Freeze drying is the process of dehydrating frozen foods under a vacuum so the moisture content changes directly from a solid to a gaseous form without having to undergo the intermediate liquid state through sublimation. In this process, the product maintains its original size and shape with a minimum of cell rupture. Removing moisture prevents a product from deteriorating at room temperature.
The process is used for drying and preserving a number of food products.
The dried product will be the same size and shape as the original frozen material and will be found to have excellent stability. Freeze dried products will maintain nutrients, color, flavor, and texture often indistinguishable from the original product.
Depending on the product and the packaging environment, freeze dried foods are shelf-stable at room temperature for up to twenty-five years or more.
The Benefits of Freeze Drying:
- Retains original characteristics of the product, including:
- Nutrients
- Color
- Form
- Size
- Taste
- Texture
- Shelf stable at room temperature – cold storage not required
- The weight of the freeze dried products is reduced by 66-90 percent, depending on the product being dried, with no change in volume.
- Offers highest quality in a dry product compared to other drying methods
- Virtually any type of food or ingredient, whether solid or liquid, can be freeze-dried
- Low water activity virtually eliminate microbiological concerns