The difference between the freeze-dried and drying, which good?
Freeze-dried vendors would come together to discuss below:
1, freeze-dried and drying the working principle of the difference between the
freeze-dried is the sublimation of moisture, drying is the evaporation of the water, the former is solid directly into a gas, the liquid to gas.
the lyophilizer is a vacuum low temperature drying equipment, first the moisture in the material at low temperature frozen into ice, then rapid heating in vacuum environment, make the sublimate directly without liquid water, finally complete the purpose of dehydration.
also known as thermal drying, drying is the use of heat carrier and drying process of wet carrier to cooperate to complete each other, usually in the hot air and heat and wet the carrier, is heated air air heating samples again, evaporated water sample was taken away by air out side by side again.
2, freeze-dried and drying the nutritional difference between
the process of freeze-drying processing can be seen as the principle of physical sublimation.
For maximum keep the physical structure of the sample, so far the best way is the low temperature freeze-drying, because in the condition of low temperature low pressure, the physical structure of the basic sample are not affected.
Will not happen because the humidity of inside and outside the cell wall exist gradient and seepage surface pores or internal water loss leads to dry.
And in the low pressure vacuum enable higher sublimation point (
Tend to room temperature)
。
To speed up the sublimation process, improve the efficiency of drying.
lyophilizer compared with drying technology, the freeze-drying technology can be food nutrients such as color, aroma and taste of the preserved as much as possible, and effectively extend the shelf life.
outside-in drying is the function of sample temperature, humidity by outside introversion (
On the contrary)
。
And there's a speed limit, the sample is in can withstand the limit temperature.
The maximum speed of internal diffusion moisture to appearance.
Speed will cause skin shrinkage, reduce the drying speed, slowly influence efficiency.
High temperature can cause the internal moisture vaporizing too fast at the same time, not through capillary discharge and inflation, cause cell rupture.
drying way because of the high temperature drying, can lead to material shrinkage deformation, nutrient loss greatly.
