ASSESSMENT OF PROTEOLYSIS AND LIPOLYSIS IN SERRA CHEESE - EFFECTS OF AXIAL CHEESE LOCATION, RIPENING TIME AND LACTATION SEASON

The degrees of proteolysis and lipolysis in Serra cheese were measured in cheese samples obtained from experiments laid out as a three-way f actorial design replicated twice. The independent variables studied we re the location within the cheese (from the center to the surface), th e position in the lactation season (from October to June) and the ripe ning time (from 0 to 35 days). All three variables had statistically s ignificant effects on the concentration of water soluble peptides (WSP ), but only the ripening time and the period within the lactation seas on affected the fat acidity (FA). The extents (after the given ripenin g period) and the rates (averaged over the ripening period) of generat ion of WSP and FA were highest for spring and lowest for autumn. The l owest values for both the proteolysis extent and the proteolysis rate were obtained for the rind. The rates of proteolysis and lipolysis ten ded to decrease with ripening time; most of the lipolysis occurred dur ing the first week, but proteolysis was still in progress by 35 days o f ripening.