What are the freezing processes in freeze-drying machines?

Immersion Method: The raw materials are immersed in substances such as liquid nitrogen, liquid Freon, and ultra-low-temperature brine to achieve rapid freezing and preservation. This method offers a faster freezing rate.

The Air-Cooled Method: Blowing super-low-temperature cold air onto raw materials to freeze them to a certain temperature within the required time.

Direct Cooling Method: Placing the refrigerant or coolant inside the evaporation piping to absorb the heat generated by the raw materials, achieving the cooling purpose.

Vacuum Pump Cooling Method: Utilizes vacuum packaging to vaporize moisture from raw materials, thereby removing heat. This method achieves the cooling of raw materials for refrigeration purposes.

Regardless of the method used, it should be ensured that the raw materials are frozen to a certain temperature within the required time, under the premise that the base does not deform.