Relation of Flavor Development in Cheddar Cheese to Chemical Changes in the Fat of the Cheese

Abstract

Typical Cheddar cheese flavor was found to be related to a balance of free fatty acids and acetate. Experimental lots of cheese, which had the finest flavor and highest score, had a concentration of free fatty acids plus acetate of 12 to 28 μmoles per gram of cheese solids after 180 days of aging or a ratio of free fatty acids to acetic acid between 0.55 to 1.0. Gas-liquid chromatography analysis showed that identical fatty acids were liberated in each lot of cheese. All even-numbered carbon fatty acids from C4 to C18 were found in each lot from the first day of manufacture. Cheese criticized as having rancid, fruity, and fermented flavors had two to three times the concentration of C10, C12, and C14 fatty acids as did cheese of fine flavor.Cheese made from skimmilk did not acquire either Cheddar flavor or body characteristics during ripening of six or 12 months. Only Cheddar cheese containing 50% fat or more in the dry matter developed a typical flavor, whereas cheese with less than 50% fat did not. As fat in the cheese decreased, the concentration of fatty acids decreased, but the acetate increased so the ratio between free fatty acids/acetate became undesirable. Typical flavor developed in cheese made either from raw or from pasteurized whole milk, provided the bacterial count of the milk was not abnormally high or low. Greater concentration of free fatty acids developed during ripening in cheese made from pasteurized milk, when the total plate count was high in the raw milk,>10,000,000/milliliter, than in cheese made from raw milk with a low bacterial count, 1,000 to 5,000 /milliliter.