Characterization of thermophilic streptococci isolated from rustic white cheese

Abstract

The thermophilic streptococci are dominant members of the microflora of several types of cheese produced with a natural starter. A total of 205 isolates of thermophilic streptococci were obtained from 70 samples of white cheese which had been collected from producing areas of different regions of Syria during 2009 and 2010. The isolates were cocci gram positive and catalase negative. From these isolates, 120 were identified as Enterococcus spp. including: 72 isolates of E. faecium, 35 isolates of E. fecalis and 13 isolates of E. durans. In addition, 70 isolates were identified as Streptococcus including: 50 isolates of S. thermophilus, and 20 isolates of S. equines. Fifteen isolates of cocci grew at 45°C with spherical morphology, gram positive and catalase negative. The PCR technique could be efficiently used for identifying and typing the thermophilic streptococci.