Water-binding capacity of myofibrillar proteins as influenced by sarcoplasmic protein extracts from normal and pale, soft, and exudative pork

Water retention is one determining factor in pork quality. The poor water-binding capacity (WBC) of Pale, Soft, and Exudative (PSE) pork has been associated with denaturation of sarcoplasmic and myofibrillar proteins. This study was conducted to determine the relevance of (denaturation of) sarcoplasmic proteins for WBC. PSE and normal myofibrils were combined with either sarcoplasmic extract from either PSE or normal samples. In addition, protein-free extracts from PSE and normal meat were combined with myofibrils from PSE and normal samples. The WBC of myofibrils combined with the sarcoplasmic extract from normal meat was significantly (P<0.05) higher than the WBC of myofibrils combined with sarcoplasmic extract from PSE meat. There was no difference between the WBC of myofibrils combined with the protein-free extracts from PSE and normal meat. It was concluded that the denatured sarcoplasmic proteins of PSE meat are not available to have a positive effect on the WBC of myofibrillar proteins. Results of this study provide an explanation for the low WBC of Red, Soft, and Exudative (RSE) pork.