Food additives as an auxiliary ingredient can directly or indirectly become food ingredients, but can not affect the characteristics of foods. They are substances that do not contain pollutants and are not intended to improve food nutrition. China's "Sanitary Standards for the Use of Food Additives" divides them into 22 categories: preservatives, antioxidants, coloring agents, bleaches, sour agents, coagulants, bulking agents, thickeners, defoamers, sweeteners, Coloring agents, emulsifiers, quality improvers, anti-caking agents, flavor enhancers, enzyme preparations, coating agents, foaming agents, preservatives, perfumes, nutritional supplements, and other additives.

In order to ensure the correct use of food additives in foods, in general, the following principles should be followed: 1. The food toxicological safety evaluation proves that long-term use within its limits of use is safe for humans. 2. Does not affect the sensory traits and physical and chemical indicators of the food itself, and has no destructive effect on the nutrients. 3. Food additives shall have the use of sanitary standards and quality standards promulgated and approved by the Ministry of Health of the People's Republic of China. 4. Food additives should have a clear test method in their application. 5. The use of food additives shall not obscure the spoilage of food or the purpose of adulteration or forgery. 6. Do not operate or use food additives without hygienic license, no product inspection and pollution deterioration. 7. Food additives can be destroyed or eliminated after processing, cooking or storage after reaching a certain purpose of use. It is safer to not ingest the human body.