title: Effect of somatic cell count on Prato cheese composition.
abstract: The objective of this research was to evaluate the effect of 2 levels of somatic cell counts (SCC) in raw milk on Prato cheese composition, protein and fat recovery, cheese yield, and ripening. A 2 x 6 factorial design with 3 replications was performed in this study: 2 levels of SCC and 6 levels of storage time. Initially, 2 groups of dairy cows were selected to obtain low (<200,000 cells/ mL) and high (>600,000 cells/mL) SCC in milks that were used to manufacture 2 vats of cheese: 1) low SCC and 2) high SCC. Milk, whey, and cheese compositions were evaluated; clotting time was measured; and cheese yield, protein recovery, and fat recovery were calculated. The cheeses were evaluated after 5, 12, 19, 26, 33, and 40 d of ripening according to pH, moisture, pH 4.6 soluble nitrogen, 12% trichloroacetic acid soluble nitrogen as a percentage of total nitrogen, and firmness. High-SCC milk presented significantly higher total protein and nonprotein nitrogen and lower true protein and casein concentrations than did low-SCC milk, indicating an increased whey protein content and a higher level of proteolysis. Although the pH of the milk was not affected by the somatic cell level, the cheese obtained from high-SCC milk presented significantly higher pH values during manufacture and a higher clotting time. No significant differences in cheese yield and protein recovery were observed for these levels of milk somatic cells. The cheese from high-SCC milk was higher in moisture and had a higher level of proteolysis during ripening, which could compromise the typical sensory quality of the product.
authors.affiliation: State University of Campinas-UNICAMP, Faculty of Food Engineering, Department of Food Technology, Caixa Postal 6121, CEP 13083-970 Campinas/São Paulo, Brazil.
authors.forename: G
authors.initials: G
authors.lastname: Mazal
authors.forename: P C B
authors.initials: PC
authors.lastname: Vianna
authors.forename: M V
authors.initials: MV
authors.lastname: Santos
authors.forename: M L
authors.initials: ML
authors.lastname: Gigante
mesh_terms: D000818:Animals; D002417:Cattle; D002452:Cell Count; D002611:Cheese / Q000032:analysis*; D005260:Female; D005511:Food Handling / Q000379:methods; D006863:Hydrogen-Ion Concentration; D008892:Milk / Q000737:chemistry / Q000166:cytology*