Meat quality of vitamin E enriched beef.

NASSU, R. T.; DUGAN, M. E. R.; JUÁREZ, M.; BASARAB, J. A.; BARON, V. S.; AALHUS, J. L.

Meat quality of vitamin E enriched beef.

Autores

Descripción

This study aimed to evaluate quality and sensory properties of 6 and 21 days aged beef (steaks and ground beef) from animals with different tissue levels of ?-tocopherol. A total of 56 feedlot steers were fed a barley-based finisher diet with four vitamin E supplementation levels (340, 690, 1040 and 1740 IU dl-?-tocopheryl acetate.animal-1.day-1) for 120 days. The animals were then grouped based on their ?-tocopherol (?g.g meat-1) levels (<3 or low; 3 to 4 or low-medium; 4 to 5 or high-medium and >5 or high). Longissimus lumborum muscle and overlying subcutaneous fat were aged 6 days and then used to prepare steaks and 75/25 ground beef. Steaks aged for 21 days were also analysed. Although the increase in fatty acid oxidation over time was smaller (P<0.001) in the high-medium and high groups, tissue ?-tocopherol levels did not affect (P>0.05) pH, proximate analysis, drip and cooking losses, and shear force of steaks. Similarly, ?-tocopherol tissue levels had no effect (P>0.05) on sensory characteristics of 6 days aged steaks and ground beef. No effect of tissue ?-tocopherol levels was found over the 6 days retail evaluation period for steaks, but with 21 days of ageing, a delay in formation of metmyoglobin (P=0.008) was observed with higher tissue levels of ?-tocopherol. Similar results were found for ground beef (25% fat) prepared from 6 days aged meat. Higher ?-tocopherol tissue levels protected ground beef ad long-aged steaks from discolouration and lipid oxidation.