Freeze drying, also known as lyophilization, is a food preservation method that removes moisture from food while preserving its structure, flavor, and nutritional content. The process involves three main steps:

Freezing: The food is frozen at very low temperatures, typically below -40°C (-40°F). Freezing solidifies the water content in the food.

Primary Drying: The frozen food is placed in a vacuum chamber, and the pressure is reduced. This causes the frozen water to sublimate directly from solid to vapor without passing through the liquid phase. Sublimation removes most of the moisture from the food.

Secondary Drying: In this final stage, any remaining bound water molecules are removed from the food using slightly higher temperatures. This ensures that the food is thoroughly dried and stable for long-term storage.

The result is lightweight, shelf-stable food and treats that retains its original texture, flavor, and nutritional value.