Aflatoxin mainly exists in moldy grain, oil and peanuts. It is the metabolite of Aspergillus flavus and parasitic Aspergillus, which is extremely toxic and can cause liver cancer. As aflatoxin is a heat-stable chemical substance, it is not easy to be destroyed during cooking. Preventive measures are mainly mildew prevention. However, if the food is moldy and toxic, appropriate detoxification measures should be taken: for example, peanut can be eliminated by mildew; Rice can be rolled and rubbed with water; Vegetable oil can be detoxified by adding alkali and so on.