Effect of dietary ram horn hydrolysate (RHH) on the pH and color characteristics of carcasses, breast fillets and drumsticks of broilers

This study was conducted to define the effects of ram horn hydrolysate (RHH) on the pH and color properties of carcasses and dissected products in broilers. Two-hundred and forty male broiler chicks (Ross-308) were fed with basal diets supplied with RHH for 4 wks. Chicks were allocated to four dietary treatments (H-0 , H-1 , H-2 and H-3 groups) in a completely randomized experimental design. Feed and water were offered ad libitum consumption and lightening was continuous throughout the experimental period. H 0 group was fed only the basal diet and given normal drinking water. Treatment groups were fed with basal diet plus a 1% (H-1), 2% (H-2), and 3% (H-3)-RHH-added water in place of normal drinking water to meet the daily water requirements of chickens from 1 to 28 days of ages. At the end of the trial all birds were slaughtered, then the ranges of pH and skin color of carcasses were determined at various times during the first 24 hour (1, 3, 7, 12, 17, and 24). After standard dissection of carcasses, breasts and drumsticks were divided into two groups for vacuum and aerobic packaging. Packed breasts and drumsticks were stored at 3 +/- 0.5 degrees C, for 12 days, and the color values were determined. The pH values of H-3 group were lower than those of H-0 , H-1 and H-2 groups (p <0.05). The lightness ( L*), redness ( a*) and yellowness ( b*) values increased during the 24-h period. The H-0 group had the higher b* values than those of RHH-added groups ( p < 0.05). The L*, a* and b* values of drumstick meats were higher than those of the breast meats ( p < 0.05). The values of b* in aerobic packaged breasts and drumsticks were higher than the vacuum packaged ( p < 0.05) treatments. The b* values increased with storage. The a* values of RHH-supplied groups were higher than that of the control ( p < 0.05), while b* value of control was higher than those of the RHH-supplemented groups ( p < 0.05). While the L* and b* values of drumstick skin were higher than that of drumstick meat, a* values in drumstick meats were higher ( p < 0.05). The vacuum packaging increased the a* value during storage. As a result, the use of RHH in broiler diets had a significant effect on the L*, a*, and b* values of carcasses and dissected tissue ( p < 0.01).