The present invention relates to a method of cooking and/or pasteurizing foodstuff in a container, the method comprising the following steps, providing a sealed container comprising foodstuff, placing said sealed container in a cooking unit, cooking and/or pasteurizing said foodstuff by applying heat or microwaves to said sealed container, wherein an external force is provided to said sealed container during at least a part of the step of cooking and/or pasteurizing said foodstuff in order to limit expansion of said sealed container.The present invention also relates to a deformation control device, a kit comprising a deformation control device and a container, as well as the use of a deformation control device in a method of cooking and/or pasteurizing foodstuff in a container.
