The effect of pH and heating on the aggregation behavior and gel properties of beef myosin

Effects of pH and heating on the structure, aggregation, and gelation of beef myosin were evaluated. The results of the changed fluorescence intensity and decreased α-helix content of all treatments demonstrated that protein structure unwound with pH and temperature. Differential scanning calorimeter (DSC) data also proved that protein head denaturation and tail denaturation occurred at 55 °C and 75 °C, respectively. The increment of hydrophobicity and the reduction of sulfhydryl group content indicated that hydrophobic interactions and disulfide bonds were beneficial to protein aggregation at 55 °C. Significantly, the content of active sulfhydryl at pH 6.0 reached its lowest value (15.61 ± 0.67 μmol/g) at 85 °C. In addition, beef myosin aggregation was corroborated by the decreased solubility and increased turbidity of all treatments. The great three-dimensional network structure could be formed at pH 6.0 above 75 °C.