Screening,Identification and Evaluation of Lactic Acid Bacteria WFC 414 and WFC 502 for Apple Juice Fermentation
The lactic acid bacteria with excellent fermentation potential were separated and screened for fermented apple juice using pickles as materials in this experiment. These strains were identified with the methods of morphology,physiology and genetics. The fermentation potential and survival ability in a simulated gastrointestinal environment of these strains were evaluated. The experimental results showed that two LAB strains with excellent fermentation potential were Lactobacillus paracasei WFC 414 and Lactobacillus plantarum WFC 502. The viable counts of WFC 414 and WFC 502 in fermented apple juice for 48 h reached 8.81 and 9.33 log CFU/mL respectively,while their survival rates reached 92％,95％,and 80.7％,83.6％ respectively,in a 2 h simulated gastric fluid and 4 h simulated intestinal fluid. During lactic acid fermenta-tion of 4 d,WFC 414 and WFC 502 reduced the content of soluble sugars and malic acid in apple juice and produced large amounts of lactic acid (3.48 and 5.94 mg/mL respectively). There was alteration of volatile aroma components in fermentation apple juice,esters and alde-hydes were reduced by both strains,while the content of alcohols,acids and ketones was elevated to increase the sweet,fruity,floral aroma of fermented apple fruit juice. These results suggest that WFC 414 and WFC 502 have great potential for application in the fermented juice indus-try.
万方数据
维普
