Effect of dietary vitamin E supplementation on cholesterol oxidation in vacuum packaged cooked beef steaks

The effect of dietary vitamin E supplementation on cholesterol oxidation in vacuum packaged, cooked, refrigerated and frozen beef steaks, was investig ated. Steers (Friesian x Charolais x Black Hereford) were fed diets providi ng 20 or 3000 mg alpha-tocopheryl acetate/head/day for 135 days prior to sl aughter, alpha-Tocopherol concentrations in M. psoas major (PM) and M. long issimus dorsi (LD) were significantly (p < 0.05) increased by supplementati on and were significantly (p < 0.05) higher in PM than LD. Cholesterol oxid ation (monitored by measuring 7-ketocholesterol formation) increased during refrigerated and frozen storage in some, but not all, groups, and tended t o be higher in PM than LD. Dietary vitamin E did not affect 7-ketocholester ol formation in LD, but significantly (p < 0.05) reduced concentrations in PM during refrigerated and frozen storage. Supplementation significantly (p < 0.05) reduced TEARS in PM and LD, indicating that vitamin E improved oxi dative stability in both muscles. The results show that dietary vitamin E s upplementation inhibits cholesterol oxidation in vacuum packaged, cooked be ef during refrigerated and frozen storage, but may be influenced by muscle type. (C) 2000 Elsevier Science Ltd. All rights reserved.