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Tempeh fermented soybean food is a common, usually black beans, soy beans and other legumes prepared as a substrate, the use of artificially added or attached to a substrate fermentation by specific microbes in the air. In accordance with the fermentation microbial different, tempeh can be divided into several different types of Rhizopus and Aspergillus, Mucor, and bacterial type; whether to add salt in the fermentation process, and can be divided into salty tempeh and Seme sojae; addition, based on how much moisture content in tempeh tempeh can be divided into dry the tempeh, wet tempeh and water tempeh. In our country, Mucor type tempeh, the Aspergillus type tempeh and bacteria tempeh part exist. Famous foreign places tempeh and natto. Yunnan's diverse natural environment and eating customs, making Yunnan has rich resources of tempeh, which the the fermentation microbes also presents distinctive diversity, especially in the presence of lactic acid bacteria in traditional fermented tempeh in some areas of Yunnan, and microbial fermentation advantage . Lactobacillus is the use of glucose and other carbohydrates fermentation general term for a group of bacteria to produce large amounts of lactic acid. It's just a habit with a true sense of academic name called, not microbial taxonomy. The survival of lactic acid bacteria is very complex, including saprophytic, parasitic. It is widely present in the human and plants and animals, individual species are pathogenic to humans and animals. The vast majority of lactic acid bacteria is the food, medicine and health, agriculture, medical and scientific research on the important bacteria. The lactic acid fermentation liquid in the composition is very complex, wherein many substances have antibacterial effects, mainly includes bacteriocins, organic acids and hydrogen peroxide. Wherein the organic acid is relatively scarce, and mainly focus on the analysis and quantification of organic acid species, while the major chemical synthesis of organic acids antibacterial experiments in vitro simulation, the study has some limitations, organic acids The synergy of the impact, as well as other antibacterial active substances whether there are not yet clear. This study, the use of thin layer chromatography organic acids lactic acid bacteria fermentation broth five major qualitative analysis, optimize chromatographic conditions, followed by the UV spectrophotometry quantitative analysis of five kinds of organic acids in different carbon source for fermentation culture after the content, combined with the antimicrobial test results show that, as a reference to glucose as the carbon source, when the use of starch as a carbon source, the overall inhibitory effect weakened, a slight increase in citric acid content of most strains. Tartaric acid content of increase is relatively large, and lactic acid, oxalic acid and malic acid content had decreased. Sucrose as a carbon source, citric acid, reduced the content of lactic acid, oxalic acid, tartaric acid and malic acid have increased their overall inhibitory effect weakened. Lactose as a carbon source, in addition to the decrease in malic acid content, and other organic acids in varying degrees increased inhibitory effect has also been enhanced. Fructose as the carbon source, citric acid and lactic acid content is decreased, and oxalic acid, tartaric acid and malic acid content is increased, and its inhibitory effect, however, is weakened. This analysis and concluded that lactic acid organic acids in lactic acid bacteria inhibitory factors, citric acid, followed by malic acid, oxalic acid and tartaric acid inhibitory effect is relatively small. Studies have shown that organic acids lactic acid bacteria is the major inhibitory factor, but only when one of the organic acids and other antibacterial substances together to play efficient inhibition. The results of this study provide some theoretical support, and provides a theoretical basis for its applied research in the field of food biotechnology preserved bacteriostatic mechanism of lactic acid bacteria.
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