Control Moisture Content of Freeze Dried Products

Moisture content is the core quality index for freeze-dried products processed by freeze dryer. If moisture content of freeze-dried goods is too high, products are easy to absorb moisture from air, breed microorganism and go bad during storage. If operators over-dry materials on food freeze dryer to get ultra-low moisture, freeze drying time will be greatly extended and energy cost increases sharply. Vacuum freeze drying equipment removes bound water inside material in the later desorption drying phase. Technicians set target moisture value according to different product standards. While fruit and vegetable freeze dryer works, sampling test is required to monitor moisture change. After batch production, quality inspectors take samples from freeze drying production line and test moisture content. Products exceeding standard moisture will be separated and reprocessed if possible.