Abstract: A refrigeration device (10) including a generally cylindrical tank (11) including outer sidewalls (14) adapted to contain a first fluid. The device further includes a heat exchange fluid inlet (17) to the tank, a heat exchange fluid outlet (18) from the tank and a refrigeration unit (60). At least one hollow refrigeration evaporator coil (19, 20) is in fluid communication with the refrigeration unit by means of refrigerant feed and extraction pipes (61 and 62). The coil is helically disposed within the tank for freezing the first fluid adjacent the coil, such that in use the frozen fluid and the sidewalls together define a substantially helical path to direct the flow of a heat exchange fluid from the inlet to the outlet.