Physicochemical and microbiological study of'shmen',a traditional butter made from camel milk in the Sahara(Algeria):isolation and identification of lactic acid acteria and yeasts

摘要

Microorganisms(aerobic bacteria,conforms,lactic acid bacteria,psychrotrophs,lipolytic bacteria and yeasts)were isolated from 20 samples of shmen,a traditional clarified butter made from sour camel milk in the Algerian Sahara.The values of pH,titratable acidity,NaCl,total solid,moisture,and fat content ranged from:3.11-4.97,0.19-0.36,1.04-2.15,64.03-65.11,34.40-34.99,and 49.90-56 respectively.A total of 181 isolates of lactic acid bacteria were identified as Lactobacillus plantarum(40 strains),Lactobacillus delbrueckii ssp.bulgaricus(35 strains),Lactococcus lactis ssp.lactis biovar diacetylacti(22 strains),Lactococcus lactis ssp.cremoris(18 strains),Lactobacillus paracasei ssp.paracasel(10 strains), Leuconostoc pseudomesenteroides(9 strains)and Leuconostoc gelidum(12 strains)Enterococcus faecium(35 strains).Yeasts were isolated from all samples(55 isolates).Of these,40 were identified as Saccharomyces cerevisiae and 15 isolates were identified as Saccharomyces sp.