Knowledges of Freeze Dry

Fundamental:

Lyophilization or freeze drying is a low temperature dehydration method, the fundamental principle of freeze drying is sublimation. The process begins with freezing raw material to its freezing point or below, move to a chamber and creat vacuum environment, proper add heat to chamber enable the frozen water sublimate to vapor.

Working Process:

Freezing stage: Raw product thoroughly freezing, can be done inside a freeze dryer lyophilizer or in external freezer.

Primary drying stage: Frozen product placed in drying chamber, vacuum environment is created and sublimation starts. > 95% physical water was removed.

Secondary drying stage: Higher shelf temp. and extreme vacuum environment is created to remove the bound water. <3% water remaining after drying finish.