A mains electricity (AC-powered) appliance intended to be used to rapidly freeze bags containing plasma or other biological specimens to a core temperature of -30° Celsius (-22° Fahrenheit). It typically consists of a single or multiple shelves with adjustable contact plates, between which the bags are placed for freezing. It is not intended for storage; frozen bags are subsequently transferred to an appropriate storage freezer. It has sensors, controls, and monitors to display freezing progress (time/temperature graphs). It may include associated software for documentation of data and tracing of the bags.