Study On Filtration Lactic Acid Bacteria From Pickling Vegetable And High-activity Admixture Bacterium Strain Starter Culture

Pickling vegetable is a sort of traditionary ferment food, it has sepecial sense and abundance nutrition , it is populared for the people. In this paper, lactic acid bacteria were isolated and identified from many sorts of pickling vegetable for having excellent characteristics in acid production and the ability for degradation the nitrate. The fermentation characterisics of these srains were also studied. It has isolated strains and optimization collocation for fine lactic acid bacteria, studied the primary factors which affect manufacturing technology of pickling vegetable. The cheap enrichment medium suited for industrial processing and freeze-drying protectant were screened. The technology of enrichment culture for lactic acid bacteria, cell concentration, lyophilization were studied. The fermentative activity of the freeze-drying starter in cabbage brine were examined.86 strains of lactic acid bacteria were isolated and identified from eight pickling vegetable. Five strains were selected for having excellent characteristics in acid production and the ability for degradation the nitrate. For morphology appraisement and the test for physiology and biochemical event, there are two Lactobacillus plantarum, one, one Lactobacillus pentosus, one Leuconostoc mesenteroides subsp, dextrainicum. The fermentation characterisics of these five srains were also studied.It make Leuconostoc mesenteroides subsp. LNâ‘ , Lactobacillus plantarum JLâ‘¡and Lactobacillus brevis LSâ‘¡pro rate combination arrange in pairs for starter. It sceen out LNâ‘ : JLâ‘¡=1 : 2,LNâ‘ : LSâ‘¡=1 : 2,LNâ‘ : JLâ‘¡: LSâ‘¡=1 :1 : 1 are choiceness starter, and make the three starter in different temperature ferment cabbage, make sure 10℃is the best temperature for the ferment cabbage .Tomato juice medium, carrot juice medium and cabbage medium which are apt to gain and separate are obtained by cell groeth experimented. The result showed that cabbage juice was the best base medium for Lactobacillus brevis LSâ‘¡. The effect of adding 12 kinds of different nutrient factors in cabbage juice medium. The result showed that the optimum enrichment medium obtained by orthogonality test L₉(3⁴) consist of adding 1% peptone, 1% beeves, 0.7% corn liquor, 0.5% glucose and 0.2% K₂HPO₄ in cabbage juice medium. In the optimum enrichment medium, the living-cell number of LSâ‘¡,LNâ‘ and JLâ‘¡were increased by 39 times, 42.5 times and 54.5 times compared with cabbage juice base medium and the same with the living number in the MRS used in lab.The effects of centrifuging force, time on the loss rate, survival rate and harvest rate of lactobacillus was studied. The results showed that the optimum conditions for centrifugation of Lactobacillus brevis LSâ‘¡, Leuconostoc mesenteroides subsp. LNâ‘ and Lactobacillus plantarum JLâ‘¡3672g(6000rpm)for 10min and the highest harvesting rate of living cells were 96.28%, 97.52%, 98.93%.A complex protectant was screened, which could protect cell from damaging during freeze-dry. After freeze-drying, the living-cell number of starter, Lactobacillus brevis LSâ‘¡, Leuconostoc mesenteroides subsp. LNâ‘ and Lactobacillus plantarum JLâ‘¡were over 10¹¹ cfu/g, freeze-dry livability were over 95%. The cabbage fermented by protectant in 10℃. The result were no differental significance compared with traditional culture which show the cabbage can be matured about 6 days and the pH was 3.55.