Method of packaging food using a liner

In a process for automatically packaging and covering, without use of heat, a chilled food product that partially fills the interior of a container, leaving the upper inner sidewall and uppermost rim portion of the container exposed to receive cover means thereonto, the improvement comprising the steps of:

• placing a sheet of flexible, but shape-sustaining material, having its support side coated with a pressure-sensitive adhesive, in overlying relation onto the uppermost rim portion of a container that is partially filled with a chilled food product, and then pressing a pre-formed outer cover member into the container and onto the uppermost rim portion of the container to force air from the container and to grippingly secure the outer cover to the rim portion of the container by a press fit while simultaneously flexing the sheet inwardly into the partially-filled container to pressure activate said pressure-sensitive adhesive and to pressure scrub a portion of said adhesive, as the sheet is flexed into the container, against both the uppermost rim portion and adjacent inner sidewall portions of the container, to effect a substantially continuous air-impervious adherent seal between the sheet and the portions of the container engaged by the sheet.