Max time for a prime rib

Hey all, I’m going to be cooking an 8 lb prime rib roast and I wanted to know if there was a general consensus for the max cooking time. I’m going to be leaving the night of christmas eve and returning christmas afternoon so I want to have it cooking for those 18 or so hours without destroying it.

Blake, other than a stated expectation of not destroying your roast you provide no really useful information beyond your itinerary.

A similar question was asked yesterday and the posted response should cover the basics you need. It just a click away.

To cook competently using the SV technique we consider the thickness of a roast and the desired degree of doneness. Only those significant details can guide the selections of your cooking time and temperature. After you’ve paid for all that meat you selected, weight matters not. There are other details to consider such as aging, breed, animal nutrition ( Was the animal fed, or did it feed itself? ), and grade, but those factors go beyond the scope of this post. And i suspect most folks just don’t care about most of them.

If you are considering a cooking temperature in the mid to low 130s F, about medium-rare doneness, you can safely extend the cook time to suit your schedule. The meat should be only slightly more tender, but not yet mushy. In fact if your roast has a lot of the cap and deckle meat above the rib-eye you might enjoy the results of a longer cook and use it more often. Those pieces of meat are extensions of the tougher chuck cuts which are commonly SV cooked for 24 hours. Even the finger meat between the ribs on your roast will take on a tender deliciousness that you may want to discretely enjoy on your own. (Heh-heh.)

Many foodservice operations employ the SV technique of overnight cooking and achieve consistently superior results. The Appalachian BBQ industry really only exists thanks to smokey low temperature overnight cooking. So please feel confident in your successful prime rib roast dinner if you don’t receive enough responses to arrive at a general consensus this time.

If you are cooking at significantly higher temperatures over long periods of time you are going to experience increased moisture loss with subsequent meat dryness. Just so you know.

Thank you for the response, I apologize for the omissions. I am aiming for a rare-medium rare roast cooked at 131 degrees after an initial sear.

No apology required Blake. You are facing some entirely new cooking challenges. Most folks don’t realize they can’t continue their conventional cooking thinking with the SV technique.

And if you can afford the time a post-cook sear will enhance your dining results. The crust and sear flavours (the browning or Maillard reaction) will be significantly diluted during SV cooking, particularly one that long. Sear last whenever possible.

A tip: a diluted solution of corn syrup, water, with a two-finger pinch of corn starch brushed lightly over the roast will enhance the browning you get and reduce the required time and temperature. A 425F oven for five minutes should be plenty. Watch it doesn’t burn, you want browning, not blackening. Use just a little of that solution now, you aren’t glazing a ham or icing a cake.

Blake, you will soon realize one of the great benefits of SV is how it helps you overcome time constraints like your present one, but you absolutely need to plan ahead. You could have easily cooked your roast a week ago and enjoyed a stress-free weekend.

Make it a great holiday.


Thanks for the corn syrup/corn starch tip, Chatnoir! Have to remember when I do a roast.

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