Freeze drying is a process to dehydrate products by freezing products and then reducing the pressure to make the frozen water content in the products sublime.
This way does not damage the product structure like other dehydration processes which require high temperature. Hence, the products have dry and solid outer surface and light weight enabling easy transportation and storage.
Freeze dried products can quickly recover their original shape in water. They also have the closest shape, color, taste, texture and nutritive value to that of the fresh products.