How Are Freeze Dried Meals Made and Processed?

Preparation and Freezing

Freeze-dried meals are typically prepared by cooking the ingredients in large batches. This can include meats, vegetables, and seasonings. The cooked ingredients are then portioned out into individual servings and frozen in a process called “blanching,” which helps preserve the nutrients and texture. For example, a batch of freeze-dried chili might be prepared in a 20-quart kettle, cooked to an internal temperature of 160°F, and then portioned out into 1-cup servings.

Freeze-Drying Process

The frozen ingredients are then placed in a vacuum chamber, where the water content is removed through a process called “sublimation.” This occurs when the frozen water turns directly into a gas, without going through the liquid phase, resulting in a dry, powder-like consistency. The freeze-drying process typically takes 8-12 hours to complete, depending on the equipment and the size of the batch. For example, a commercial freeze dryer might be able to process 10-20 pounds of food per hour.

Packaging and Quality Control

Once the freeze-dried ingredients are removed from the vacuum chamber, they are packaged in airtight containers or bags to preserve their texture and flavor. Before packaging, the ingredients may be rehydrated to test their texture and flavor. This is called “reconstitution testing.” The finished product is then inspected for quality and packaged for distribution. Freeze-dried meals can be stored for up to 25 years or more if properly packaged and stored in a cool, dry place.