Cryopreservation:The process of preserving biological materials, such as cells, tissues, or organisms, by cooling them to very low temperatures, typically using liquid nitrogen at -320°F (-196°C).
Freeze-Drying: A dehydration process that involves freezing the material and then reducing the surrounding pressure to allow the frozen water in the material to sublimate directly from the solid phase to the gas phase.
Ice Nucleation: The initial process of ice crystal formation, which can be influenced by various factors, including the presence of foreign particles or impurities, and can affect the effectiveness of freezing in controlling microorganisms.