The role of food additives in the modern food industry is becoming more and more important, more and more countries permit the use of food additives. Enacted in 1990, "food additive classification and code", is divided into: their main function of the different acidity regulator, anti-caking agents, defoamers, antioxidants, bleaching agents, bulking agents, gum base agent coloring agent, color protection agents, emulsifiers, enzymes, flavor enhancers, flour treatment agent, agent, water retention agent, nutrition enhancers, preservatives, stable and coagulant, sweeteners, thickeners, and other 21 categories.

Food additives has greatly promoted the development of food industry, and known as the soul of the modern food industry, mainly, it has brought many benefits to the food industry, its main role is as follows:

1. Conducive to the preservation of food to prevent food from corrupt degenerate. Such as: preservatives can prevent food spoilage caused by microorganisms, to extend the shelf life of food, but also can prevent food poisoning caused by microbial contamination, the role of Another example: antioxidants can prevent or delay the oxidative deterioration of food, to provide stability and storability of foods, but also prevents the formation of potentially harmful fat auto-oxidation substances. In addition, can also be used to prevent food, especially fruits, vegetables, enzymatic browning and non-enzymatic browning. Of food preservation is of some significance.

2. To improve the sensory properties of food. Food color, smell, taste, shape and texture is an important indicator for measuring food quality. Appropriate use of the coloring agent, color protection, bleach, food flavors and food additives such as emulsifiers, thickeners, can significantly improve the sensory quality of food to meet the different needs of the people.

3. Maintain or improve the nutritional value of food. Food processing, food fortifier to add some natural nutritional range, can greatly improve the nutritional value of food, which is of great significance to prevent malnutrition and nutritional deficiencies, promote nutritional balance, and improve peoples health.

4. Increase the variety of food and convenience. On the market today has up to more than 20,000 kinds of food choices for consumers, although the production of these foods is mostly through certain packaging and processing methods to deal with, but in production engineering, some of the color, smell, taste with full mostly to varying degrees, add coloring, flavoring, seasoning, and even food additives. It is these many foods, especially the supply of convenience foods, bring great convenience to peoples lives and work.

5. Favorable food processing production to adapt to mechanization and automation of production. Defoamer, filter aid, stability and coagulants used in food processing, can be beneficial to the food processing operation. For example, when the use of gluconic acid δ lactone as a tofu coagulant, can be conducive to mechanization and automation of tofu production.

6. Meet other special needs. The food should be possible to meet the different needs of the people. For example, people with diabetes can not eat sugar, you can use non-nutritive sweeteners or low sweetener such as sucralose or Aspartyl-L-phenylalanine methyl ester made from sugar-free food supply.