This year's CCTV "3.15" party exposed the "house collapse" of laotan pickled vegetables, which spread widely, and even fermented foods such as tofu milk, soybean paste, natto and soy sauce followed. Many people think that fermented food, like pickled food, has experienced a long storage and fermentation process, during which many molds will grow, so there must be safety problems. Is that really the case? "If a regular manufacturer operates the fermented food produced according to the specifications, consumers can eat it at ease. There is no need to worry." Wang Hao, a professor at the school of food science and engineering of Tianjin University of science and technology, explained that the production of these fermented foods really needs the help of mold, but this "mold" is not another "mold". There are many kinds of molds. Not all molds are harmful to human body. Some molds, such as Penicillium and Streptomyces, are not only harmless to human body, but also cure diseases. Wang Hao pointed out that the molds commonly used in the production of soybean paste and fermented bean curd include Aspergillus oryzae, Aspergillus niger, Aspergillus soy sauce, Mucor grandis, Mucor, Rhizopus, Monascus, etc. these molds are artificially selected and proved to be non-toxic, completely edible and harmless to human body. Moreover, these molds can also secrete various enzymes, including protease, peptidase, glutaminase, plant tissue decomposition enzyme, etc. among them, protease and peptidase can decompose the protein in raw materials into polypeptides and a variety of amino acids. Wang Hao said that for example, tofu milk, soy sauce and soybean paste all contain high salt, so it is almost difficult for microorganisms to survive in an environment with high concentration of salt. As long as the national health standards are strictly implemented and there is no pathogenic mold in the production process, these fermented foods are harmless, but it's OK to eat them. Moreover, most of these fermented foods are made of soybean, and the nitrate content in soybean is very small, so there will not be much nitrite in the fermentation process. However, Wang Hao reminded that this kind of food is not easy to store for too long. Once it is stored improperly, it may produce carcinogenic mold - Aspergillus flavus. (outlook new era)