Whole Boneless Prime Rib Low-and Slow Cook Time

[ctbrown]

Hi everyone, My fist post here.

I’m looking for advice on the cook time for a whole 19lb boneless prime rib that I plan to cook using the low-and-slow method, finishing with a reverse sear. It’s currently dry brining overnight in the fridge.

While I’ve made large prime rib roasts in the past with great results, I’ve always “winged it,” and the timing hasn’t been ideal—either finishing too early or taking much longer than expected. Plan to roast at 225°F until the instant read thermometer reads 115°F, rest for ~45 min and sear at 500°F.

Does anyone have tips for estimating the cook time more accurately, or should I stick to using a meat thermometer and adjusting as I go? Any insight on oven temperature settings and how long to anticipate before the sear would be especially helpful.

Thanks in advance!

 

[caseydog]

I've never brined beef before.

You can't trust time, you need to use a probe thermometer in the center of the meat until it reads 115F. You can get a wired probe thermometer at Walmart, or even at many grocery stores for about 40 bucks.

If you start early, and get done early, you can wrap your meat in foil, then wrap that in a towel or two. I put that in a cooler, and the meat stays hot for hours.

CD

 

[Gridzheh9]

I have cooked 3 prime rib roasts many years ago for my brother who got them every year from his company. The first two I cooked them at 300F for 35 minutes a pound and they came out perfect. The third one I used a meat thermometer and cooked it longer than 35 min per pound because it was not up to temperature. This was a mistake because the temperature kept rising after I took it out of the oven and it was overdone.
I have never cooked a roast at 225F so I don't have any experience with the cook times for that temperature. I just wanted to warn you that the temperature might keep rising after you take it out so you might pull it a little early; however, my experience was with 300F. I got those cook Temperature and times from the "Culinary Arts Institute Encyclopedic Cookbook" and they have never let me down.

 

[Andy M.]

I use the reverse sear method all the time now.
I recommend you cut your 19-pound roast down to three 6+ pound roasts. They'll cook faster and more evenly.
A roast of about 6⅓ pounds should take about 5½ or 6 hours. This includes: resting the roasts at room temperature for one hour, then cooking time at 225ºF (I aim for 125ºF), the resting period and the time to sear at the end.

However!! I use a thermometer in the meat during the cooking so I'm not guessing.

 

[Kathleen]

Welcome to DC! Please let us know how your roast turns out!

 

[pictonguy]

Yeah the reverse sear is what I do at home and the restaurant. Use a wired meat thermometer and rest for at least an hour covered. I like to season and leave in the fridge for up to 3 days but 24 hours give a decent result as well.

 

[medtran49]

I agree with Andy.

 

[caseydog]

I have cooked 3 prime rib roasts many years ago for my brother who got them every year from his company. The first two I cooked them at 300F for 35 minutes a pound and they came out perfect. The third one I used a meat thermometer and cooked it longer than 35 min per pound because it was not up to temperature. This was a mistake because the temperature kept rising after I took it out of the oven and it was overdone.
I have never cooked a roast at 225F so I don't have any experience with the cook times for that temperature. I just wanted to warn you that the temperature might keep rising after you take it out so you might pull it a little early; however, my experience was with 300F. I got those cook Temperature and times from the "Culinary Arts Institute Encyclopedic Cookbook" and they have never let me down.

That is carryover cooking. Always pull the meat at a lower temperature than what you want to serve. It will keep cooking another five to ten degreesF.

I've only done one rib roast, and did it on the pellet smoker at 250F.

CD

 

[ctbrown]

I've never brined beef before.

It's a dry brine, which basically means that you rub salt all over the roast and let it sit in the fridge overnight—essentially allowing the salt to penetrate the meat. It's a fairly common practice for prime rib and other roasts.

 

[ctbrown]

You can't trust time, you need to use a probe thermometer in the center of the meat until it reads 115F. You can get a wired probe thermometer at Walmart, or even at many grocery stores for about 40 bucks.

I plan on using a ThermoPro wired meat thermometer with two probes. I'm really looking for the approximate amount of time it will take to reach temperature so I know when to put it in the oven.

 

[ctbrown]

I use the reverse sear method all the time now.
I recommend you cut your 19-pound roast down to three 6+ pound roasts. They'll cook faster and more evenly.
A roast of about 6⅓ pounds should take about 5½ or 6 hours. This includes: resting the roasts at room temperature for one hour, then cooking time at 225ºF (I aim for 125ºF), the resting period and the time to sear at the end.

However!! I use a thermometer in the meat during the cooking so I'm not guessing.

Good point about breaking down the roast for even cooking and faster results. For me, though, keeping it whole avoids creating extra end pieces, which my family isn’t too fond of. Plus, I’ll be using a convection oven, which really helps with evenness. Thanks for sharing.

 

[ctbrown]

Here's a picture of the roast from last night, before it went into the fridge...

 

[dragnlaw]

But look at all the seasoning that those end pieces must have! I'll take them off your hands come carving time.

 

[ctbrown]

I found a YouTube that I think I will use as a guideline, where the guy is cooking a 12lbs roast in what looks to be a convection oven...

 

[caseydog]

It's a dry brine, which basically means that you rub salt all over the roast and let it sit in the fridge overnight—essentially allowing the salt to penetrate the meat. It's a fairly common practice for prime rib and other roasts.

Ah, I was thinking wet brine for some reason. Yes, I salt beef overnight, too.

CD

 

[caseydog]

Here's a picture of the roast from last night, before it went into the fridge...
View attachment 72113

Did you have to take out a loan to buy that thing?

CD

 

[dragnlaw]

No, he sold his first born. Wow - what a hunk a hunk a beef!

I dried a roast in my sister's cold cellar, uncovered for 3 days. Was fantastic. If you have a cold cellar or somewhere equivalent you don't even have to put it in the fridge.

 

[ctbrown]

Update:
I started the roast at 1 PM, placing it into a Bosch Benchmark Series 30 convection oven set to 225°F. At that time, the instant-read thermometer registered 38°F. By 5:48 PM, the roast had reached an internal temperature of 116°F. After letting it rest for about 30 minutes, the temperature rose to 128°F. To finish, I returned the roast to the oven for the reverse sear, temperature now set to 500°F, for approximately 10 minutes. The final internal temperature was around 130°F.

 

[dragnlaw]

@ctbrown Beautiful, just beautiful. Hope it's as tasty as it lookes.

Harumph, where are my end pieces?

 

[Andy M.]

That looks fantastic! Congrats.