Product category：Vacuum Freeze Dryer
HXD series food freezing dryer is developed by our company together with some national research institutions, with customized models, top technology, high configurations to make perfect conbination of aseptic technique and freezing drying technique. It can be maximum applied in big scale production and solve confliting between output and selling in agricultural peak period, also advance original ecology storage technology for agriculture products and increase both production and income.
Vacuum freezing dryer is composed of vacuum drying system, refrigeration system, heating system, heating plates, gauges and control system, etc. Suitable for freezing drying process of aquatic products, vegetables & fruits, meat, mushrooms, etc.
Drying for biology technology, aquatic products, grain, fruits, foods, milk, medicine, etc. It is suitable for produts which sensitive about temprature, easy get bad, but needing its original taste kept and no destroy on structure.
Four basic conditions during freezing drying process:
1. Surface temperature of cold trap lower than -35℃
2. Product is below freezing point.
3. Vacuum degre ⩽40Pa
4. Production temperature is controlled between -40℃~+60℃ with sublimation potention heat, and products not melt above eutectic point.
a. Pre-freezing; b. Initial drying; c. Main drying; d. reduce drying; e. ultimate drying.
a. Product water rate in best economical principle is between 60~90%, tray loading thickness at 10~15mm.
b. Pre-freezing can be in machine or cold room;
c. Heating plate must control product temperature at 5~10℃ below eutectic point during main drying period and no melting, maximize temperature difference with cold trap to speed up drying rate.
d. Heating plate temperature in ultimate drying stage would be product highest temperature without spoilage.
Freezing drying is to blast freezing products to be solid form, then sublimate ice to be vapor in high vacuum environment to remove product’s water. Advantages are as follows:
u Product water rate can be lower to 1~3% around to be with good saving condition, no change on volume, foam splitting, surface hardening and structure. The product color, flavor, taste and original ingredient can be well kept.
u Best dehydration method with betst rehydration performance, other dehydration method can’t reach such performance.
u Operatoin is under lowe temperature and closed vacuum environment which prevent products from oxidation and contamination.