Influence of cheese-making technology on composition and microbiological characteristics of Vastedda cheese

Vastedda is a Sicilian pasta filata sheep cheese made from raw milk without starter addition, traditionally consumed fresh on the local market. To extend its consumption also out of Sicily, a prolonged shelf-life is needed. Production technology, chemical and microbiological aspects of fresh Vastedda cheese and within 60 days of storage were studied. Vastedda, according to Codex Alimentarius, resulted a semi-hard, medium fat cheese, but the large variability of composition makes the definition of a narrow standard of the product difficult. Lactic acid bacteria were the dominant microflora in spite of the heat stress given by the stretching of the curd. Listeria monocytogenes and Salmonella spp., were absent and coagulase positive staphylococci were always lower than 100 cfu/g. The variability among producers is amplified by the variability of the cheese during shelf-life. Sugars and organic acids content largely changed during the 60-day storage, mainly for the brine unsalted variety. To continue to identify this cheese as a fresh one, the storage of traditional Vastedda cheese should not be longer than 30 days.