Isolamento e studio della microflora autoctona caratteristica di alcune produzioni casearie lombarde

Specificity and peculiar sensory characteristics of traditional cheeses are strictly related to the high level of biodiversity of the indigenous microflora. Over the centuries the technologies of these cheeses have selected complex bacterial ecosystems. In the present study 120 strains were isolated from 13 raw milk cheeses of north-west Italy. The strains were characterized for their morphology and for the presence of technologically relevant biochemical properties such as acid production and redox activity, lipolytic and proteolytic activities in milk. All the strains were identified at species level by phenotypic identification based on carbohydrate fermentation profile galleries. Differences in technological properties were found between and also inside the species. Selective pressure carried out by the environment (most of the selected isolates for this investigation were coming from mountain productions), the breeding methodology and the technology (cheeses were mostly raw milk, cooked or semi-cooked and long ripening cheeses) lead to build-up biotypes with different characteristics.