In response to the growing consumer demand for fresh cheese in summer,
this investigation was aimed to evaluate the chemical and microbiological
characteristics of sheep’s milk and cheese produced in Sicily in the hot summer months.
A total of 810 bulk milk samples collected from 17 farms rearing ewes of the Valle del
Belice breed were analysed for chemical composition, somatic cell count, total bacterial
count and clotting parameters. Samples (n=18) of Protected Designation of Origin
Vastedda della valle del Belice cheese produced in six dairies were collected in
summer, autumn and spring and analysed for chemical composition, microbiological
profile and fatty acid (FA) composition. Univariate and multivariate analyses were
performed to assess variations by season. Sheep’s milk produced in the summer had
higher fat and casein contents, less lactose and urea and slightly higher total bacterial
count and, similar to milk produced in winter, had a weaker clotting ability. Vastedda
cheese produced in spring had less thermophilic lactococci and a high rumenic acid
content. Cheese produced in summer had more fat; less saturated FA; and more linoleic
acid, monounsaturated FA and omega-3 polyunsaturated FA. A dual approach to data
analysis revealed a strong influence of production season on bulk milk and Vastedda
cheese characteristics due to climate conditions and ewes’ feeding regimen. Although
this study provides evidence of the good nutritional properties of summer sheep’s
cheese, management and feeding strategies could aim to further improve the quality of
milk and cheese produced in the summer months