are delivered to the device in one of the embodiments depicted by means of conveyor 4 through the window 17 the food conveyor 19 consists of a channel of u shaped cross sections with sides and a mesh or perforated bottom which permits an upward flow of air therethrough from the passageway 20 adjacent the refrigeration coil 2 this upward flow of air causes a slight elevation in the food particles which are introduced from the conveyor 4 to produce a fluidized bed the force of newly delivered food through the window 17 is sufficient to propel the food particles in their fluidized state along the trough 19 until they reach the terminous thereof at which point they are removed from the unit a small swinging door is provided at the terminous of the trough 19 to cause the food particles to back up to a predetermined depth behind it thus this swinging door which may be spring loaded functions as a weir in the fluidized bed it will be appreciated that this embodiment of the present invention functions by directing a stream of air from the fans or blowers 6 through the passageway 18 and across the cooling coils 2 into the passage 20 from which the blast of refrigerated air proceeds upward through the bottom.