Secrets about freeze dried food

Freeze-dried foods are extremely popular among culinary masters, climbers, soldiers, explorers, hunters, hikers, backpackers, and all sorts of other people. However, there are a few things that people do not know about freeze-dried food. Firstly, freeze-dried food is made by using the freeze-drying or so-called lyophilization method. At the beginning of the lyophilization, the temperature of the food is lowered below freezing, and then the pressure is applied to force the water in the food to freeze and form ice crystals. These ice crystals then undergo the process of sublimation. Sublimation is the process in which a substance transitions from a solid to a gas state without passing through the liquid phase. In other words, in the sublimation process, the water from the food product is extracted in the form of vapor. The sublimation process allows reducing the moisture content in the food up to 98-99%. After the sublimation of ice into vapor without an intervening liquid state, freeze-dried foods have a porous structure. When adding hot or cold water and waiting for a few minutes, freeze-dried food can be prepared easily and quickly because moisture can efficiently fill those pores and rehydrate the food in its original form. Therefore, the freeze-drying process removes the water, but not the valuable nutrients and fiber. In other words, freeze-dried food retains the nutrition, flavor, aroma, and texture of raw or fresh products. Due to the lower volume and weight of the food after freeze-drying, freeze-dried foods can be transported and imported in a much more convenient and eco-friendly way. Finally, the freeze-drying process allows extending the shelf-life of the food for years and even decades while maintaining the quality.