Inhibition of Yesinia enterocolitica in Ready to Eat Vegetable Salad by Lactic Acid Bacteria Isolated from Fermented Foods and Beverage

摘要

In this study, Lactobacillus sp. KJ722775 andLactobacillus brevis KJ722775 were selected for study ofantagonistic against Y. enterocolitica at refrigeration temperature. Y.enterocolitica was added to ready to eat vegetables salad andcoinoculated with Lactobacillus sp. and L. brevis separately, storedat 4 oC for 14 days. In shredded vegetables salad the population of Y.enterocolitica in the control sample (no LAB isolate added) increasedfrom 5.45 log CFU/ml (0 day) to 7.81 log CFU/ml (14 day) (Figure4.42). On the other hand, shredded vegetables salad samplesinoculated with Lactobacillus sp. PLA27 and L. brevis PLA29 foundthat the numbers of Y. enterocolitica decreased by 0.18 log CFU/mland 0.43 log CFU/ml respectively over the 14 days of storage whencompared to their initial count on day 0. Cell-free supernatants ofselected antagonistic bacteria were studied to determine the nature ofthe antimicrobial compounds produced. The low pH and productionof lactic acid were the main factors for inhibition of growth of Y.enterocolitica.