Inhibition of Lipid Oxidation in Chicken by Carnosine and Dietary α-Tocopherol Supplementation and its Determination by Derivative Spectrophotometry

Abstract

The antioxidant activity of carnosine in chicken meat, and its relationship to dietary α-tocopherol supplementation, was examined. Broiler chickens were fed diets containing 30 (basal) or 200 (supplemental) mg α-tocopherol acetate kg −1 feed for 6 weeks. Raw and cooked thigh meat patties containing carnosine (0–1·5%) were prepared. Lipid oxidation, during refrigerated storage under fluorescent light, was assessed by monitoring malonaldehyde formation, using the TBA assay and single wavelength (conventional) or first derivative spectrophotometry. In raw patties, added carnosine improved oxidative stability for up to 10 days of refrigerated storage. In cooked patties, the 1·5% carnosine level provided the best antioxidant protection during 7 days of storage. Carnosine (1·5%) was at least as effective as supplemental α-tocopherol in improving the oxidative stability of raw and cooked patties. The presence of both antioxidants had an additive effect on oxidative stability. Overall, the use of derivative spectrophotometry improved the specificity of the TBA assay for monitoring MDA formation in refrigerated meats.