What is the temperature plateau?
Most people when they roast a piece of meat in their oven, expect the internal temperature of the meat to slowly, but steadily, climb from the time they put the meat into the oven until the meat is ready. However, if you slow cook a piece of meat like a pork butt or a beef brisket which has lots of connective tissue in it, you will observe that the internal temperature of the meat steadily rises for a while, but then it stops. It will stay at some temperature, perhaps even fall a few degrees, for a very long time and then resume climbing. What you are witnessing is the temperature plateau which occurs when the meat gets to the internal temperature at which all that connective tissue starts to break down. When you slow cook a butt or a brisket, the collagen in the meat will be converted by the heat into gelatin. If you took high school chemistry, this is sort of like fractional distillation. At first all the heat going into the meat is raising the temperature of the meat. However, when