An apparatus for the heat treatment of a product, especially a food productsuch as a food product contained withina hermetically sealed container (11) or pouch of plastics or like material,for example for sterilisation, pasteurisation or cooking,which apparatus comprises: a heating unit (2) to bring product from ambienttowards a heat treatment temperature and pressure； aretort unit (3) to apply a heat treatment to a product； and a cooling unit (5)to allow product to be brought down from heat treatmenttemperature and pressure towards ambient； wherein each unit (45) and retort(3) is selectably sealable from the others and fromambient conditions； and wherein the retort (3) comprises a retort chamberenclosing a volume incorporating a plurality of mountingmeans (30) orbitally mounted about a longitudinal axis of the chamber so thateach mounting means (30) is movable at least betweena first position whereat it is aligned with an outlet of the heating unitwhereby product can be loaded into the mounting means, anda second position whereat it is aligned with an inlet to the cooling unitwhereby product can be unloaded from the mounting means(30)； one or more conveyors (40) to pass product through to the apparatus.
