The invention relates to an identification system for insert elements for tempering food accommodated in containers. Advantageously, the invention can be used in particular for short-term, economic and high-quality heating of prefabricated food wherein heating can be preferably carried out in induction ovens. According to the object, the respective configuration and if possible also the equipment with containers of such an insert element shall be allowed to be recognized and taken into consideration for tempering. At the same time, the insert elements have definitely arranged containers which can be fixed in receiving means. An appropriately equipped insert element can be introduced into an induction oven or a cooling device wherein the containers of a horizontal plane are positioned at the same time. According to the invention, at least one electromagnetically or magnetically detectable element is mounted on the insert elements each in a predeterminable position. On the inner wall of an induction oven, in parallel with horizontal planes or with the horizontal planes of a cooling device, at least two detectors or detector units coupled with a control for induction coils or for the heat removal capacity of a cooling device are arranged for electrically, magnetically detectable elements.