“All I want for Christmas is some deep knowledge about cooking prime rib.” I remember singing that song as a kid. Don’t you? No? Really? Well, maybe you’re singing it now. Perhaps you have read our posts about smoking a prime rib or perfectly roasting a prime rib for Christmas, and thought “well, shucks, those simple steps sure do sound like they’d lead to success, but what is really going on in there?” Lucky you. We’re going to tell you. If you want to make sure that your holiday rib roast is the very best it can be (and that’s exactly what we want to help you do), you should know more than just the bare minimum about how to cook it; you should really understand it.
Prime Rib Primer
What is a prime rib?
First, a prime rib can go by other names—beef rib roast, ribeye roast, or standing rib roast (so called when it is bone-in and can be roasted without the meat touching the pan)—but regardless of what it is called, it comes from the 6th through 12th ribs of a cow, sandwiched between the chuck and the short loin. It is primarily composed of the longissimus dorsi muscle that runs next to the spine. Because of its location high up on the back of the cow, this muscle is not well used. This lack of use means that this muscle develops to be much more tender than, say, the rear-leg muscles (the Round of beef): it is anatomically predisposed to tenderness.
Tenderness is, of course, only one of the attractive characteristics of this cut of meat. Perhaps the most notable feature of this cut is the deep, rich fat marbling. The “eye” of the rib is encircled by a ring of fat and connective tissue, outside of which lies the “lip” of the roast. Much of the whole roast is covered by a fat cap of varying thickness. It is those seams of fat that deliver rich flavor and a velvety texture, as well as keep the meat from drying out easily. 
Roast Selection
When selecting a rib roast, make your selection based on grade, price, and need
Picking out a rib roast at the store is a big deal. You want the best roast you can get in your price range, but you don’t want to come up short at dinner. So what should you buy and how much of it should you get? Let’s look first at grading and quality.
It’s a little known fact, but the method of grading beef by the USDA is solely based on fat marbling. The more thoroughly marbled the beef, the higher the grade. Higher graded beef will be juicier, more tender, and more flavorful, but it will also cost significantly more.
Buy the highest grade you can on your budget. If you can afford Prime grade, go for it! But Choice is generally a good intersection of quality and affordability.
You may have heard that Prime Rib refers to a prime-grade rib roast. This is not true—at least, not necessarily. The term “prime rib” predates the USDA meat grading system and is a reference only to the fact that it is the best part of the rib section. In fact in the USDA Food Standards and Labeling Policy Book, (pg 154), the USDA clearly states that, “PRIME RIB OF BEEF OR STANDING BEEF RIB ROAST FOR PRIME RIB: These products do not have to be derived from USDA prime grade beef” (emphasis in original).
Prime rib can be graded USDA Prime (it will cost you!), but it can also be USDA Choice or USDA Select. “Ungraded” meat cuts are also available, but if it were my decision, I’d get a little less of the better stuff than more of the ungraded.
So how much of this delicious, pricey beef do you need? That really depends on you and your guests, but as a general rule, figure about 1/2 pound of raw roast per person on a boneless roast, or one bone per two people on a bone-in roast.
Should I buy a boneless or bone-in rib roast?
Having reckoned grade, price, and guest-count, there’s still one more decision you need to make before you buy your roast: whether to go boneless or bone-in.
The debate has gone on for years, with the pro-bones arguing that the bones contribute more flavor, and, if pressed, insisting that the marrow was seeping in from the bones to the meat. This has been shown by J. Kenji López-Alt , a team at Texas A&M’s Meat Science Department, and Meathead Goldwyn to be untrue. The marrow in the ribs is the wrong kind for “seeping” and the bones themselves are pretty impenetrable—even to the gooey, tasty kind of marrow.
There is one way in which leaving the bone in can actually have an effect: as a heat buffer. Having a shield of bone and connective tissue on your meat can help to prevent overcooking. But if you like your roast rare to medium rare, it can actually lead to chewy, undercooked meat right near the bone.
