Abstract: A product such as ground meat is efficiently chilled in a blender device having an open top. Liquid carbon dioxide is introduced into the blender at a location below the surface of the product to thereby form solid and gaseous CO.sub.2. Mixing elements such as a ribbon screw or the like are operated to pass the product in a countercurrent relation to the carbon dioxide introduced into the blender thereby chilling the product and causing the resulting CO.sub.2 gas to rise along one wall of the blender. Deflector means are provided along such wall to direct the rising vapor toward an exhaust plenum located above the open top of the blender.