Air-activated type food self-heating composition, and preparation method and application thereof

The invention discloses an air-activated type food self-heating composition, and a preparation method and application thereof. The self-heating composition comprises the following effective compositions: a zinc powder, active carbon, an electrolyte and a catalyst. A self heating device prepared by employing the self-heating composition does not need water as an activator, is convenient to use, begins to release heat when a packaging bag is torn, and can started at various operational environments with the temperature of -30 DEG C or more. An air activating manner is employed, and the temperature of the self heating device reaches 80 DEG C or more within 60 s, and the time of the product maintaining 80 DEG C or more is not less than 10 min. The ratio of the food net content to the weight of the self heating device is not lower than 5:1. No toxic and combustible gases are generated during heating, and hydrogen and water vapor are not generated in the heat release process, and the safety and the crypticity are both good. The product does not generate obvious smell, does not need water during usage, is clean, and does not generate any pollutants on the food packaging bag.