Study On Special Starter Of Lactic Acid Bacteria For Pickles

Lactobacillus is the main microbe in the production of pickles, it plays an important role on the formation and quality of pickles special flavor. In the actual production of pickles, there are some hidden problems about the food quality, traditional mode has been taken to produce pickles, the period of ferment is long and the quality of the production is astable. In this study, we separated and purificated lactobacillus from the water of pickles, screening lactobacillus strains which has a high rates in the degradation of nitrite, can produce more acid and has apparent inhibitory effect to bacterium, adopting16Sr DNA PCR analysis technology of nucleotide sequences to identify lactobacillus biology. The selected strains should be researched about the best composition in medium which has been in high-density cell cultivation. Making an exploration about the freeze-drying conditions of lactobacillus to determine the conditions of making lactobacillus active yeast.According to the conditions of screening, we can preliminary screen strains of lactobacillus using chemical method, and on this basis to adopt16Sr DNA PCR analysis technology of nucleotide sequences to identify lactobacillus biology. The two strains isolated from Lactobacillus is Leuc. Mesenteroides and Lactobacillus plantarum. Determining the growth conditions of Leuc. Mesenteroides and Lactobacillus plantarum, screening of high-density culture medium strain components, after the enrichment culture, the pH of Leuc. Mesenteroides is4.72, viable count is1.4×1010cfu/ml).The Lactobacillus plantarum’s pH4.22, enrichment of viable cells can reach to2.1×1010cfu/mL.To explore the conditions of lactobacillus active yeast, we discovered the best centrifuge conditions, found out the centrifugal time, centrifugation speed and centrifugation temperature of Leuc. Mesenteroides and Lactobacillus plantarum.centrifuged under these conditions, the recovery rate can reached to95.5%and92.7%, respectively.Experimental results show that best protection conditions of Leuc. Mesenteries for freeze-drying are:8%trehalose,8%glycerol,4%casein,5%B-cyclodextrin, the freeze-drying survival rate under these conditions can reached to78.8%; The best protection conditions of Lactobacillus plantarum are:5%trehalose,5%glycerol,8%sucrose,5%β-cyclodextrin, the freeze-drying survival rate can reached to75.8%. In this method, the Freeze-drying Lactobacillus yeast can be used for pickles production, which will shorten the fermentation time, provide some experimental basis and theory for the production control and safety of pickles.