Water-holding capacity of broiler breast muscle during the first 24 h postmortem.

Authors: Bowker, Brian; Zhuang, Hong

Submitted to: American Meat Science Association Conference Reciprocal Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 4/30/2013
Publication Date: 6/17/2013
Citation: Bowker, B.C., Zhuang, H. 2013. Water-holding capacity of broiler breast muscle during the first 24 h postmortem. Proceedings of the 66th Reciprocal Meat Conference. 74:34-35.

Interpretive Summary:

Technical Abstract: Water-holding capacity of poultry muscle influences both the sensory appeal for consumers and the product yield for processors. The underlying mechanisms that control water-holding capacity in poultry are not fully understood. The objective of this study was to determine the evolution of water-holding capacity and physicochemical traits in broiler breast fillets during the first 24 h postmortem. Carcasses (n=6) from 42-day old broilers were removed from a processing line immediately following evisceration and the right and left breast fillets (pectoralis major) were deboned and chilled in an ice slush for 45 min and then stored at 4°C until 24 h postmortem. Both the right and left fillets from each carcass were subdivided into three portions and designated for sampling at 0.75, 2, 4, 8, 12, or 24 h postmortem for determination of water-holding capacity (salt-induced water uptake and cook yield methods) and biochemical measurements. Data were analyzed in SAS using PROC MIXED with a model that included postmortem time as a fixed effect and carcass as a random effect. Both salt-induced water uptake (P<0.0001) and cook yield (P<0.0001) changed throughout the first 24 h postmortem in samples in a non-linear manner. Salt-induced water uptake increased from 0.75 to 4 h postmortem (38.0% to 54.1%), decreased from 4 to 8 h postmortem (54.1% to 31.4%), and then increased from 8 to 24 h postmortem (31.4% to 47.4%). Cook yield decreased from 0.75 to 4 h, increased from 4 to 12 h, and then decreased from 12 to 24 h postmortem. Muscle pH decreased (P<0.0001) from 6.51 at 0.75 h postmortem to 6.03 at 8 h postmortem. Muscle pH did not change from 8 to 24 h postmortem. Protein solubility was utilized as an indicator of muscle protein denaturation over the first 24 h postmortem. Both myofibrillar (P<0.01) and sarcoplasmic (P<0.001) protein solubility were influenced by postmortem time of sampling. Myofibrillar protein solubility values were not different between 0.75 and 2 h samples, but were lower by 4 h postmortem. Myofibrillar protein solubility did not change from 4 to 24 h postmortem. Sarcoplasmic protein solubility values were similar from 0.75 to 2 h postmortem but then increased through 24 h postmortem. Overall data show that water-holding capacity in broiler breast fillets fluctuates over the first 24 h postmortem. Data suggest that while alterations to muscle proteins and ultrastructure influence water-holding capacity, myosin denaturation does not explain changes in the water-holding capacity of broiler breast fillets.