In the end, you’ll have to decide based on your preference. A standing rib roast (which can be as small as two bones or as long as the full seven) is beautiful to behold, but more difficult to carve—you will probably just cut the bones off to serve it anyway. Yes, a bone-in roast will usually be cheaper per pound, but you will be paying for bone weight, which is not directly useful to you.*
On the other hand, boneless prime rib roasts are easy to cook, easy to carve, but cost more per pound. The choice is yours, but in the ThermoWorks kitchen, we most often cook boneless roasts.
* If you choose to get a bone-in roast, we recommend having your butcher prepare it “cut and tied,” with the bones cut off and tied back onto the muscle. This creates an easy carving situation while maintaining presentation and heat-buffering advantages. The bones are fun and tasty to gnaw on after dinner, or you can use them to make a beef stock.
How do I prepare a prime rib roast for cooking?
Ok, you’ve chosen a grade, a size, and a bone-status, and it’s getting time to cook. When we cook a prime rib, we’re looking for a uniform, edge-to-edge color and a delicious, flavorful crust. In order to get that kind of perfection, we need to take thermal control of the situation: we’ll want to sear it and roast it with precision and care, and we’re going to start with some string.
Tie it up
Tying a rib roast is very important. If you don’t know how to do it (YouTube will gladly teach you), have your butcher tie it for you. By tying the roast, you can create a more uniform shape and density along its length. This translates directly into more even cooking, with less chance of a gray ring around the inside edge of your holiday-table centerpiece. The tying also evens out the surface, allowing for better browning in the sear phase, and will result in a better looking finished product that is easier to slice.
To pre-rest or not to pre-rest
There is sadly no consensus on the appropriateness of a counter-rest phase in preparing a prime rib roast. For example, America’s Test Kitchen features three different methods for preparing a prime rib for roasting—1) salted in the refrigerator for 24 hours, 2) salted one hour in the refrigerator followed by pre-resting for two hours the counter, and 3) just pre-resting for two hours on the counter. Other experts go straight to the oven without a pre-rest. While others suggest putting the prime rib in the freezer before searing, to chill the meat. All this ambiguity can be perplexing.
We wanted to determine the effects of various thermal preparations prior to searing and cooking in a boneless prime rib roast. We roasted 5 boneless prime rib roasts, carefully monitoring the thermal state of each roast through our various stages of preparation, cooking, and resting. For two of the prime ribs, we rested the meat on the counter prior to searing and roasting. For three prime ribs, we placed the meat in the freezer prior to searing and roasting. We were curious to see which of these methods produced a finished result with the most desirable attributes of a finished prime rib—a crispy outer crust but with no discernible gray ring between the seared crust and the rosy pink meat inside!
➤Method
We started with four boneless prime rib roasts of roughly equal size and mass (each about three pounds), each with the same initial thermal conditions—coming straight from our refrigerator at ~38°F (3°C). We salted each of them (to flavor them and draw out excess surface moisture and encourage a better sear later on) and prepared our thermometers.
We fitted each prime rib with several Type K Thermocouple Mini Needle Probes (each 3.35-inch long), and connected these to a pair of ThermaData™ Thermocouple Logger KTC’s. These thermocouple-type thermometers are exceptionally accurate, and the loggers keep track of the data over time—perfect for watching the thermal situation in a roast. We placed each probe’s sensor at the middle depth (half-way through) each roast. One probe was in the centermost part of the roast, one ~0.5 cm from the outside edge, and the other evenly spaced between them.
➤Pre-sear treatment
We placed the first two roasts on the countertop, uncovered, in a room-temperature kitchen (~68°F [20°C]). Our goal was to let it sit for 2 hours or until the centermost probe temperature reached 50°F (10°C), whichever time was less. You can see how the temperautre of the meat was affected by this counter rest in the chart below.
The initial drop was due to needle re-arranging, but you can see that the center of the meat rose steadily from the initial 38°F (3°C) to the 50°F (10°C) that we wanted. It took the whole two hours, and these were only a three-pound roasts. (A larger roast will need 2-3 hours to come up to closer to room temperature like this.)
