BIOCHEMISTRY OF LEAN MUSCLE TISSUE AS RELATED TO WATER-HOLDING CAPACITY

Authors: VAN LAACK RIETTE - 1280-15-00; Solomon, Morse

Submitted to: American Meat Science Association Conference Reciprocal Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 8/24/1994
Publication Date: N/A
Citation: N/A

Interpretive Summary: Waterholding capacity (WHC) may be defined as the ability of meat to retain its own water despite the application of force. In fresh meat WHC is expressed as drip loss during storage. Meat with a high WHC has minimal drip loss. WHC affects the weight loss and the appearance of meat. Drip losses also imply loss of protein and affect sensory quality of meat. Thus, WHC will affect the financial value of meat. Information on the mechanisms responsible for drip formation will provide better means of controlling and predicting WHC. Research on the processes determining WHC of meat is discussed. Waterholding capacity of meat is mainly determined by lateral shrinkage of the muscle structure. Several factors affect this shrinkage, the main factor being denaturation of the myofibrillar protein myosin. Myosin denaturation is determined by post mortem pH and temperature-decline, and the onset of rigor. A model including these factors provides a theoretical explanation for the fact that rapid chillin does not always result in an increase in WHC. Although there is a correlation between denaturation of sarcoplasmic proteins and drip loss, it seems unlikely that denaturation of sarcoplasmic proteins is involved in WHC of meat. The knowledge of the importance of myosin denaturation and rigor for drip formation may be used in development of equipment to predict and select meat with a specific WHC.

Technical Abstract: Water-holding capacity (WHC) may be defined as the ability of meat to retain its own water despite the application of force. In fresh meat WHC is expressed as drip loss during storage. WHC is important as it affects the financial value of meat. Information on the mechanisms responsible for drip formation will provide better means of controlling and predicting WHC. .Research on the processes determining WHC of meat is discussed. Water- holding capacity of meat is mainly determined by lateral shrinkage of the muscle structure. Several factors affect this shrinkage, the main factor being denaturation of the myofibrillar protein myosin. Myosin denaturation is determined by postmortem pH and temperature-decline, and the onset of rigor. A model including these factors provides a theoretical explanation for the fact that rapid chilling does not always result in an increase in WHC. Although there is a correlation between denaturation of sarcoplasmic proteins and drip loss, it seems unlikely that denaturation of sarcoplasmi proteins is involved in WHC of meat. Sarcomere length, ion concentration, ageing and osmotic pressure have been implicated in WHC. Knowledge of the importance of these factors is rather limited. The knowledge of the importance of myosin denaturation and rigor for drip formation may be used in development of equipment to predict and select meat with a specific WHC.