It is widely used biological products, chemical and food industries. It is very suitable for freeze-drying technology of heat-sensitive substances such as antibiotics, vaccines, blood products, enzymes, hormones and other biological tissues. Vacuum freeze dryers are widely used in medicine, pharmaceuticals, biological research, chemical industry and food and other fields. Freeze-dried items are easy to store for a long time and can be restored to their pre-freeze-drying state after adding water and maintain their original biochemical properties.