In 1986, the movie Space Camp was released and freeze-dried ice cream became all the rage around the country. These small packages of impossibly light and dry Neapolitan ice cream were everywhere. For many of us, this unusual, crunchy confection was our first introduction to freeze-dried food. Freeze-dried ingredients were originally popular with the military and NASA, and later gained a foothold with camping outfitters as an extremely lightweight way to carry a variety of foods into the wilderness that could be easily prepared with the simple additions of water and heat. These products are known for retaining the texture and flavor of the original ingredients. Freeze-dried foods also have the double advantage of retaining the majority of their nutrients and being resistant to spoilage due to their inherent lack of moisture.
Freeze-drying or lyophilization is used to maintain the composition and structure of whatever is being frozen by avoiding the use of heat to evaporate liquid. The freeze-drying process converts the solid, frozen water directly to vapor and allows it to evaporate out of the product during the drying process.