Diversity of lactic acid bacteria in vegetable-based and meat-based fermented foods produced in the central region of Vietnam

Abstract

The diversity of lactic acid bacteria (LAB) in naturally fermented foods produced in Hue, a city in the central region of Vietnam, was examined. From local markets, a total of 25 samples of three vegetable-based fermented products, specifically dua gia (bean sprouts), dua cai (cabbage), and mang chua (bamboo shoots), and two meat-based fermented products, specifically nem chua (uncooked pork) and tre (cooked pork) were obtained. The LAB diversity was assessed by quantitative real-time polymerase chain reaction (PCR) and qualitative denaturing gradient gel electrophoresis. Lactic and acetic acid contents were greater in meat-based products than in vegetable-based products. Major LAB species found in vegetable-based products ( Lactobacillus plantarum, Lactobacillus fermentum , and Lactobacillus helveticus ) were different from those identified in meat-based products ( Pediococcus pentosaceus , Weissella cibaria , and Lactococcus lactis ). The total bacterial population was approximately 10 9−10 copies/g regardless of the food item, with the proportion of Lactobacillus spp. determined to be from 78% ( dua cai ) to 94% ( nem chua ).