The other two roasts were placed in the freezer (~2°F [-17°C]), unwrapped and uncovered, until the outermost probe reached 29.5 °F (-1°C), a temperature we chose because we wanted the outside of the meat to start to get stiff and start to freeze before being seared. If we were going to protect the outside of the roast from graying, it stood to reason that chilling the region where the graying was most likely to happen just before introducing the cut to the intense heat of the searing pan was a good move.
Take a look at how the freezer rest turned out in the chart below.
The outer most edge (Center + 9cm) arrived at the low temperature we wanted in roughly the same two hours it took the counter-rest roast to come up to temperature.
Note, as well, that the three different temperature readings were closer together in the freezer roasts than in the room temperature roasts—meaning that there was less of a gradient differential when the meat was first introduced to heat—but that the cooler temperatures of the freezer roasts would have farther to go to arrive at our final doneness temperature of 130°F (54°C), or perfect medium rare.
➤Searing
Searing is an important part of roasting a prime rib. Searing the roast first will kill the surface bacteria, which is a nice touch, especially when you are roasting at lower temperatures. However, from a culinary standpoint, it is also very important. We get a bit of a nice crisp-meat crust from the sear, but more importantly, we create a coating of Maillard-reaction browning all over the roast. This natural flavor enhancement will baste the during cooking with tastier juices than if we had put it in the oven raw.
As the roasts neared their target pre-sear temperatures, we preheated our cast iron skillet to 500°F (260°C) as measured with an Industrial IR with Circle Laser (IRK-2) infrared thermometer. The probes were removed from the roasts immediately preceding searing so that we could sear all sides of the roast. Each surface of each roast was seared for 2.5 minutes, resulting in a “nicely browned” exterior. 
➤Cooking
We next re-placed our probes in each of the roasts and placed each in a well-preheated 225°F (107°C) oven. We also added a probe attached to a ChefAlarm® leave-in thermometer to simulate the controls normally used in a well-equipped kitchen. Lastly, we started a TimeStack® timer in “count-up” mode (by simply pressing the Start/Stop button) so we could keep track of how long each roast took to cook, to see if there might be any significant difference in cook times for each method. 
We cooked each prime rib to 125°F (52°C) so that approximately 5°F (2°C) of carryover cooking would get us to our finish temperature of 130°F (54°C) for a perfect medium rare. (If you like your meat more cooked, increase your pull temperature by 5–10°F [3–6°C]. This cut of meat really is not going to be as good above medium, however, so if your guests want darker meat, I recommend cooking to medium at most and then cooking individual portions further in a hot skillet or on a grill. Given that, people often ask for a prime rib temperature chart. Rib temps are the same as other beef temps, so that chart can help.)
Below are charts logging the temperature through the roasting process, including a half hour resting period after roasting.
This data tells us lots of interesting things. First, we can see the thermal gradients in the roast. as expected, the roast cooks from the outside in, creating layers of temperature that circle like tree rings going down into the meat.
Next, both roasts had maximum exterior temperatures that crested near 150°F (66°C) right when we were taking the roast out to rest. This is scraping just over the temperature where meat starts to turn gray—140°F (60°C)—but we see that 3 cm below the surface, we never really pass that mark critical temperature. If we have any gray ring, it will be because the meat that turned gray will have spent too much time above that inflection point.
The majority of the meat never goes above 130°F (54°C), which is the temperature at which protein fibers in meat begin to tighten and expel water. By keeping the temperature below this point, we’ve avoided the toughness that follows the constriction of the muscle fibers.
Another key to a good roast can also be found in this data: the length of time spent in the low-temperature zones. Meat naturally contains enzymes that break proteins down and create a more tender product. That’s what happens in the aging process. Those enzymes are more active at higher temperatures, up to a certain point. Calpains drop off around 105°F (40°C) and cathepsins stop working at about 122°F (50°C). the longer we can hover in a higher range below these temperatures, the more tender our roast will be.
- The counter-rested roast spent just 24 minutes within the range of double enzyme activity, and 113 minutes with any activity at all.
- The freezer-rested roast spent 35 minutes in the double-enzyme zone, maintaining a single enzyme action for the entire length of the cook—137 minutes.
