What is the difference between dehydrated and freeze dried foods?

Dehydrating food is simply having the water content removed through low heat, modern air drying methods. During dehydration, the product shrinks making it up to 80% less bulky than normal, and up to 75% lighter in weight. Freeze drying involves removing moisture through a space age freeze blasting method, then “super heating” it to cause all the water to vaporize into steam. Freeze dried food does not shrink in size and keeps the original volume, thus requiring more storage space. In terms of nutritional value, there is simply no difference between the two methods. However, for food storage, low-heat dehydration is preferable since it shrinks the size of the food allowing you to store more food in less space.