Does leaving the lid on or off really make much of a
difference when cooking in an oven that’s supposed
to be maintaining a constant low temperature? Try
this quick experiment to see for yourself.Materials- Two identical pots filled halfway with water
- One lid
- An instant-read thermometer
Procedure
Preheat the oven to 275°F. Place both pots in it, one
with the lid on and the other with the lid off. Let the
water heat for 1 hour, then open the oven and
immediately take the temperature of each pot of
water.
Results
The water in the lidded pot should be at around
210°F, while the water in the uncovered pot is
probably closer to 185° to 190°F. Because of the
cooling effect of evaporation (it takes a significant
amount of energy for those water molecules to jump
from the surface of the liquid—energy that they steal
from the liquid itself, cooling it down), an open pot of
stew in a 275°F oven will max out at around 185°F.
Good news for you, because that’s right in the
optimal subsimmer stewing temperature zone.
Pop the lid on, and you cut down on the amount of
evaporation. Less evaporation means a higher max