With 11 extra minutes of double enzymes and 24 extra minutes of single enzyme action, the freezer-rested roast will have a chemical advantage in tenderness over the counter-rested roast.
As has been the case with every step thus far in our cooking process, the world of food is filled with contradictory methods for actually cooking a prime rib. Some say to blast the rib in a 400–500°F (204–260°C) oven and then shut the heat off for an undetermined amount of time. Others say to put it in an oven that can best be described as “warm” for 12-18 hours. For reasons that can be seen in our data, we maintain that a low oven (200-225°F [93–107°C]) with constant temperature monitoring is the best method. Because of this low-and-slow methodology, prime rib lends itself very nicely to being cooked in a smoker.
➤Resting
Once the roasts reached 125°F (52°C), we verified their temperatures with a Thermapen® Mk4 and rmoved them from the oven, covering them with aluminum foil to rest. All meats should be rested before cutting and serving them. The rest period allows for temperature gradients in the meat to even out, slowly cooling the exterior while the interior meat continues to rise in temperature. It also allows the muscle fibers to relax, reabsorbing the juices that they may have squeezed out in cooking. Our data above shows that during the rest period for both pre-cooking methods our exterior temperature dropped while the interior temperatures continued to rise slightly. Perfect.
➤Proof in the pudding
Once the ribs had rested, we sliced them open to take a look, and the differences were slight. Both of them were amazing. They were an even rosy pink across the vast majority of the meat. I had to get a ruler out to measure the gray rings—or what could pass for such. The counter-sit method had a gray ring that was roughly 3mm wide. It was hard to find. But the freezer-sit method was even better. It had a scant 1mm gray ring. They were gorgeous. 
When we performed taste tests on the roasts, the difference was slight but landed in favor of the heightened tenderness of the freezer method.
➤Crust?
One of the appealing features of a prime rib is the salty, seasoned, beefy outer layer. Many methods include an instruction to reverse sear (sear after cooking) your roast to increase the crispiness. We wanted to keep the flavor and food safety advantages of pre-searing but also wanted to see if a final sear could give us just one little of extra enjoyment. For our fifth rib roast, we followed the freezer method for pre-cooking. We set our ChefAlarm to 115°F (46.1°C) so that we would be able to move the meat to a hot oven with thermal room to spare. As the roast approached pull temp, we preheated a second oven to 500°F (260°C).
When the alarm sounded, we reset it to 120°F (49°C) and moved the roast to the hot oven. The roast started to sizzle and sing almost immediately. It became steadily more brown and crisp on the outside. When we reached the next alarm point (set lower to account for the increased oven heat that would drive more carryover cooking), we removed the roast, let it rest, cut into it, and were disappointed to find a very noticeable gray ring, up to 1″ thick. In the end, the 2mm thick crust that we got from the final sear was not worth the vast swaths of rosy pink meat that were lost.
We recommend a low, slow cook preceded by a good sear. Whatever crust you may get from the final sear is just not worth the risk to the rest of this exquisite cut of meat. And with the freezer method, you can get a harder sear without worrying about a gray ring from the beginning.
➤Seasoning
Before we conclude, I’d like to make a note about seasoning your rib roast. You paid a lot for this roast. Let it shine. Prime rib doesn’t need a lot to dress it up, and will, in fact, do swimmingly with nothing but salt and pepper. Some people are tempted (especially if they are cooking their rib roast in a smoker) to put all kinds of powerful spice rubs on their rib roast. If you feel so inclined, that is your choice, though this meat really shines with classic flavors. That being said, if you really want to dress it up and stay within a classic flavor palette, I recommend making a wet-rub of 3 cloves minced garlic, the minced leaves of 2 fresh rosemary sprigs, 1 teaspoon black pepper, 1.5 tablespoons dijon mustard, and 1/4 cup olive oil. Apply it after your sear and you will be hailed as a luminary of the kitchen.
