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Although there is a direct relationship between temperature and pressure, freezing is a little different than
pulling a vacuum. Chilling a substance in a freezer doesn’t lower the internal pressure of the package in a radical way. The resins and such viscosity will increase like thick oil in the winter in your car. Take that same oil analogy.
Getting it colder thickens and slows its molecular motion but doesn’t affect its pressure very much. Cold things tend to get denser. Now take that same oil and reduce the pressure via vacuum. Temperature will reduce as a result if there is
anything in it that can "boil off". Basically, vacuum produces internal boiling of water and other things present in the material in the package. This will reduce temperature somewhat depending on the speed at which evacuation occurs and
hoe "deep" a vacuum is pulled. Chilling externally doesn’t cause a boil off of
substances in the package.
Vacuum is also a method of dehydration of food. A cup of coffee under strong vacuum will evaporate or boil off the water leaving the dry coffee behind. (Instant coffee) Vacuum just makes it happen a lot faster.
The principle behind refrigeration is the same. It depends on high pressure differentials in the closed system caused by pumping (compressing) refrigerant, and flash evaporation (decompressing).
