Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 19, 2013
Publication Date: July 22, 2013
Citation: Bowker, B.C., Zhuang, H. 2013. Role of protein solubility in water-holding capacity of broiler breast meat [abstract]. Poultry Science Association Meeting Abstract. 92:169. Technical Abstract: The role muscle protein denaturation plays in determining water-holding capacity (WHC) in broiler breast meat is not well understood. Alterations in muscle protein solubility due to postmortem pH and temperature decline can be used as indicators of protein denaturation. In order to determine the influence of muscle protein denaturation on meat quality traits, this study measured muscle protein solubility at different times postmortem in breast fillets with high and low WHC. Deboned broiler breast fillets (n=72) were obtained from a commercial processing plant at 2 h postmortem and segregated into two groups (low-WHC, high-WHC) based on muscle pH and lightness values (L*). Moisture content, pH, and drip loss were measured at 24 h postmortem. Muscle samples were taken at 6 and 24 h postmortem for measuring salt-induced water uptake, cook loss, and protein solubility. Low-WHC fillets had higher (p<0.0001) drip loss (2.39% vs. 0.47%) and lower (p<0.0001) ultimate pH (5.83 vs. 6.20) than high-WHC fillets. At both 6 and 24 h postmortem, salt-induced water uptake was higher (p<0.0001) and cook loss was lower (p<0.001) in high-WHC fillets compared to low-WHC fillets. Salt-induced water uptake in 24 h samples was greater (p<0.01) than in 6 h samples. Cook loss was not different between 6 and 24 h samples. No differences in total protein solubility were observed between low-WHC and high-WHC fillets or at different times postmortem. Sarcoplasmic protein solubility was greater (p<0.05) in high-WHC fillets than low-WHC fillets. In both groups, sarcoplasmic protein solubility increased (p<0.01) between 6 and 24 h postmortem. Myofibrillar protein solubility decreased (p<0.01) from 6 to 24 h postmortem in both low-WHC and high-WHC fillets, but was not different between the groups. Overall WHC measurements in this study were not closely associated with differences in protein solubility. Results suggest that differences in postmortem protein denaturation, particularly of myofibrillar proteins, are not the primary source of WHC variation in broiler breast fillets.