Characterization of dominant cultivable lactic acid bacteria isolated from West Algerian raw camel’s milk and assessment of their technological properties

摘要

In Algeria arid regions, camel milk is considered as one of the most important source of dairy products for human diet with potential therapeutic effects. The aim of the study was to characterize isolates of lactic acid bacteria from Algerian raw camel’s milk and to study some of their technologically important properties. Microbiological diversity of Algerian raw camel’s milk was determined by phenotypical, physiological, biochemical and genotypic characteristics. Only 134 Gram-positive and catalase-negative non-spor forming isolates were retained. Theses isolates were chosen for identification using API50CHL and 16S rDNA sequencing. From a total of 134 isolated lactic acid bacteria, 5 presumptive genera were determined, 47 Enterococcus , 29 Lactobacillus , 26 Weissella , 19 Lactococcus and 13 Leuconostoc . All the isolates were characterized by the determination of some technological aptitudes showing interesting features to be used as a starter in the production of fermented dairy in term of proteolytic activity, acetoin and dextran production. Acidification and growth kinetic during 48 h was carried out for the isolates, Lactococcus lactis subsp. lactis biovar. diacetylactis , Lactobacillus rhamnosus and Leuconostoc mesenteroides , allowing to subdivide them in three groups: fast acidifying isolate, medium acidifying isolate and slow acidifying isolate.