Phenotypic and genotypic characterization of lactic acid bacteria isolatedfrom Pecorino Toscano cheese

Phenotypic and genotypic characteristics of lactic acid bacteria were studi ed to evaluate the microbial diversity of Pecorino Toscano, an Italian chee se with the Designation of Protected Origin, produced from pasteurised shee p milk. Sugar fermentation profiles did not enable unambiguous identificati on of all the strains, which belonged to Lactococcus lactis subsp. lactis, Streptococcus thermophilus and mesophilic lactobacilli. Numerical analysis of the discriminating phenotypes and PCR fingerprinting showed a high strai n heterogeneity. By combining phenotypic and genotypic information, a diffe rent distribution between strains was observed. Although produced from past eurised milk, Pecorino Toscano is characterised by a nide heterogeneity of lactic microflora.