PURPOSE: To shorten the cooling time without deforming the vessel and prevent pollution of the contents by providing a vessel which when used is designed to be stoppered immediately after filling with food or the like and which has a built-in filter permitting the permeation of air to and from the vessel in accordance with changes in pressure during heating and cooling in the pasteurizer and by so doing to eliminate dust and germ.

CONSTITUTION: A plastic stopping cap 3 having a built-in filter 5 is attached to the top of a vessel 1 and air holes 4 are formed under the stopping cap 3. Urethane sponge is used for the filter 5 to give it permeability to air. When the pressure is reduced during heating by a retort and vacuum cooling, the gas emitted from food or the like contained inside the vessel 1 flows into the retort through the filter 5 and, when the pressure is recovered following completion of the cooling, air is drawn into the vessel through the filter 5 from the outside. The filter 5 eliminates dust and germ from the air when air is thus drawn in. With increase and decrease in the pressure in the retort, the food or the like contained in the vessel with the stopping cap is heated and cooled rapidly; the vacuum cooling is carried out rapidly and smoothly without involving deformation or breakage of the vessel.