Abstract:

This review deals with recent research advances on the biodiversity of Chinese traditional foods lactic acid bacteria (LAB). Traditional foods like yoghourt, kumiss, kefir and fermented camel milk are abundant in LAB. The distribution of LAB taxa is highly variable from one traditional food to another. Isolation of LAB taxa mainly depends on the sample plating methods, incubation media and conditions. It is therefore difficult to define associations between population composition and either the type of traditional food or the geographic location. Identification of isolated strains needs a ployphasic approach, including a combination of phenotypic and genotypic methods, among which the latter often based on the polymerase chain reaction (PCR) and encompassing 16S rRNA sequencing and DNA-DNA hybridizations. The main obstacle in current identification approach of LAB strains is the lack of a robust and exchangeable identification system for all LAB species. Some proposal are come up in this paper : 1) to establish a reliable and scientific system in sample collection, strain isolation and identification. 2) to isolate new characteristic strains. 3) to explore and develop new products contained LAB. 4) to intensify the research on the function and mechanism of isolated strains.

Key words: traditional dairy foods, LAB, isolation, identification