Titration of fresh meat color stability and malondialdehyde development with Holstein steers fed vitamin...

Pigment and lipid oxidations were investigated in longissimus lumborum (LL), semimembranosus (SM), and gluteus medius (GM) from Holstein steers fed four doses of vitamin E (64 [control], 295, 550, or 2,173 IU/d) for two durations (42 or 126d). Vitamin E dose did not affect (P = .30) carcass quality or yield characteristics. The LL was stored in vacuum packages at 4 degrees C for 14, 28, and 56 d, and GM and SM were stored for 14 d. Increments of dose and duration of vitamin E supplementation increased (P < .001) alpha-tocopherol concentration in blood plasma and in these muscles. During simulated retail display, accumulations of metmyoglobin (METMB) and thiobarbituric acid reactive substances (TBARS) were greater (P < .01) in beef from control than in beef from supplemented steers. In cubic models, muscle alpha-tocopherol accounted for 79% of the variation in TBARS and 66% of the variation in METMB. Color display life, calculated by the METMB threshold method, revealed fewer dose and duration effects of vitamin E than were evident following analysis of variance of the METMB responses. Across durations and muscles, color display-life of fresh beef calculated by the METMB threshold method was extended (P < .05) .9 to 1.8 d by vitamin E supplementation (P < .05). Storage for 28 or 56 d caused only a slight decline (P < .001) in LL alpha-tocopherol concentration but diminished (P < .05) vitamin E effects on color display-life. Although the ranking of alpha-tocopherol accumulation was GM > SM > LL, the color display-life ranking of these muscles across vitamin E treatments was LL > SM > GM.