Effect of different postmortem ageing conditions on physicochemical properties, structure and water-holding capacity of pork

This study aimed to determine the effects of postmortem ageing temperatures on protein-water interactions and muscle water-holding capacity (WHC) of pork. The oxidation degree, solubility and secondary structure of myofibrillar protein (MP) were also studied. Porcine longissimus lumborum muscles were aged at -6 +/- 1, 4 +/- 1, and 10 +/- 1 degrees C for 3, 12, 24, 72, 120 and 168 h, respectively. The results showed the lower ageing temperature is conducive to decrease the protein oxidation and the transformation of protein conformation from ordered structures (alpha-helices and beta-sheets) to disordered structures (beta-turns and random coils). These physicochemical changes favoured protein-water interactions, thus the muscle samples aged at -6 +/- 1 degrees C for 120 h had the highest protein solubility and WHC. This work revealed that ageing at sub-freezing temperature (-6 +/- 1 degrees C) is beneficial to reduce protein oxidation and improve muscle water-holding capacity.