Freeze-drying is different from traditional drying methods. The product is basically dried at a temperature below 0℃, that is, in the frozen state of the product. Until the later stage, in order to further reduce the residual moisture of the product, the product was heated to above 0℃, but generally not more than 40℃. Freeze-drying technology will not lose the nutritional components of food, such as protein and microorganisms, and will not denature or lose its biological activity.
After freeze-drying, the solid matter has a porous structure, maintains the volume when frozen, and is easy to dissolve and recover after adding water. Soaking in warm water for one minute can restore the freshness of food by more than 80%, which not only perfectly retains the appearance, but also rarely retains most nutrients and flavor. In food processing, freeze-drying technology fully embodies the perfect preservation of "body" and "soul".
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Advantages of freeze-dried food
1, high nutrition: vacuum freeze-drying processing is carried out at extremely low temperature and high vacuum degree. In the process of processing, the food is basically in an oxygen-free and completely dark environment, with little thermal denaturation, which effectively maintains the color, fragrance, taste and shape of fresh food, and maximally preserves various nutrients and flavor substances such as vitamins, carbohydrates and protein in food.
2. Tastability: Because the moisture in food will be precipitated in situ during freeze-drying, this avoids the undesirable phenomena of food nutrition loss and surface hardening caused by the flow and migration of moisture inside food to its surface in general drying methods.
After dehydration, fresh vegetables and fruits taste more sweet and delicious than before because of the concentrated fragrance and sugar. The dehydrated fresh meat tastes better than before, improves palatability and has good rehydration effect.
3. Ultra-long storage, easy to use: freeze-dried food is completely dehydrated, light in weight, very convenient to use or carry, and most of the freeze-dried pet food is packaged in vacuum or nitrogen, and stored away from light. The shelf life of this sealed package can be as long as 3 ~ 5 years or even longer at room temperature.
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