Conclusions
Having considered thermal barriers, enzymatic actions, pre-and post searing, and other factors, we can say that the method of first salting and then partially freezing your prime rib, searing it in cast iron, and then cooking it in a 225°F (107°C) oven until the center reaches 125°F (52°C) and then letting it rest is the path to a perfect prime rib roast. It takes about 1/2 hour longer than the countertop method, and 2.5 hours longer than going straight from the refrigerator, but the difference is the difference between almost perfect and perfect. The slight bit of extra give in each bite, the difference between a 3mm and 1mm ring, the extra tenderness from the enzymatic aging—these differences are what separate a great rib roast from an exceptional prime rib. Thermal knowledge about your food gives you control over its production, and control over the outcome. So take control of your holiday dinner and make a roast your family will still be talking about next year.
Products Used:
![[alt text]](http://www.thermoworks.com/assets/images/products/ChefAlarm_Green-01.jpg) |
![[alt text]](http://www.thermoworks.com/assets/images/products/Thermapen-Mk4_Blue.jpg) |
![[alt text]](http://www.thermoworks.com/assets/images/products/TimeStack_Red-01.jpg) |
|---|---|---|
![[alt text]](http://www.thermoworks.com/assets/images/products/THS-113-185_generic-01.jpg) |
![[alt text]](http://www.thermoworks.com/assets/images/products/ThermaData-KTC_generic-01.jpg) |
![[alt text]](http://www.thermoworks.com/assets/images/products/IRK-2_01.jpg) |
References
Harold McGee, On Food and Cooking
Meathead Goldwyn, Amazingribs.com
J. Kenji López-Alt, SeriousEats.com, The Food Lab
U.S. Department of Agriculture, USDA Food Standards and Labeling Policy Book
Bob Donnelly says
Excellent article. I’ve never cooked Prime Rib before. I will now.
Martin says
Bob,
Thank you for the compliment, and I hope it goes well when you try doing a rib! Let us know how it turns out!
Dave S says
My nephew told me about the “X method” of cooking bone-in prime rib. You can Google it. The results are absolutely perfect every single time and it couldn’t be any easier to do. No searing first….
Martin says
Dave,
I just looked it up and while it looks like it could absolutely work, it doesn’t take many factors into account (starting temp of the roast, for instance), and because it’s based on time rather than temperature, it is by default a for of “flying blind.” If I were to try that method, I would be sure to use one—if not two—leave-in probes to keep an real eye on what’s actually going on. Thanks for reading!
Greg says
Thank you for the detailed information on the different methods. A question: In another of your articles on prime rib, the cooking temperature was listed as 225F. Just curious, have you noted any significant differences in the final results in avoiding the gray band and overall taste/texture with a slightly higher or lower cooking temp?
Interesting and enjoyable comments as to the many methods people have used to prepare a prime rib with fantastic results. For larger groups, rather than buying one larger roast ( 10+ lbs), I’ve cooked two, smaller ones – love the end pieces so twice the joy! I’ve used an overnight refrigerated seasoning method ( inserted slivers of garlic around the meat and a light rosemary/salt/pepper) rub and the countertop warm up before cooking but will try sear and the lower temp approach this year.
Getting up the nerve to try my hand at smoking a $100+ roast using the tools I have from Thermoworks. Happy Holidays!
Martin says
Greg,
Thanks for your comments! We have listed 200°F as the cooking temperature before, and now 225°F. Keeping it in the “low and slow” realm is the important thing to do. If you have it already, it would be a good idea to temp your oven with an air probe, you may find that it is up to 25°F off already!
By the way, buying 2 smaller roasts is a great way to handle larger crowds! Yes, you get double end pieces (also my favorite), but smaller roasts are much easier to sear.
Again, thanks for reading and get in touch if you have questions about daring the smoker!
Good luck!
Greg says
Thanks for the good point on the empty oven temp check. Ours is a newer gas fired oven and uses convection method for roasting – but certainly not a professional model/brand. I have Dot and Smoke to help me do the oven check and an MK4 to boot for the roast.
res says
excellent, but one important modification was not addressed, which interested me.
using indoor oven stove indoors.
bbq with propane,
bbq with natural gas
bbq with charcoal
bbq with charcoal wood chips-(cherry, etc.). direct heat
bbq with charcoal wood chips-(cherry, etc.), indirect heat
bbq with charcoal wood chips-(cherry, etc.), indirect heat with water pan..
i have bbq prime rib with charcoal, wood chips-(cherry chips). indirect heat with water pan, using thermoworks temperature equipment which i must say is a must and it had a delightful flavor but i am sure you will offer more promising techniques in cooking prime rib improving the natural flavor..
