China lab scale pilot vacuum freeze drying machine for freeze dried food processing craft research

What is Freeze dryer ？

Vacuum freeze drying technology is the most advanced technology for food dehydration processing at present. Compared with the common drying method, the freeze-dried food produced with this technology features long period of quality assurance, good re-hydration nature, good-looking color, good flavor, taste, shape and high content of nutritious components. The dried food basically remains unchanged in its volume and shape, it looks like sponge and has no shrinking. This kind drying technology can be widely used in process of vegetables, fruits, condiments, aquatic products, biological products, medicine, beverage and etc.

Advantages of Freeze Dried Food

1. Taste fresh. Freeze-dried foods, like frozen, retain virtually all their fresh-food taste and nutritional content. Freeze-drying removes the water, not the flavor.

2. Look fresh. Freeze-dried foods maintain their original shape and texture, unlike dehydrated foods, which shrink and shrivel due to high-temperature processing. Freeze-drying removes water under low temperatures which keeps intact the moisture channels and food fibers. Just add water, and in minutes every fresh food detail returns.

3. Weigh less than fresh. Freeze-dried foods have 98% of their water removed. This reduces the food's weight by about 90%. Because of its light weight per volume of reconstituted food, freeze-dried products are popular and convenient for hikers. More dried food can be carried per the same weight of wet food, and remains in good condition for longer than wet food, which tends to spoil quickly. Hikers reconstitute the food with water available at point of use.

4. Stay fresh. Freeze-dried foods can be stored at room temperature, without deterioration or spoilage. This is because freeze-drying and packaging remove both water and oxygen - the two primary causes of food deterioration.

5. Regain freshness quickly. Freeze-dried products can be rehydrated (reconstituted) much more quickly and easily because the freeze drying process leaves microscopic pores. The pores are created by the ice crystals that sublimate, leaving gaps or pores in their place.

6. Long-Term Storage. The freeze dried product in sealed packaging can be stored and transported at room temperature for a long time. Freeze-drying increase the shelf life of product for years.

Working Princple of Freeze Drying Machine

Under vacuum condition, material is freeze dried via principle of sublimation. The moisture in the pre-frozen material is directly sublimed from solid state (ice) to gaseous state (vapor), without melting. Freeze dried products are formed to be sponginess, without shrinkage and excellent in rehydration, containing little water only.