Isolamento e caratterizzazione di ceppi microbici autoctoni dei formaggi siciliani, Pecorino Siciliano e Ragusano

In this research the lactic microflora of two typical Sicilian cheeses (Ragusano and Pecorino Siciliano) produced by traditional technologies was investigated. Several genera and species of lactic acid bacteria (LAB) were recognised and the phenotypic and genotypic characterisation of the 200 coccal- and rod-shape isolates highlighted a huge intra-specific biodiversity. Enterococci were found as the most relevant component of the LAB population of these cheeses; the detection of S. macedonicus in the Ragusano cheese is noteworthy. To explore the suitability of the isolates to be used as potential starters, some traits related to the safety, such as the absence of antibiotic resistance, haemolysis or production of biogenic amines, or the presence of important functional properties, i.e. the ability to release metabolites against ACE (Angiotensin-I-Converting Enzyme) or bacteriocins, were determined. The obtained results indicate the existence in these Sicilian cheeses of proper candidate strains which can be deeply explored for the development of specific and more standardised cheese-making processes using autochthonous starters