The so-called irradiated food is the sterilized food irradiated by gamma rays (cobalt source) or electron beams, and the purpose of irradiation is to meet the food hygiene standards. The principle of irradiation is that the interaction between rays and matter is mainly ionization. Because the radiation energy used in irradiation is low, nuclear reaction will not occur, that is, radioactivity will not be induced, so there is no radiation residual pollution. The name of nuclear contaminated food implies that it is nuclear contaminated food and is radioactive.