the pressure to about double the normal air
pressure at sea level. This increased pressure
increases the boiling point, and high pressure
and temperature put together produce an
overall doubling or tripling of the heat
transfer rate into the meat, as well as an
extremely efficient conversion of collagen
into gelatin. Pot roasts cook in less than an
hour instead of two or three. Of course the
proteins get very hot and therefore squeeze
out much of their moisture; meat must be well
endowed with fat and collagen to end up
anything but dry.
At the other end of the pressure scale is
cooking at high altitude, where the
atmospheric pressure is significantly lower
than it is at sea level. The boiling point of
water is also lower (203ºF/95ºC at mile-high
Denver, 194ºF/90ºC at 10,000 feet/3,000
meters), and meat cooking more gentle — and
more time-consuming.
Microwave Cooking