EVALUATION OF CONJUGATED LINOLEIC-ACID CONCENTRATIONS IN COOKED BEEF

Conjugated linoleic acid (CLA) concentrations in raw steaks (ribeye, round, T-bone, and sirloin) ranged between 3.1 and 8.5 mg of CLA/g of fat. Freshly cooked rare (60 degrees C) or well done (80 degrees C) ground beef patties (fried, baked, broiled, or microwaved) contained between 6.6 and 8.2 mg of CLA/g of fat. When CLA concentrations were compared on a milligrams of CLA per gram of fat basis, there were no significant differences in CLA among either cooking methods or degrees of doneness. When CLA concentrations were compared on a milligrams per 100 g of cooked meat basis, the 80 degrees C baked patties had the highest CLA concentration (152 mg/100 g of meat), while baked patties cooked to 60 degrees C contained the greatest concentration of CLA on a per patty basis (113 mg of CLA/patty). During storage, cooked beef oxidized rapidly as measured by thiobarbituric reactive substances. However, oxidation did not affect CLA concentrations.