Abstract: A semi-rigid, deflectable reusable lid in the shape of a disk and formed of a non-porous material is adapted to hermetically seal the open mouth of a container. The lid is positioned over the mouth of the container to be sealed and is retained in position by a threaded band. The inner lid surface adjacent the perimeter of the lid is elastomeric or pliable and is adapted to be depressed by the rim of the container during the cooling interval of the usual food processing cycle to provide a seal between the inner surface of the lid and the rim of the container. When the container is sealed, the central portion of the lid is drawn partially inwardly into the open mouth by the reduced pressure within the container. The lid may be formed of one or more types of suitable material to achieve the deflectable and sealing characteristics desired.