Relationship of changes in quality attributes and protein solubility of ground beef under pasteurization conditions

Cook loss and shrinkage are important parameters for evaluating quality attributes of processed meats with the most important determinant being the thermal stability of proteins in the muscle tissue. In this study, we found that these attributes correlated with a loss of soluble sarcoplasmic proteins (SSP) and soluble myofibrillar proteins (SMP) in ground beef patties during pasteurization (65-90 °C, 1-60 min). Cook loss in beef patties was linearly correlated with the area shrinkage (R2 = 0.95), and with the loss of SSP (R2 = 0.87), SMP (R2 = 0.85), and total soluble proteins (TSP; R2 = 0.89). About 60-80% of SSP and SMP were rapidly lost in the first 2-5 min of heating, then decreased at lower rate until reaching an equilibrium value of approximately 22% of SSP and 20% of SMP of their initial values. Cook loss (29-35%) and area shrinkage (19-28%) also occurred rapidly in the first 2-5 min of heating. The concentration of TSP in exudate decreased, but the net weight of TSP and percentage of TSP (2-10%) lost in the exudate increased with heating time while the sum of TSP in exudate and meat decreased.