The incorporation of dehydrated rosemary leaves in the rations of turkeys and their impact on the oxidative stability of the produced raw and cooked meat

Thirty-six 12-week-old turkeys were distributed into six groups and were raised for 4 weeks on rations containing 0%, 0.5% or 1.0% dehydrated rosemary leaves as antioxidant in the presence of alpha-tocopheryl acetate from 10 to 300 mg/kg. Following slaughtering, breast and thigh meat samples, raw or cooked, from all six groups were collected to be refrigerated at 4 degrees C for 9 days. All stored samples were submitted to analysis for their concentration in malondialdehyde ( MDA), a lipid oxidation marker, and alpha-tocopherol. The results showed that the rations containing 300 mg/kg a-tocopheryl acetate increased the mean alpha-tocopherol content of the breast and thigh significantly ( P < 0.05) compared with the respective control values. No significant ( P > 0.05) changes could be observed in the alpha-tocopherol content of breast and thigh of turkeys consuming rations containing up to 1% dehydrated rosemary leaves. The refrigeration of the meats led to spontaneous increase in the MDA content of the breast and thigh meat samples. Samples from turkeys fed rations containing 300 mg/kg alpha-tocopheryl acetate showed the lowest mean levels of MDA after the 9-day refrigerated period. The incorporation of rosemary in the rations led to a modest decrease in the formation of MDA in the meats compared with the respective mean control values. The combination of alpha-tocopheryl acetate and rosemary was not associated with an additional decrease in MDA formation.