Method of apparatus for canning food products

Claim 1

Apparatus for canning food products, comprising a container having a removable lid capable of forming an air-tight seal against the open upper extremity of said container under the influence of a lower than ambient pressure within said container; a pressure cover for covering the upper portions of said container and including pressure sealing means for forming a pressure-tight engagement with portions of the sides of said container, whereby the combination of the pressure cover and the container so covered forms a completely enclosed pressure vessel; means for resiliently urging said container lid downwardly against said upper extremity of said container; pressure control means for limiting the maximum pressure differential between ambient and the pressure within said combined pressure cover and container to a predetermined level; a base member; and means for releasably connecting and restraining movement of said pressure cover relative to said base member, whereby a container and lid enclosing a food product, positioned and held by the base, may be engaged by the pressure cover and its sealing means when heat is applied from a heating unit to the containers, with the cover connected to the base assembly, for limiting pressure within the combined container and cover to the predetermined level to sterilize the food product, with subsequent cooling of the container causing the pressure within the container to be less than ambient to effect an air-tight seal between the lid and the container upper extremity.