LIPOLYSIS IN CHEDDAR CHEESE MADE WITH SODIUM-CHLORIDE, POTASSIUM-CHLORIDE OR MIXTURES OF SODIUM AND POTASSIUM-CHLORIDE

Cheddar cheese from a split lot of curd was prepared with or without added NaCl, KCl or mixtures of NaCl/KCl (2:1, 1:1,1:2 and 3:4, wt/wt basis) to achieve final salt concentrations of approximately 1.50 or 1.75 %. Lipolysis in cheeses was determined at intervals during 36 weeks of ripening at 3+/-1-degrees-C. Results of the copper soap method indicated that levels of free fatty acids (FFA) had increased after 36 weeks in all control and experimental cheeses. There were no significant differences (P > 0.05) in levels of FFA among salt-free Cheddar and cheeses made with NaCl, KCl or mixtures of the two salts. Results from a gas chromatographic method showed no qualitative differences in FFA liberated after 36 weeks of ripening of unsalted cheese and cheeses salted with NaCl, KCl or mixtures of these salts. The FFA in cheeses with an average of 1.42 and 1.57 % NaCl or 1.68 % KCl were 1145, 947 and 1073 ppm, respectively, whereas the FFA in cheeses with an average of 1.54 % (2:1, 1:1 and 1:2) and 1.65 % (3:4) NaCl/KCl mixtures were 1169, 1098, 1109 and 1080 ppm, respectively. Unsalted cheese had an average FFA concentration of 1529 ppm. Results indicate that replacement of one-third or more of the NaCl in Cheddar cheese with KCl did not enhance development of hydrolytic rancidity in the cheeses.