The Isolation, Identification And Probiotic Properties Of Lactic Acid Bacteria From Sauerkraut

The experiment selected pickled cabbages as the research objects, lactic acid bacteria was isolated from traditional farmer homemade pickled cabbage and identificated preliminarily. Then the author screened out strains of good probiotic properties for research and studied the growth characteristics of them and has done the purebred fermentation experiment. The main conclusions are as follows:184strains of lactic acid bacteria in this study were isolated from14samples of traditionally home-made sauerkraut in Inner Mongolia, among of them were24strains of lactobacillus and60strains of lactococci.2According to themorphological characters, physiological and biochemical reaction and suger fermentation character of bacteria, the results showed that84strains of lactic acid bacteria were Lb. plantarum, Lb. rhamnosus, Lb. brevis, Lb. acetotolerans, Sc. salivarius, Sc. thermophilus, Ec. faecalis, Lc. plantarum, Leu. mesenteroides.3Screening from the84strains of lactic acid bacterias, I obtained5strains of Lactobacillus which have a good performance of acids and bile salt resistance. Here by names them as Lactobacillus brevis S1-3respectively and Lactobacillus plantarum Sc6-2, Sc6-3, Sc9-6and Lactobacillus rhamnosus Sc6-7.4Screening out of5Lactobacillus strains in0.3%bile environmental effects of6h and pH3environment3h, gets higher survival rates; the pH value of3,4of the artificial gastric juice has a strong ability to survive, at pH6.8artificial intestinal fluid effect after24h, S1-3and Sc9-6still maintained higher living bacteria number, Sc6-3, Sc6-7, Sc9-6live bacteria counting drops more apparent; Lactobacillus brevis S1-3on cholesterol degradation rate of the strongest, the degradation rate for61.79%, Lactobacillus plantarum Sc6-3on cholesterol degradation rate is relatively high, the degradation rate for43.91%, Lactobacillus plantarum Sc6-2, Sc9-6and Rhamnus sugar Lactobacillus Sc6-7on cholesterol degradation rate of some of the weak, the degradation rate is respectively34.72%,31.10%and13.64%.5Out of3Lactobacillus strains on the growth characteristics of Lactobacillus brevis test showed:S1-3、Sc6-3、Sc9-6three Lactobacillus strains of optimum growth temperature of both30-35℃, able to tolerate the largest salt concentration was7%, and3strains of bacteria in the growth of0h-2h in the delay period, the2h-14h as the logarithmic phase, from thel4h entered a period of stability, and stable time of up to1Oh.6To screen the best strain combinations for Dl (S1-3:Sc9-6=1:1). The optimal fermentation parameters:fermentation temperature20℃for3days, fermentation time, inoculum volume3%, salt5%. The use of Dl group mixed strains produce sauerkraut, in early fermentation period (ld-3d), pH decreased rate and acid production rate is far greater than the blank control group, within the same fermentation conditions, the test group acid yield is9times of controls. Dl test group and blank control group, group Dl nitrite content decreased rapidly, edible safety period of early2-3days.