The Preparation And Application In Circulatory Fermentation Paocai Of Efficient Lactic Acid Bacteria Directed Vat Set

The Paocai contains a small amount of lactic acid bacteria, a high level of salinity and nitrite, a long fermentation cycle. This experiment is designed to solve the problems of Paocai industry from the Lactic acid bacteria and the fermentation process culture two aspects. First, chose the strains which are appropriate growth in Paocai, high density trained, freeze-drying. Second, through research the balance of mature Paocai, added the corresponding raw materials to control the quality of Paocai, then realized circulation fermentation of the Paocai. It will ensure the stability of the product quality, save labor and cost investment, promote the industrialization and scale process of Paocai.1. The optimization culture condition of the high density LABThis paper from the culture medium, filling materials training and constant pH training, three aspects to find the optimized cultivation conditions of the strains Through the three kinds of lactic acid bacteria culture medium for comparison, the most suitable culture medium for the is strains PP, P158is MRS. Through the comparison of the three fill material ways, adding nutrients before the end of the logarithm growth period bring the best effect. The group with20%Na2CO3solution adjust pH in the fermentation process, was better than Control group. Filling materials training and constant pH training Pediococcus pentosaceus PP and L.plantarum P158, the highest number of living bacterium respectively can reach9.01×109cfu/mL and2.14×1010cfu/mL, about95%higher than the regular training.2. The optimizing Vacuum freeze-drying conditionThe optimizing Vacuum freeze-drying condition of strains PP, P158is frozen in liquid nitrogen for15min. The optimal protectants formula of strains PP is trehalose7%, sugar7%, sodium glutamate3%, suspended in10%skim milk. The optimum protectants formula of Strains P158is trehalose7%, sugar7%, sodium glutamate5%, suspended in10%of skim milk. The freeze-dried surial of Pediococcus pentosaceus PP was95.8%, and the number of living bacterium after freeze-dried was8.63× 109cfu/mL, about6.43×1010cfu/g after conversion; The freeze-dried surial of L.plantarum P158was75.6%, and the number of living bacterium after freeze-dried was1.61×1010cfu/mL, about7.32×1011cfu/g after conversion.3. The application of Culture and circulation fermentation of PaocaiBy comparing of the kamahi’ s difference of function bacteria fermentation, kamahi’s bisk fermentation, natural fermentation Paocai in sensory indexes, physical and chemical indexes, microbiology indicators, we can conclude that the function fermentation pickle is superior to other two fermentation method in quality and food safety. Control the adding quantity of sugar, salt and the juice of spices in the fermentation process can realize the cycle of Paocai fermentation, single factor experiment and orthogonal experiment determined the adding quantity of salt, sugar and the juice of spices is respectively3.75%,3.5%and3.5%.Research results not only is the foundation of the preparation of efficient lactic acid bacteria directed vat set(DVS) and Paocai circulation fermentation, but also provide reference to the industrialization of inoculate cycle fermentation of pickled to, so it has great theoretical significance and practical application value.