Cooking For Engineers

[Dilbert]

see also: http://www.cookingforengineers.com/forums/viewtopic.php?t=329

Every year there is a rash of questions regarding prime rib aka standing rib roast - how to cook, how to serve, how to how to . . .

For those folks who are inclined to research before-the-fact, here's some tips/tricks/things to think about.
This is not a recipe or a method - there are many variables involved in producing a "good" standing rib roast aka prime rib. Regardless of what cooking/roasting method you use here are some issues that influence what/why/where/who and when things happens in various methods.

Quality of the Meat Itself.
"Prime Rib" is the name of the 'cut' and does not mean the beef itself has been graded "Prime" by USDA inspection. Prime grade is expensive - if it's too cheap to be true, probably is not USDA Prime grade. most of what one finds in supermarkets is USDA Choice. Labeling a cut of meat "Prime Rib" regardless of USDA quality grade is the sole exception permitted by USDA / Federal law regarding the use of the word "prime" on meat labels with the USDA seal.

sidebar: the eight USDA meat quality grades are:
Prime
Choice
Select
Standard
Commercial
Utility
Cutter
Canner

Big End, Little End - or "Pick-a-Number"
'The whole thing' rib roast would be ribs #6 through #12 - which one rarely sees in a supermarket. All seven bones aka 'the whole thing' would be (a) too big to fit in a standard home oven and (b) 30 - 45 pounds (14 - 21 kg). Info tidbit: rib bones #1 to #5 exist - but are closer to the shoulder and incorporated to to cuts from that area; #13 stays with the hind quarter.

The "big end" starts at the shoulder/forward bit of the cow (lower rib numbers); generally reputed to be slightly less tender than the small=loin end (higher rib numbers) because the shoulder muscles get more exercise.

Of course, there's the ever popular "center cut." There is no universal agreement at which rib number large / center / small begins. You may not have a choice - or information - in the matter unless you are buying from a butcher shop; I have never seen prime rib roast wrapped on a plastic tray with a label indicating big/small end or rib numbers.

- Bone in or Boneless. I always do on the bone; and I insist the meat is not cut / separated from the bone (and then tied back onto the bone...) pre-roasting. Bone moderates the cooking, preserves moisture, and in my opinion adds flavor. also makes a nicer presentation; boneless is simpler to slice at the table however bone-in is really not that difficult to cope with when carving / slicing. if you're looking for a drop dead prime rib result, go with bone in.

For bone-in one typically orders by the number of ribs - 3 ribs would be roughly 10-12 pounds (4.5 - 5.4 kg) from the big end; about 8-9 (3.6 - 4 kg) pounds from the small end. 3 ribs will feed four-five people, with leftovers.

Boneless prime rib roasts sometimes do not have all the muscle groups. If missing the outer flap meat you lose a tremendous difference in how the cut eventually tastes in your mouth. Stripped down boneless roast consisting of only the center muscle(s) will not produce a really good prime rib roast. Sliced at retail, it is often sold as a "boneless ribeye steak" - might be some fat around the edges, but that's it. Frankly it's a poor imitation of a real standing rib roast; if insisting on a boneless/fatless cut, I'd recommend looking at a chunk of tenderloin.

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Pix and definitions. There are four muscle sections in the complete roast:
Spinalis Dorsi
Longissimus Dorsi
Longissimus Costarum
Multifidus Dorsi



By "cap" I'm referring to the spinalis dorsi muscle that forms a crescent-shaped outer portion of many, but not all, rib steaks. It's acknowledged by real meat people to be the single best part of the beef there is. The rib "eye" proper is the longissimus dorsi muscle that forms the larger portion of most rib steaks and is also great eating, but not nearly equivalent to spinalis.

It turns out that the largest part of the cap meat spans ribs 8 to 10, which means that it's the MIDDLE of the rib primal that spinalis lovers should be asking for. As you move forward, both the cap and eye become smaller as their space is taken up by those other [tasty, but tougher] muscles.

Bone-in ribeye steaks are mostly composed of the longissimus dorsi muscle but also contain (parts of) the Longissimus Costarum and Multifidus Dorsi - depending on the trim. Boneless ribeye steak are usually just the Longissimus Dorsi.

The fat cap. Trimmed to lean the roast will have little fat on the surface. If you want the rendered fat for other dishes, picking a trimmed-to-lean roast is not recommended. If you need a lot of rendered fat, buy the roast with a very thick fat cap, trim the cap thickness to about 1/2 inch ( 12-15 mm ) and render the trimmed off fat separately. Trying to render the fat out of the internal sections of a roast cut will over-cook the meat - past rare, past medium rare, past medium to 'ruined.'