.
Martin says
Res,
The thermal principles involved in each of the cooking methods you mention are the same. A mastery of any of the techniques will allow you to create a proper thermal environment for the low-slow cooking of a prime rib. You may be interested in out piece on smoking prime rib!
rick says
“When the alarm sounded, we reset it to 120°F (49°C) and moved the roast to the hot oven. The roast started to sizzle and sing almost immediately. It became steadily more brown and crisp on the outside. When we reached the nest alarm point (set lower to account for the increased oven heat that would drive more carryover cooking), we removed the roast, let it rest, cut into it, and were disappointed to find a very noticeable gray ring, up to 1″ thick”
1. What is meant by the phrase “the nest alarm point” – not used elsewhere in your article.
2. You fail to mention how long the roast was under the broiler. Perhaps a shorter time would yield acceptable crust and less thermal pressure in the spinalis dorsi?
Of note, Serious Eat’s J. Kenji Lopez Alt, has videos testing and recommending “reverse-searing” methods.
There also recommendations of doing both pre and post sears.
Finally, searing methods may also lead to different results. I’ve seen using chimney starters, Searzall device on propane torches etc.
Martin says
Rick,
Thank you for reading and for your comment. “Nest alarm point” should have been “next alarm point,” (i.e. the nest time the alarm sounds) an edit I have made in the post. Thak you for catching that and I apologize for the confusion!
You are correct that a shorter time may have yielded better results. In answering the many comments on this post, I have come to see some mistakes I may have made, including moving the roast from cooking directly to oven searing. A cool-down period may have saved it by, as you say, reducing the thermal pressure.
Thanks again and happy cooking!
Ron says
I prefer the “reverse” method: Essentially low-and-slow to desired temp. Remove roast and crank the heat to 500+(F) and return roast for 5-12 minutes to get the correct outer crust.
http://www.seriouseats.com/2015/12/step-by-step-food-lab-reverse-sear-prime-rib.html
-Ron, did somebody say Yorkshire pudding?
Martin says
Ron,
Yes please on the Yorkshire! The reverse oven sear I think can certainly work, if done correctly. Our error was perhaps having a second oven ready to go and moving the meat right into it. Removing the meat from the oven and waiting for the oven to come up to temp will give the roast a chance to cool, and moving it further from the gray-ring danger zone. Happy cooking!
Dave says
Nice write up. Two comments really. First, wish you had made and hammered home the point that cook time for PR is determined by chamber temp, starting temp AND thickness of the loin, not the weight. Lots of people mistakenly believe that since a 4 bone 8lb PR might take 4 hrs to cook, that a 7 bone 16lb PR would take twice as long.
Second, if you happen to have another loin laying around, try repeating the reverse sear method, but this time, let the loin rest for 30 mins after the initial cook, then blast it at 500 to sear.
Martin says
Dave,
Great comments! You are right about the time factor, and I should have hit that harder. I think I did address it rather well in a comment here responding to Don.
And you are probably right about the reverse sear: a counter rest allowing the meat to cool so that the sear has to re-energize the meat is a great solution. We’ll have to give it a try.
Happy cooking!
John says
This is exceptionally well done, with the obvious product mentions in place, but I love the science behind it. It doesn’t seem that many companies share the same infatuation as their customers for what their products are used for. Bravo, and I look forward to more.
– John
Martin says
John,
Thank you so much and thank you for reading!
Dr. Frederick Howard says
Great read! I’ve been a follower of Thermoworks, Meathead, J. Kenji López-Alt for awhile now with outstanding results! I have a tool belt that includes Thermapen Mk4, Smoke and other Thermoworks products too numerous to list. I’ve tried high heat roasting with great results in the past. However last year I did Prime Rib at 200 with outstanding results. You’re correct in that the gray band practically vanished as if it were done via Sous Vide. This year I’m doing a 4-bone Dry aged from Flannery Beef. I’ve got a Searzall as part of my tool kit and I think that I’ll use that for a pre sear instead of the cast iron. BTW you guys rock!! I’ve given away Thermapen’s like they were candy, no complaints whatever and you guys do stand behind your products. Hats off ???? to Thermoworks !!!
