Method for providing a heat treated filled and closed can, including the consecutive steps of: filling a metal cup, closing the metal cup with a lid making a gas tight heat treatable can, heat treating the can, wherein measures are taken to achieve an under-pressure in the can after closing the cup and wherein the can is chosen that is either of a flexible type on the one hand or of a rigid type with increased strength provided with a seal on lid on the other hand. The measures comprise a step belonging to the group of steps consisting of: using a partly frozen filling; having the filling include constituents that interact after closing so as to lower the specific volume of the filling in the can; adding steam to the cup after filling and before closing; closing the cup under sub-atmospheric pressure; and partly evacuating the can after closing.