The reality of tenderness: even the best prime grade of a prime rib roast will have some connective tissue holding the muscle groups together. these remain more pronounced when cooked rare / medium rare. Just invite your guests to trim off / pull off anything not particularly tender and 'enjoy!'

Aging meat. Our butcher will (special order) hang and dry age up to 14 days. If I can't get that, I dry age in the home refrigerator for 5-7 days. One meat lover site did some comparison testing and found that, in terms of flavor, dry aging past ten days is an exercise in diminishing returns. Do not salt / season the exterior before or during dry aging. Salting alters the surface to some depth and can interfere with slowly reducing the water content of the meat and hence 'concentrating' flavor. There are big thick books written on this topic and zillions of opinions - so pick some that suite your own tastes - there is no "one and only one right way."

Cooking
The actually cooking bit falls into two camps:
- Low and Slow
or
- Hot and Fast ....
and
stuff like "in a hot oven for x minutes per pound, turn off oven, come back z hours later"

One will find hosts of horror stories ranging from "it was still RAW!" to "it was burnt to a CRISP!" for any and all of these methods. The horror stories all have one thing in common: roasting by the clock.
If you are going to do expensive cuts like Prime Rib - invest in a thermometer.

Be aware that oven thermostats are not noted for absolute accuracy. Errors of +/- 25'F (15'C) is not uncommon. Another issue is how consistent the oven holds the set temperature - the thermostat comes on, goes off, temperature varies. Not a serious problem for most things - but when the cooking period extends over hours - it can make a difference in timing.

There is a sound reason for the horror stories when cooking by the clock - i.e. so many minutes per pound.... heat does not penetrate into a lump of roast "by the pound" - heat enters a roast through the surface area of the roast. however, the quantity of heat required to cook a roast does depend on its mass i.e. the pounds. "X minutes per pound" only works if your roast is similar in size and weight to the recipe writer's roast. The ratio of mass to surface area varies with the diameter and length of the roast - which is why the minutes-per-pound can result in disaster. That ratio - area to mass - varies by more than 50% for "big end vs small end" of prime rib / standing rib roasts and gets even further out of whack comparing a big-end-five-rib size to a small end two-rib-size roast. Fortunately thermometers do not fib - so, invest in a thermometer.

Timing: if one puts aside the 'by the clock method,' how does one manage to get the roast done for the desired 'sit down & eat' time? Pretty easy, actually - minor discipline required. Keep a written chart / record; for us nerds, use Excel to turn that into a graph. You can easily see how fast the roast is coming up to temperature and make timely adjustments to the oven temperature to "hit" the sit down hour. I log the center temp every 30 minutes initially, then every 15 minutes as it gets over 100'F / 38'C. With 60-90 minutes remaining, the oven temperature needs only a 10-15F degree change (5 - 9C degrees.) Easy thing to do - not so easy if you wait until 10 minutes before you want it done - then find it's 20 degrees low...

The Same But Different:
"The thermometer read 130'F / 55'C in the middle but the outside was over done!"
Heat moves from the hotter oven to the cooler roast center. The rate at which heat moves depends on the difference in temperature - i.e. heat moves into the roast faster in a 400'F / 205'C oven than in a 200'F / 95'C oven. No surprises there - but the unanticipated result is . . . when the center temperature reaches 130'F / 55'C, the outer portion of the roast has become hotter (i.e. more cooked aka "over done") when done in a hot/fast roast temperature.

"There is no accounting for taste" - or "preferences" - as may be more accurate in this case.
Personally, I like a crispy skin, a more done outer edge, with a medium flap meat layer, and a hot pink center. The crisp stuff has a _lot_ of flavor and I like to mix a chunk of brown&crisp with the hot pink center stuff on a fork. Not everyone is of my opinion. So, if you like edge-to-edge hot/warm pink/red - you have to roast low and slow and long. there is no other way to get a uniform temperature / cooking degree across the entire roast cross section - well, I suppose sous vide would work but it lacks any crisping ability.

Which method is best?
Roasting "hot & fast" will result in a browner / medium exterior layer; it is possible; it does work - especially in restaurant type settings where they do dozens of roasts per day/week and have perfected the technique. Experience counts, for the home cook doing this type of thing once or twice a year, the marginal experience level may come back to bite ala' the 'horror stories.'
Another issue of preference is the pre-sear / post-sear method for making a browned crisped crust on the roast. Personally I always do the post-sear because (1) pre-sear changes the roasting period but (2) post-sear allows a what-you-see-is-what-you-got result. I also find that post-sear produces a crispy nature - which...if produced in a pre-roast sear goes away.... For the post-sear, I simply jack-up the oven to top broil and observe carefully - takes perhaps 5-7 minutes. Turn/rotate/flip as needed.

[SmartShabby]

uh, thanks for sharing that, It is very helpful.