Bone in, frozen rib roast

We cooked a 22 lb chuck roast to serve at a buffet for about 70 people. We started with thawed meat. Since the cook time appears to increase exponentially with the <b>volume</b> of the piece of meat, we cut it into 5 lb chunks and vacuum packed them separately. <br /> <br />This was early in our SV experience and we did not have a SV machine yet, so we used a "cajun cooker" (sometimes called a turkey cooker), which is a propane burner that puts out lots of heat, to heat up water for a 50 gallon ice chest to a bit above the target temperature. Ice chests do not typically have insulation in the top since, in the intended use of cooling, the cool air does not rise. But for heating it does and you lose heat quickly. So we took a sheet of closed cell foam and laid it across the opening at the top before closing the lid. It worked well with a 1-2 degree F drop per hour. We kept a 30 cup coffee pot of water at temp to refresh the water in the ice chest. <br /> <br />Per our calculations, we left it in the chest for 4 days. We served it sliced in the heated jus and our diners told us it was prime rib. That convinced us to purchase an actual SV machine. We use it all the time now.

Hi Tom. A rib roast can definitely be cooked sous vide with the bones on. <br /> <br />Depending on the size of it, I wouldn't suggest doing it frozen. Once the food starts to get large the amount of time it takes to go unfreeze and cook starts to become very large. For instance, at just 3" / 76 mm thickness it takes an extra 1.5 hours to heat to temperature from the freezer. <br /> <br />I hope that helps some. <br /> <br />Thanks.

I cooked a 5 lb brisket from frozen in a single piece once. The problems encountered would have been similar to a similarly sized rib roast, except that the brisket should probably cook longer to render connective tissue than the rib roast. I use a 7 qt crock pot with thermostat for sous vide; it's slightly underpowered for these larger pieces of meat. To assure that the meat would come to temperature quickly, I started with the water bath several degrees above target temperature when the meat went in. Within 30 seconds the water bath falls below target anyway, and the meat shows no signs of over cooking. In fact, I topped off the cooker with boiling water from a teapot. The extra effort bringing the water up to temperature might not be necessary, perhaps I was too fussy, but the results were good.