A self-heating MRE (Meal, Ready-to-Eat) is a type of MRE that includes a self-contained heating system (FRH) to warm the food without the need for an external heat source. Self-heating MREs typically use a chemical reaction to generate heat and warm the food.
The self-heating system in an MRE typically consists of an FRH - Flameless Ration Heater, which is a packet containing a combination of aluminium, iron, and salt. When water (or an Activation Sachet for a stronger reaction) is added to the packet, the chemical reaction between these elements generates heat, which warms the food inside the MRE pouch.
To use a self-heating MRE, you would typically tear open the MRE pouch, remove the flameless ration heater, and add a small amount of water to the packet. Then you would place the MRE pouch and the flameless ration heater back into the outer pouch and wait for the chemical reaction to heat up the food. This process usually takes around 10-15 minutes. Self-heating MREs are popular with military personnel, hikers, campers, and other outdoor enthusiasts, as well as emergency responders and disaster relief organizations, because they provide a convenient and reliable source of hot food in situations where traditional cooking methods may not be available.