Tecnologia di produzione e caratteristiche microbiche del formaggio Valtellina Casera

Valtellina Casera and Bitto are the most important cheeses of Valtellina valley. Valtellina Casera cheese is produced throughout the year and is very important for the economy of this area. Valtellina Casera characteristics, production area and ripening conditions are defined according to the PDO Regulation n. 1263 (01/07/1996). 26 trials (13 in summer and 13 in winter) were performed in 13 small industrial plants. Cheesemaking technologies were studied and microbiological analysis were performed on both the milk and the curd, (SBC, contaminating microorganisms, coliforms, E. coli, Staphylococcus aureus, yeasts, moulds and lactic acid bacteria). When ripened cheese was 4 months and 70 days Salmonella sp. and Listeria monocytogenes were analysed. Compositional, chemical and organoleptic analysis were also carried out on the ripened cheese. This study shows that some technological parameters (in particular the cooking temperature) influence the final microbiological and sensory characteristics of cheese. After ripening, Valtellina Casera is characterized by a rich lactic microflora and can be considered a safe product from the hygienic point of view.