Self-heating food packaging
Self-heating food packaging (SHFP) is active packaging with the ability to heat food contents without external heat sources or power. Packets typically use an exothermic chemical reaction. Packets can also be self-cooling. These packages are useful for military operations, during natural disasters, or whenever conventional cooking is not available. These packages are often used to prepare main courses such as meat dishes, which are more palatable when hot.
Commercial heat sources for self-heating food packaging use an exothermic (heat releasing) reaction between quicklime, or calcium oxide, and water. Quicklime, inexpensive and readily available, is generally recognized by the FDA as safe. The product of the reaction is calcium hydroxide.