I ordered the sandwiches from Freeze Drying Concepts, if by chance you want to order the same ones.
To save you some trouble:
- Basically, freeze drying works by increasing the temperature from below 32 to above 32 degrees Fahrenheit and decreasing the pressure at the same time.
- Water will sublime (have enough energy to escape its frozen state) if the temperature is "high" enough (when compared to freezing or below) and the pressure is "low" enough.
- The water molecules can escape, because they will have enough energy from the higher temperature to become gaseous, yet they will not be confined to a liquid form due to the low pressure.
Here's a cool diagram and a quote from HowStuffWorks.com:
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"...if you increase the temperature above 32 F while keeping the atmospheric pressure below .06 atmospheres (ATM), the water is warm enough to thaw, but there isn't enough pressure for a liquid to form. It becomes a gas."