The present invention relates to a method, means and packaging system to preserve nutritious values of food included in a food dish. The invention is characterized in that the food ingredients are placed in a tempered storing container forming part of a storing system including a container (A) with a lid part (B), whereby the lid part has a chamber (C) for receiving of a phase exchangeable medium, and which chamber (C) is restricted of an inner covering part (E) which is sealed and attached to the lid part (B) by a joining means (F) at the same time forming a seal between the storing container and lid part, that the phase exchangeable medium is cools/heated during a phase exchange to a solid/liquid state and is placed on the storing container to cool/keeping warm/heating the food.