Injection of conjugated linoleic acid into beef strip loins

Beef strip loins (IMPS 180; n = 15) were sectioned in thirds and sections (n = 45) were left untreated (CNT) or injected with either a commercial powder conjugated linoleic acid (CLA) source (Powder) or a commercial oil CLA source (Oil), whose major isomers were 18:2cis-9, trans-11 and 18:2trans-10, cis-12 CLA isomers. Fresh Oil steaks had 3.20 and 3.15, Powder steaks had 4.67 and 4.62, and CNT steaks had 0.19 and 0.02 mg/g muscle tissue (wet basis) of the cis-9, trans-11 and trans-10, cis-12 CLA isomers, respectively. TBARS were similar (Oil) and lower (Powder), compared to CNT. Powder steaks had similar instrumental color, and beef and off flavor characteristics as CNT. Artificial marbling was created with Oil steaks having USDA Small79 and Powder steaks having USDA Modest86 marbling scores, while CNT steaks had USDA Slight94 marbling scores. Injection of CLA can be effective in significantly increasing CLA and potentially creating artificial marbling.