What are the advantages of freeze-dried food?
Due to the production under low temperature and low pressure conditions, the decomposition or oxidation of certain ingredients in the food material is prevented, and the harmful effects of microorganisms and enzymes are inhibited, thereby maintaining the freshness and nutritional content of freeze-dried food.
During the sublimation process, water is gradually removed from the surface to the inside in the molecular state, without destroying the tissue structure of the food, without taking away natural pigments and aromatic substances, so the shape, color and taste of freeze-dried food are almost the same as fresh food. .
During the sublimation process, the ice crystals in the food form micropores like sponges, so after immersing the freeze-dried food in water, it can quickly absorb water and recover, just like fresh products.
Since it has been washed and cut and rehydrated very quickly, it is extremely convenient to eat or cook directly.
Freeze-dried food?
Almost all foods with water can be freeze-dried, but some foods with high sugar or gum content and foods with too low eutectic point temperature are relatively difficult to freeze-dry.
Various types of foods that can be freeze-dried, such as the following:
○ Vegetables: chives, carrots, garlic, onions, ginger, peppers, yam, spinach, cauliflower, green beans, edible fungi, etc.
○ Fruits: apples, peaches, pears, apricots, red dates, strawberries, bananas, pineapples, cantaloupe, etc.
○ Meat: beef, mutton, pork, chicken, snake meat, turtle, etc.
○ Aquatic products: fish fillets, shrimps, crab meat, cuttlefish shreds, whitebait, etc.
○ Convenience food: instant noodle accessories, beef noodle accessories, meatballs, soup, pet feed, etc.
○ Instant beverages: coffee, milk, soy milk, fruit juice, royal jelly, etc.
○ Condiments: all kinds of cooking condiments.
○ Medicines: deer antler, deer blood, earthworms, scorpions, turtles, ginseng, Codonopsis, angelica, rhubarb, various health foods, etc.
How is food freeze-dried?
Water absorbs heat and can become steam, and ice absorbs heat can also become steam. The former is called evaporation, and the latter is called sublimation. Drying is evaporative dehydration; freeze-drying is sublimation dehydration. After the water-containing food is quick-frozen, under vacuum and proper heating conditions, the water in the food can be sublimated and removed, thereby obtaining freeze-dried food.
Do different freeze-dried foods use the same sublimation process?
Due to different materials, different shapes after pre- and post-processing, different moisture content, and different loading amounts, the sublimation process used will naturally not be the same. In order to obtain a better sublimation process, a small experimental machine is generally used for experiments and then put into production.