A support tray 6a with a product 11a thereon is covered loosely by a cover sheet 8 in a first chamber portion 12 to be drawn upwardly into contact with the heated walls of a shallow first mould cavity. The combination of the product 11a, support tray 6a and cover sheet 8 is then advanced to a second chamber portion 13 defined by a deeper second mould cavity into which the cover sheet can be drawn while vacuum is applied to the interior of the ensuing pack through slits in the tray 6a, by means of suction ports 20. |