Freeze-drying process

 

    

 

 

operating principle

 

    Freezing drying is a lot of moisture material, cool down into solid freeze in advance. And then in the vacuum conditions make steam sublimation directly, and material itself in the freezing left in the shelf. In order to increase the sublimation speed, shorten the drying time. Should be proper heating products, but the whole heating drying is carried out under the low temperature (heating dry in 0 ℃ below basically temperature, that is, in the state of frozen products until later, in order to further reduce product the residual moisture content, just make products to 0 ℃ above, but not the temperature of the general more than 50 ℃). 

Lyophilized characteristic

 

 1. Freezing drying in the low-temp, so for many of the thermal sensitive material apply. Such as protein, microbial and so on won't happen degeneration or lose biological energy, basic maintain the original shape, color and flavor and nutrition. 2. At low temperature drying, the matter of some of the volatile components little damage. 3. In freezing drying process, the growth of microorganism and the role of the enzyme can not, and therefore, can keep the original character. 4. Because of the state in freezing drying, so volume almost the same, keep the original structure, won't produce enrichment phenomenon. 5. After drying of porous material osteoporosis, a cavernous, add water dissolved after quickly and completely. Almost immediately restore the original character. 6. Because in the vacuum drying, very little oxygen, so some easy oxidation material are protected. 7. Dry can remove 95-more than 99% of the water, and the dry products can long-term preservation after without metamorphism.