Freeze Dried dairy products
Compared with other drying methods, freeze-dried foods have many advantages, mainly including:
(1) The color, aroma and taste of food shall be preserved to the maximum extent. For example, the natural pigment of vegetables shall remain unchanged, and the loss of various aromatic substances can be reduced to the minimum; Freeze drying is better than ordinary freezing preservation for the preservation of food containing protein.
(2) It is particularly suitable for heat sensitive materials, which can keep the heat sensitive components after drying the heat sensitive materials; It can preserve all levels of nutrients in food, especially vitamin C, which can save more than 90%.
(3) Under vacuum and low temperature, the growth of microorganisms and enzyme action are inhibited.
Complete dehydration, light weight and small volume of dry products, small floor area during storage and convenient transportation; The weight of various freeze-dried vegetables was significantly reduced by pressing. Due to the reduced volume, the packaging cost is correspondingly much less.
Quick rehydration and easy to eat. Because the moisture contained in the dried materials is directly evaporated in the frozen state, during the drying process, the water vapor will not drive the soluble substances to move to the material surface, and will not deposit salts on the material surface, that is, no hard thin skin will be formed on the material surface, nor will there be tension on the cells or fibers when the central water moves to the material surface, and the material will not be deformed due to shrinkage after drying, so it is very easy to absorb water and recover to its original state.
Due to the operation under vacuum, there is very little oxygen, so some easily oxidized substances (such as grease) are protected.
The freeze-drying method can remove more than 95% ~ 99% moisture, and the product can be stored for a long time without deterioration.
