o boil 100 ℃, but the following 100 ℃. Boiling water evaporates quickly, it rapidly absorbs heat.Fresh fruits and vegetables placed in a closed container, out of the air quickly, as the pressure continues to decrease, vegetable surfacewater begins to evaporate, the evaporation latent heat of vaporization taken away, so that fruits and vegetables down to a low temperature, it is sometimes also called evaporative pre-cooling.
Vacuum cooling for a large surface area of leafy vegetable effect is