Martin says
Dr. Howard,
Thank you for your comments! We are happy to be a part of your toolkit and your kitchen. Happy cooking!
Gary Knighton says
Great information, thank you.
Don Hendrix says
This is a very interesting article. Using the freezer sit method how many minutes per pound did you roast the meat and how much kosher salt do you use? Thanks!
Martin says
Don,
I didn’t do any time calculations of minutes per pound, I only based the cooking on temperatures. There is a good geometrical reason for this: A rib roast can be idealized as a cylindrical shape, and heat will be entering the cylinder from all sides, but will be approaching the center of the cylinder from the circumference far more than the end faces. As we increase the size of the cylinder, we decrease the heat effect of the cylinder faces on the center until that effect becomes negligible.
So it is with a roast. A bigger (longer) roast (let’s say…8 pounds) of the same diameter as a shorter roast (maybe 5 pounds) will take heat to the center from the circumference of the roast more than the edges, but not significantly more so than the smaller roast, especially at these lower temperatures. A three-pound difference will not result in the same kind of cook-time differential in a rib roast as it would in, say, a chicken, the geometry of which significantly changes the surface exposure to heat. This is why w probe thermometer with an alarm is such a good idea for a roast like this.
All that being said, I used enough kosher salt to give the whole thing a nice coat A few tablespoons for a large roast should do. I usually just keep adding it until it looks “nice and salty.”
Thanks for your comment!
Dustin says
Recommended time spent in the freezer? Or, is it best to go by temperature, making sure area just under the surface is sub 32 degrees?
Martin says
Dustin,
Time is relative, as always. It is best to go with temperature. 32°F doesn’t actually freeze meat, so go a little lower. We cooled ours to 29.5°F, which was cold enough to really solidify the fat and start to freeze the meat itself. Use a probe thermometer about 1/4″ below the surface in a part of the meat that isn’t as covered with fat cap. Our roasts spent about an hour to an hour and a half in the freezer, but that will vary based on freezer temp and initial beef temp. Good luck with yours!
Michael K says
Love the science of this article, and the fact that you incorporated all of the Thermoworks products to demonstrate this! I have a sous vide, and have been wanting to try a prime rib cooked in a water bath. I am curious, though, if I cook it at 130 then do a reverse sear if the “ring” would be too big and enough heat would be applied to continue to cook the inside. Should I cook to 128 and then sear?
Just wondering what feedback, if any, you have for sous vide. THX
Martin says
Michael,
First, thanks for your comment and thanks for reading! The sous vide prime rib is actually a problem we have been considering in our demo kitchen, and you’ve hit right on some of the issues we’ve thought about. Here are my thoughts thus far on it:
First, a roast as big as a prime rib is going to take a LONG time to come up to temp in a sous vide bath, and that much time could lead to bacterial problems. Bacteria on the surface will eventually work their way down through the seams of the fat and meat in this marbled cut, and so first need to be destroyed. A quick blanch in boiling water before the actual cook would do that, and has been recommended by some for this purpose. But a pre-sear will also kill the surface bacteria and will give your meat a tasty Maillard marinade while it cooks. Your choice.
Next, there is the question of “pull temp.” With sous vide cooking, there will be NO carryover cooking. You set the temp of the whole piece of meat and you let it go until even the very center is at that temp. Because there will be no heat differential, there will be no carryover. This is excellent news for avoiding gray ring, because as long as you set it below the 140°F where meat starts to turn gray (like, for instance, 130°F for an excellent medium rare) you don’t have to worry about any gray in the meat from the cooking.
