The advantages of Freeze Drying comparing with other drying methods
Principle of vacuum freeze-drying method:
It goes from liquid to solid to gas. During the freeze-drying process, the "liquid bridge" between the solute particles has been frozen into a "solid bridge", the relative positions between the particles have been fixed, and there is no surface tension between the particles at the gas-liquid interface. With the continuous sublimation of the solvent, the "solid bridge" decreases, but the relative position between the two particles no longer changes until the "solid bridge" completely disappears.
Advantages of Freeze Drying：
1. it is dried at low temperature, which does not denaturate proteins and make microorganisms and the like lose their biological vitality.
2. because of the low temperature drying, so that the volatile components in the material and by heat denaturation of nutrients and aromatic components loss is very small.
3. In the process of low-temperature drying, the growth of microorganisms and the action of enzymes can hardly be carried out, so zui can well maintain the original properties of substances.
4. After drying, the volume and shape are basically unchanged, and the compound water is good.
Because the general system under vacuum drying, oxygen is very little, so that easy to oxidize the material to be protected.
6 can remove 95-99.5% of the moisture in the material, the product storage period is long.
Vacuum Freeze Drying Application Area：
1 biological products, pharmaceuticals: such as antibiotics, antitoxins, diagnostic supplies and vaccine preservation.
2 Microorganisms and algae: long-term preservation of bacteria, yeast, enzymes, protozoa, microalgae, etc.
3. Biological specimens and biological tissues: such as making various animal and plant specimens, drying and preserving the marginal tissues such as skin, cornea, bone, aorta, heart valve and so on which are used for xenograft or homograft transplantation.
4 Make small tissue slices for optical microscopy, scanning electron microscopy and transmission microscopy.
5 Food drying: such as coffee, tea, meat, fish and eggs, seaweed, fruits, vegetables, spices, tofu, convenience food, etc.
6 Nutrients and herbs: royal jelly, honey, pollen, herbal preparations, etc.
7 preparation of ultrafine powders: such as Al2O3, ZrO2, TiO2, Ba2Cu3O7 ~ 8, Ba2Ti9O20 and other ultrafine powders.
8. Other aspects: such as catalysts in chemical industry, the catalytic efficiency can be increased by 5-20 times after freeze-drying; Plant leaves and soil were freeze-dried to study the effects of soil, fertilizer and climate on plant growth and the effects of growth factors. Damp wood
