In order to prevent all kinds of processed foods, fruits and vegetables horn spoilage, can use physical methods specific to corrosion or chemical methods. Chemical method is the use of chemical substances to inhibit microbial growth or death to these organisms. These chemicals shall preservatives. Preservatives can have the same broad and narrow: the narrow sense refers to the main preservative sorbic acid, benzoic acid and other chemicals directly into food substances; broad preservative addition to including within the meaning of a narrow chemical preservatives, but also including those normally that is the role of seasoning and a preservative substances, such as salt, vinegar, and those who do not usually directly into food, food storage process in the application of disinfectants and fungicides and so on. As a food additive is defined as the application of preservatives to prevent food spoilage, deterioration, extend food shelf life and inhibit propagation of microbes in food substances. However, the role of food in the same condiments such as salt, sugar, vinegar, spices, etc. are not included. As a food container with disinfectant for bacteria in the disinfectants are not included. Abroad for food preservatives, the United States there are about 50 species, 40 species in Japan. China allows the use of preservatives for the 28 species. To properly prevent food spoilage, in addition to choose the appropriate preservative, it should also pay attention to the role played comprehensive food preservation, such as food processing, packaging materials and their functions, as well as food storage, transport, conditions of sale and so on. And important is the continuous development of applications more secure, effective and economical preservative varieties. As scientific and technological development, particularly the progress of detection, it was recognized that the past use of certain preservatives, such as borax, formaldehyde, salicylic acid and diethyl coke, etc. on food preservation at the same time may also bring certain harm to the human body have been disabled. On the other hand, some of the new preservatives, such as lactic acid streptococcus titanium (Nisin), etc., because of its more secure and effective use by people to further expand. At the same time people are still continue to seek to develop new and better varieties. In practice, due to the diversity of microbial species and preservatives such as the role of the characteristics of the present, people are committed to strengthening the development of complex technology and applications. This includes both the co-ordination between the different preservatives, but also include preservatives and antioxidants and other food additives mixture between technology, while also developing different formulations and dosage forms to meet different needs. The following only in respect of the license preservatives species in China.