig. it? I hope u understand me.
Thanks again! Also cupcake tins do that indiv. times how many have?
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Michael Chu



Joined: 10 May 2005
Posts: 1620
Location: Austin, TX (USA)

PostPosted: Tue Sep 13, 2011 9:46 pm    Post subject: Reply with quote

Sigh... this thread is making me tired. Yes, of course, I agree with the toothpick method for determining doneness, but I thought the point of this exercise was prediction. Different tool - toothpick determines when you are done; prediction allows you to plan.

Prediction is almost always fraught with uncertainty and our attempts to predict the difference in baking times (if any) of round vs square vs rectangular pans is no different. However, we must be able to speak a common language, which in this case is middle school math and English. I am actually having difficulties understanding r2d2 and I'm not sure if it's because English isn't their primary language or due to their writing style/grammar/abbreviations. I think the last two questions were: (1) If a pan isn't filled all the way, do we still calculate total surface area the same way? and (2) When predicting cupcake baking times, do we calculate the surface area of a cupcake tin and then multiply that by the number of cupcake tins we are using?

(1) Yes - as I've shown in previous examples, you only calculate the total surface area of the batter in the pan. So, if the batter only goes up 1.7-in in the 9x13 pan, you don't use the dimensions of the pan, you use the dimensions of the batter in the pan: 9x13x1.7

If I've misunderstood the question and you are asking "What if we use less batter? (As in what if we make a smaller batch entirely?)" Then the answer is: when doing prediction calculations, you must keep the total batter the same. It is technically possible to make some (more inaccurate) predictions when varying amount of batter, but the math is a little more difficult and you must have already mastered the simpler examples which we have been discussing here before considering adding another variable.

(2) For cupcakes, just calculate the total surface area of each cupcake tin and multiply by the number of tins (assuming they are all filled to the same depth - otherwise you need to calculate each different one and add them up). But let me save you the trouble: batter poured in cupcake tins will be much greater in surface area, total surface area, and probably shallower in depth than in any other container. You don't need to do math for this. Since we have not made (and cannot make) any claims as to how much less or more cooking time surface area will contribute to reducing or increasing cooking time, we can only say that when the three conditions listed above (that a new container's surface area is larger, total surface area is larger, and depth is shallower) are met then the batter will bake faster. Since that is immediately and so obviously true with cupcake tins, it is very safe to say with confidence that cupcake tins will bake the same batter significantly faster than a round or square or rectangular pan.

How much faster? That's not something easily calculated with any sort of accuracy, but if the batter took 45 min to an hour to bake before, you can expect (depending on cupcake size) the same batter to cook in 10-20 min!
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r2d2
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PostPosted: Thu Sep 15, 2011 9:09 pm    Post subject: Pans Reply with quote

I too am tired..but when some one is trying to learn there are questions. I still have something not sitting right with me and that is if have two 8x8x2 and one 13x9x2 and do surface area it tells me two 8x8 will take less time. But when i do the volume on the two 8x8x2 i get 256 cubic inches=17 cups and 13x9 i get 234 cubic inches= 16 cups by the math both point to the two 8x8 to bake in less time of 13x9..is this right? 8x8 has 1 more cup in it.
could u please explain. Also when do surface area can your depth of batter have a little play in it,or would that throw it off? Like one pan say 1.7 and other maybe 1.5...little bit throw it off?

Thanks
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Dilbert



Joined: 19 Oct 2007
Posts: 1006
Location: central PA

PostPosted: Thu Sep 15, 2011 10:13 pm    Post subject: Reply with quote

well, just as soon as you get that all sorted out -

if you think there is some "magic" formula that says:
multiply the time for an 8x8 pan by MysteryFactor Q to know how long to bake in a 9 inch round - you can stop looking - if any numbnut came up with one it would not be accurate except for the one brownie mix the nut case baked, and only when baked in his house in the same pan in his oven at his altitude and on the same day. and if you use an extra large egg instead of a large egg, not gonna work either. and if the egg was straight out of the fridge vs. left on the counter, ain't gonna work either.

and there is also no "calculation" for x flour, y water, z eggs, etc = 36.345651 minutes of baking.

I would discourage you from 'baking by the clock' - look at any recipe - "or until done/ until a toothpick comes out clean" - there's multiple reasons for that.

by the way - now that you've gotten into basic geometry - do note that the volume of two 9 inch round pans two inches deep _exceeds_ the volume of a 13x9x2 rectangle. so the original "expert" was speaking through her hat.

small / slight / understandably off the cuff highly technical screw-up, but none-the-less - pursuing in a similar highly technical vein the inane volume/surface area theories - two 9 inch rounds compared to 13x9x2 is just not valid.

except of course that exceedingly few recipes specifying a cake pan of any shape or size will fill the pan to the brim. an nuts, there's another variable......

so, odds are, she was most likely quite right. were she into pies, then she might be a bit quicker on the pie are squared thing and avoided the technical boo-boo.

there's a lot of devil in the details.

go with the toothpick.
or, do as I do and go with the bamboo skewer - easier to poke with.....


