Effect of age and different doses of dietary vitamin E on breast meat qualitative characteristics of finishing broilers

The supplementation of vitamin E on broiler chicken diets is essential to the prevention of lipid oxidation reactions in the meat and improvement of meat quality. The objective of this study was to assess the effect of different doses of dietary vitamin E on breast meat quality of broiler chickens in the finishing period. Five doses of vitamin E were used (30, 90, 150, 210, and 270 mg/kg feed) in broilers' diets from 42 to 54 d of age. A completely randomized design was conducted, followed by a split-plot, where the vitamin E dose was considered as the whole plot, and broilers’ age at slaughter was the subplot. Breast meat quality was assessed at 4 different ages (45, 48, 51, and 54 d old), using 50 birds per age, totaling 200 birds. Meat quality characteristics evaluated were: pH at 24 h post mortem, color (brightness, redness, and yellowness), water holding capacity, cooking loss, shear force, and lipid peroxidation. There was no interaction between age and dose of vitamin E for meat quality characteristics (P > 0.05). The age at slaughter had a quadratic effect (P < 0.05) on pH, brightness, redness, and water holding capacity. Although pH values were higher in the breast meat of older birds (51 and 52 d old), breast meat of younger birds (48 d) had a more reddish aspect. Shear force value was higher in breast meat of birds slaughtered at later ages (P < 0.01), as a linear age-effect was observed. Brightness increased linearly (P < 0.05) with higher vitamin doses, whereas treatments did not alter yellowness, cooking loss, and lipid peroxidation. In this study, increasing vitamin E doses in the finishing period increased the brightness of broiler breast meat, whereas slaughtering at later ages resulted in greater meat pH and shear force value.