Abstract: An air treatment plant comprises a housing (1); a conveyor (4) adapted to feed food to be processed through an inlet opening (2) in the housing, to and through an air treatment area, and to feed the processed food from this area to and through an outlet opening (3) in the housing; a heat exchanger; and a circulation fan for generating a circulating air flow through the heat exchanger, the air treatment area, and the circulation fan in succession. A pressure regulating fan (25) is connected to a chamber (33) adjacent to one of the inlet and outlet openings (2, 3) for generating a pressure difference across that opening substantially equal to that across the other opening, thus minimizing the air exchange between the interior and the exterior of the housing (1). The conveyor (4) inwardly of this one opening passes a tunnel with at least two air curtain ducts which are directed substantially transversely of the conveyor path and through which some of the circulating air flows.

Abstract: A pelletizer for making pellets from a liquid or semi-liquid food product has two molding rolls between which the food product is formed into pellets. The rolls have teeth of complementary shape, and the teeth of at least one roll have axially spaced apart recesses. The rolls are cooled with a refrigerant during the molding operation. By the means of the pelletizer, frozen pellets are made from a liquid or semi-liquid food product which, prior to molding, is refrigerated into moldable consistency before being supplied to the nip between the two cooperating molding rolls which are cooled during the molding operation so as to form surface-frozen pellets which are thereafter subjected to final freezing.

Abstract: In an air treatment plant, an endless conveyor belt travels in a helical path over a part of its length. The conveyor belt comprises a bottom consisting of transverse rods and a wire netting, and side plates fixedly connected in pairs with two rods so as to form, together with these rods, a link, which is movable relative to adjoining links about two axes perpendicular to the longitudinal direction of the belt and situated one in the plane of the bottom and the other perpendicular thereto. The wire netting consists of zig-zag wires, each of which encloses not only the two rods of one link but also one adjacent rod of the adjoining link. Furthermore, the ends of each wire are fixed to one of the two rods of the associated link.