CARATTERIZZAZIONE DI BATTERI LATTICI DI UN FORMAGGIO TRADIZIONALE A PASTA FILATA

In this paper are reported the results of the characterization of the lactic acid microflora isolated from Sardinian “provoletta”, a traditional pasta filata cheese obtained from cow’s milk. Cheese samples from two batches were taken in triplicate from three dairy plants after 7 and 21 days of ripening. Each sample was analyzed for mesophilic and thermophilic lactic acid bacteria (LAB). From plates, 118 isolates were identified by Rep-PCR GTG5, species-specific PCR and DNA sequencing. The identified LAB belonged to 7 different species: Lb. paracasei, Lb. rhamnosus, Lb. delbrueckii, Lb. fermentum, E. faecalis, E. faecium e Lc. Lactis. Enterococci were the most common isolates, they were recovered from all the dairy plants and from all the products analysed at 7 and at 20 days of ripening. Although with some differences within the various producers, the technology used aids mesophilic LAB growth, guaranteeing a large biodiversity protection.