Cheddar Cheese Flavor. II. Changes in Flavor Quality and Ripening Products of Commercial Cheddar Cheese during Controlled Curing

Abstract

Summary Fourteen lots of Cheddar Cheese were obtained immediately following manufacture from commercial factories selected at random in New York, Wisconsin, Oregon, and Ohio. The cheese was cured for 2 mo. at 50° F., followed by curing at 40° F. for 10 mo. The following analyses were performed periodically: grading, evaluation for characteristic flavor, ammonia, hydrogen sulfide, free fatty acids, free amino acids, acidic and neutral carbonyl compounds, pH, and total bacterial count. The initial quality of the cheese ranged from U.S. Grade A to Below Grade, with most of the cheese showing variation in quality during the 12-mo. curing period. In general, concentrations of ammonia, free amino acids, and free fatty acids increased continuously during curing, whereas hydrogen sulfide and total bacterial counts fluctuated. Raw milk cheese contained higher concentrations of hydrogen sulfide than pasteurized milk cheese, with no conclusive difference being apparent in ammonia, free amino acids, and free fatty acids. Statistical analysis of the results indicated significant correlations at the 5 and 1% level between characteristic Cheddar Cheese flavor scores and pH, ammonia, and hydrogen sulfide after 3 mo. of curing. The flavor of the Cheddar Cheese appeared to be related more to the ratio of free fatty acids and hydrogen sulfide concentrations than to any other compounds or combinations of the compounds included in this study. The merits of relating characteristic Cheddar flavor to free fatty acids and hydrogen sulfide, and the possibility of using these compounds as an index of Cheddar Cheese flavor, are discussed.