Freeze and Seal

• The freeze-drying process starts with a rapid freeze that turns the moisture inside foods to ice. With the help of low heat and a specially designed vacuum, the ice is immediately turned to vapor by sublimation -- a physical change that turns solids to gases, bypassing the liquid phase. With approximately 90 to 98 percent of the food's moisture removed, the remaining product is then enclosed in a hermetically sealed wrapping to ensure quality during storage.

The Freeze-Dry Advantage

• Removing the water content of a food through freeze-drying reduces its overall weight, resulting in a lighter, more compact product. The process also locks in the flavor, freshness and nutritional value of these foods during storage. Unlike the recognizable shrinking and shriveling associated with other preservation methods, the shape and texture of freeze-dried foods remain unaffected, with fibrous structures and valuable moisture channels remaining in place during and after the process.

Out of the Fridge

• The airtight, moisture-proof packaging that envelops freeze-dried food products maintains quality at room temperature, so there is no need to refrigerate. Average room temperature is between 68 and 77 degrees Fahrenheit, well above refrigerator and freezer temperatures of 40 F and below. Since air and moisture are not factors for the sealed, freeze-dried product, you don't have to worry about bacterial spoilage or deterioration. Once the seal is broken, though, refrigerate the product, as these risks are once again relevant.

Easy Rehydration

• Since the food’s moisture channels are still intact after freeze-drying, all it takes is water to rehydrate it. The porous nature of the freeze-dried product allows the water to enter the food and regain its natural position within the molecular arrangement. Once the sublimated water is replaced, the food reverts back to its pre-processed appearance, complete with the original fresh flavors and aromas. The amount of water necessary to rehydrate varies from product to product.