Last edited by Dilbert on Thu Sep 15, 2011 10:46 pm; edited 1 time in total
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r2d2
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PostPosted: Thu Sep 15, 2011 10:34 pm    Post subject: Pans Reply with quote

Dilbert,

Why are u talking about cupcakes? Did read the post ..the one right before u posted?
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Dilbert



Joined: 19 Oct 2007
Posts: 1006
Location: central PA

PostPosted: Thu Sep 15, 2011 10:46 pm    Post subject: Reply with quote

there - I edited that out. perhaps that will make the whole situation clearer.
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r2d2
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PostPosted: Fri Sep 16, 2011 2:21 am    Post subject: Pans Reply with quote

wow,thats amazing.THANK YOU
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chefchemist



Joined: 02 Sep 2011
Posts: 1

PostPosted: Fri Sep 16, 2011 3:11 am    Post subject: pans Reply with quote

I don't see the point of arguing about the dimensions vs baking time as it does not apply well in the real world. Nothing beats common sense.

there are many factors that influence in the baking process.

These computation are good only for the classroom discussion in cookery and of less significance in the real world..

its only importance is it can give you something to think about , but whatever notions you have about it it must be tested in actual practice.

Take into consideration that even the type of product being baked, the formulation and process,,amount of liquid,, the nature of the pan( type of material being used; aluminum and glass baking pans are not similar in baking performance......

Even the nature of the oven, convection, deck type, traveling, Rotary, impingement type etc had an influence on the baking performance...
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Michael Chu



Joined: 10 May 2005
Posts: 1620
Location: Austin, TX (USA)

PostPosted: Fri Sep 16, 2011 3:38 am    Post subject: Re: Pans Reply with quote

r2d2 wrote:
I too am tired..but when some one is trying to learn there are questions. I still have something not sitting right with me and that is if have two 8x8x2 and one 13x9x2 and do surface area it tells me two 8x8 will take less time. But when i do the volume on the two 8x8x2 i get 256 cubic inches=17 cups and 13x9 i get 234 cubic inches= 16 cups by the math both point to the two 8x8 to bake in less time of 13x9..is this right? 8x8 has 1 more cup in it.
could u please explain.

Your error is in calculating the volume of both containers separately. The premise was that the recipe is the same and you are filling to different containers. Therefore, by definition the volume of batter is constant. I assumed you fill the 8-in all the way to the brim (2-in), calculated the volume, then (because you cannot magically have more batter if you pour it into the 9x13 instead) calculated how deep the batter would be in the 9x13 pan.
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Michael Chu



Joined: 10 May 2005
Posts: 1620
Location: Austin, TX (USA)

PostPosted: Fri Sep 16, 2011 3:48 am    Post subject: Re: pans Reply with quote

chefchemist wrote:
I don't see the point of arguing about the dimensions vs baking time as it does not apply well in the real world. Nothing beats common sense.

there are many factors that influence in the baking process.

These computation are good only for the classroom discussion in cookery and of less significance in the real world..

Yeah, I tried to explain that earlier - we don't know how long to bake anything using these calculations. We can only predict with some certainty or a lot of certainty (based on how large the deltas are) whether something will take longer or shorter to bake in one container or another (assuming the same materials and ovens are used), but not how much longer or shorter. This isn't quite just a classroom exercise as the knowledge that it will most likely take longer than the time written in the recipe could have a huge impact in planning, or if something likely to take less time is also important in when and how often you should check on the product. A container that causes the values to deviate greatly from the original recipe's means more diligence is needed on the part of the baker if this is the first time they are making the recipe and have not acquired any empirical data yet, while a container that results in roughly the same values (such as 2 9-in cake rounds when compared with a 9x13 pan) means they can probably relax a little and simply start checking 5 minutes before the recipe says it should be done. I find this sort of information invaluable, BUT the person using this information must understand that it is more or less a rule of thumb - very useful, but you have to know when to apply it. And to know that, you need some experience.

Also, it should be pointed out that for some (many?) people these calculations take too much time to figure out and is WAY more trouble than it is worth. For others who find basic geometry and algebra to be as easy as simple arithmetic, then it can be easily worth the effort (since the effort is minimal) for the additional piece of information prior to starting a recipe. If you are the former type of person, then you shouldn't be focusing on equations and what not. If you are the latter, then by all means have fun calculating away (I do it all the time - it's not unusual for me to pop up a spreadsheet as part of my prep) but remember these are inaccurate models and only provide hints at what might happen, so they should be used as such - hints.
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DrBiggles



Joined: 12 May 2005
Posts: 355
Location: Richmond, CA

PostPosted: Mon Sep 26, 2011 10:05 pm    Post subject: Re: pans Reply with quote

chefchemist wrote:
Nothing beats common sense.


Common Sense. Yeah, nothing beats common sense. Too bad there's only a few blessed with it.

xo, Biggles
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