FACTORS AFFECTING THE CONJUGATED LINOLEIC-ACID CONTENT OF CHEDDAR CHEESE

The effects of package type (cans and nylon vacuum pouches), milling p H (5.5, 5.7, and 5.9), additives [butylated hydroxyanisole (BHA), tyro sine, and lysine], and aging (0, 1, 3, and 6 months) on the conjugated linoleic acid (CLA) content of Cheddar cheese was determined. Fatty a cid distributions and CLA, moisture, protein, lipid, and titratable ac idity contents in raw milk and aged cheeses were determined. The CLA c ontent in canned cheese (3.03 mg/g lipid) was significantly higher tha n in a vacuum pouch packed cheese (2.70 mg/g lipid) after 6 months of aging. Milling pHs of 5.5 and 5.9 and the addition of BHA, tyrosine,an d lysine resulted in significantly lower CLA contents in cheeses aged for 6 months than the control. Multiple linear regression showed that lipid and protein contents contributed to CLA content positively. The content of oleic acid contributed significantly to the relationship be tween CLA and fatty acids.