Details of the vessel... Preservation of the fish... Air blast freezing... Plate freezing...
Plate freezing is another common freezing method used in the seafood industry. However, it can only be used to freeze products or packages of the same size and shape. Plate freezing is carried out between hollow metal plates that have a liquid or gas refrigerant circulating through them, which makes them very cold. The plates are arranged either horizontally or vertically and connected within a cabinet. When cartons of product are placed between the plates, the plates move together so that they are in close contact with both the upper and lower sides of the carton (without squashing it).
This close contact with the very cold plates (-30°C to -40°C) means that freezing can be very fast.