Now we all know that water boils at 212°F, right? But,
interestingly enough, even in a 250°F oven, you can greatly
affect the temperature of the water inside a pot by allowing
evaporation or not. This is because evaporation, the act of
converting water into steam, takes so much energy—it takes
more than five hundred times as much energy to convert
one gram of water into steam as it does to raise that same
gram of water’s temperature by one degree!
Check out this graph demonstrating the braising
temperature of a pot with the lid sealed versus that with the
lid left slightly ajar:
BRAISING TEMPERATURE VERSUS TIME