And that brings us to the final question of the sear. We found that the meat 1/4″ below the surface increased in temperature by about 25°F during a skillet sear. If you’ve cooked your meat to 130°F, you are risking a little gray in there, though as you saw from our data, we hit 150°F and had little to no ring. If you want an insurance buffer, let the roast cool outside of the sous vide bath for 20 minutes or so, and then sear it in a hot pan. The temperature reduction in the exterior of the roast will act as a buffer for the heat of searing.
If you decide to try it, we’d love to hear about it!
Ron says
I have always seasoned meats before searing. You recommend the opposite. Does the sequence differ greatly and why sear first? Thank you, great article- I’m trying your tenderloin article for Christmas and standing rib for New Years!
Martin says
Ron,
I prefer to season with the herbs after searing because I find they often just stick to the pan and not to the meat when I sear. I also like the fresh-herb flavor of adding the herbs afterward. If you are using a Montreal seasoning or just S&P, there’s no reason to wait until after the sear, as those flavors will actually wake up nicely in the sear, and the dry spices are more likely to adhere to the meat during the sear.
I’m glad you are giving these a try! let us know how they turn out!
Randy Ewers says
Thanks, excellent article ! I will give it a shot for Christmas with a massive 14lb boneless roast. I will cut it in half for easier searing.
I have 1 question, and also have summarized your process below for a “quick reference” if anyone wants them.
Question: What did you decide on salting? I assume salting it 24 hours in advance is the way to go?
Summary:
Roast Selection:
o Prime is better than Choice, but more expensive.
o 1/2 lb per person if boneless, or one bone for two people if bone-in.
o Boneless vs. bone-in is a toss-up, but they usually do boneless.
o For long roasts, may want to cut in half – easier to sear, and 4 crusty ends (delicious) vs. 2.
Cooking Instructions (for 3 lb boneless roast):
1) tie the roast up, even if boneless. If bone-in, cut the bones off but tie them back onto the muscle.
2) Salt liberally (should look “salty”, several tablespoons for a large roast)
3) Bring to fridge temperature throughout – 38F
4) Partially freeze, until outer edge reaches 29.5F – took them about 1.5 – 2 hours for 3lb roasts.
5) Sear in cast iron. Preheat cast iron to 500F. Sear 2.5 minutes per side (perhaps different for long cylindrical prime roast).
6) Add seasoning (optional) AFTER the sear so it does not stick to the pan. “Salt and pepper is all you need. Or make wet rub of 3 cloves minced garlic, the minced leaves of 2 fresh rosemary sprigs, 1 teaspoon black pepper, 1.5 tablespoons dijon mustard, and 1/4 cup olive oil. Apply it after your sear and you will be hailed as a luminary of the kitchen.”
7) Cook at 225. Use an air probe to confirm oven temp if you have one.
8) Pull at 125F (maybe lower for larger roast). We are shooting for final temp of 130F after resting. Exterior temp when pulled will likely be around 150, just where meat starts to turn gray (140F).
9) Cover with foil and rest 30 minutes.
Martin says
Randy,
Looks like a good summary! Salting overnight is probably just fine, a full 24 hours won’t hurt a thing. Enjoy and let us know how it goes!
Art Schwartzstein says
As between the freezer first or no freezer first, was the taste test a “blind” taste test. It seems like you might have been sufficiently influenced by the size of the gray ring and extra effort spent to find a difference that may not be noticeable. And, whether or not noticeable around the edge, has there been a blind taste test for the meat in the center? Thanks for the fun analysis.
Martin says
Art,
Yes, we did do blind tests on the center meat. The meat from each was delicious, but not all that different. As long as the cuts are of equal quality, and the centers are cooked to equal temps, the centers will be pretty similar. The edges are where a roast that is properly done starts to differentiate itself. Thanks for reading!
lourdes goodman says
This was a very interesting article, I especially liked the information about enzymes & what temps to keep in mind for that range to have that extra bit of help from them. I’ve made a roast with reverse sear twice before but time between makes me feel like a newbie everytime so I like to review info. I’m definitely trying the sear in pan first. Thank you!
Martin says
Lourdes,
I’m glad you liked this info. I think everyone feels like a newbie every time they cook this cut, because most people only cook about once a year, so you are not alone! I hope our post helps you with your next cook. Happy cooking!