Isolation and Identification of Yeasts Contaminated buffalo's Raw Milk

Abstract

This study was conducted to know the types of yeasts that contaminated buffalo's raw milk, and study its ability to produce protease and lipase enzymes, also study the efficiency of the process of pasteurization in its break.Samples were collected from AL-Dathab AL-Abuead village in the province of Wassit, during summer season (beginning from May 2010 to the end July 2010) 60 samples were tested in Microbiology department in the Collage of Medicine in Wassit University.The percentage of infection in yeasts was high 73 % in samples of buffalo raw milk in the summer season, the yeasts isolates were 63 and 8 types of yeasts have been diagnosed:Candida albicans 25.4%, C.tropicalis 19.1%, Rhodotorula spp.15.9, Saccharomyces spp.14.3%, C .krusei 9.5%, C.parapsilosis 6.3% , Crptococcus neoformans 6.3%, C.famata 3.2% .The yeasts that isolated had ability to secrete the enzyme protease, except yeast C. Parapsilosis , while , all the yeasts isolates were not have the ability to secrete enzyme lipase except Rhodotorula spp., Saccharomyces spp., Crptococcus neoformans.The results showed that the process of pasteurization had a very high efficiency in the elimination of yeasts, while all samples of pasteurized milk ( 20) were negative for yeasts isolation.