I just tried to answer a question about pot roast and looking at recipes I discover one that cooks the meat at 200 degrees in a sealed pouch for 3 to 3 1/2 hours.
There is a lot of reason to make a roast such as a prime rib at low temperatures since the inside of the meat will cook close to the same speed as the outside making an even color and temperature to the meat.
However, cooking something at 200 degrees for 3 hours will ultimately cook it through and through which is the purpose. But, does it make a difference if the actual temperature of the meat goes past the boiling temperature? Would it be better to cook it in a 170 degree oven since the steam pressure raises the temp to perhaps something just under boil?
Best Answer
Any increased steam pressure would raise the boiling point, not lower it. However, I doubt that you will be able to seal the pouch well enough to withstand any serious pressure.
What may cause boiling though, is the fact that ovens cycle on and off, especially at low temperatures. The amplitude of the cycles depend on how good your oven is. At 200°F, your pouch will probably experience above-boiling ambient temperatures during the on-part of the cycles. Of course, that doesn't mean that the contents of the pouch is above-boiling, but there may be.
However, I don't think that the braising liquid boiling slightly now and again is going to be a big problem. Sometimes when I've braised meat, there's been some boiling, and the results have still both looked and tasted great.