Abstract: An air treatment plant for foodstuffs includes an elongate trough (29) for the foodstuffs, a heat exchanger (35), a fan assembly (39) for circulating air on a path through the heat exchanger, through the trough, and back through the heat exchanger, a housing (1) having a housing bottom (7), and side walls (2, 3) with modular units (11) extending transversely to the trough. Each one of the modular unite includes an insulation layer (19), a water-impermeable inner layer (20), and two submodules (12, 13). Each has a respective submodule bottom with a respective bottom panel (15, 16) and a side-wall panel (17, 18) forming part of side walls (2, 3). One or more elongate, separate second bottom panels (14) interconnect the first bottom panels (15, 16) of the two submodules. Upper sides of the bottom panels (15, 16) of the submodules slope downwards toward at least one of the second bottom panels (14).

Abstract: A method and arrangement for enforced heat transmission between a solid or liquid alimentary body and an ambient gas takes place in connection with cooling/freezing or when cooking, frying or drying the entire part or parts of the alimentary body. This method and arrangement uses a low-frequency standing sound wave. The apparatus uses a low-frequency sound generator having a pulsator part and a resonator part. The resonator part is acoustically virtually closed and is designed so that the alimentary body, which is to be exposed to enforced heat transmission, is located within a zone inside the resonator part where the standing sound wave has a particle velocity anti-node.

Abstract: In a method for preventing bacterial growth in a refrigerating or freezing plant for food, the plant (1 ) includes a substantially closed housing (2) and, arranged therein, a device (3) for refrigerating food in this housing, and has an operating cycle including a work period during which the refrigerating device (3) is active, and a rest period during which the refrigerating device (3) is inactive and the plant can be cleaned. The cleaning includes raising the temperature in the plant above a temperature requisite for killing bacteria. Furthermore, the air pressure in the plant is maintained higher than the ambient pressure, at least during the entire rest period, by supplying air free from bacteria. The plant (1) includes heaters for raising the temperature therein during a rest period above a temperature requisite for killing bacteria, and air supply devices (7, 8) for supplying the air free from bacteria.

Abstract: An apparatus for freezing of food products comprises an insulated housing, an endless, foraminous conveyor belt following a helical path for forming a belt pile having several tiers in the housing, and helical rail means for supporting the conveyor belt at one side thereof along the helical path. Cooled air is circulated through the belt pile. Nozzles for ejecting cooled, pressurized air are positioned between the tiers of the belt pile, such that a plurality of air jets are ejected from the nozzles for impinging upon both a top side and a bottom side of food products carried by the conveyor belt past the nozzles.

Abstract: An endless conveyor belt of a belt conveyor system in a plant for air treatment of food products follows a helical path section preceded by a straight path section and followed by another straight path section. In the preceding straight path section, the conveyor belt remains collapsed and in the following straight path section, the conveyor belt remains expanded. At the transition between the preceding straight path section and the helical path section, the conveyor belt is expanded along the outer lateral edge of the belt. At the transition between the helical path section and the following straight path section, the conveyor belt is expanded along the inner lateral edge of the belt.

Abstract: In a method for freezing the surface of one of a food product, the product is placed on a supporting structure (1). This has previously been given such a low temperature that the product when contacting the supporting structure will not freeze on to it. The product is maintained on the supporting structure for a sufficient time to cause at least its surface layer nearest the supporting structure to pass into the frozen state. An arrangement for carrying out the method comprises, in addition to the supporting structure, also means for imparting to it the low temperature, such as means (2-4) for supplying a cooling agent to the underside of the supporting structure.