Insight into the mechanism of textural deterioration of myofibrillar protein gels at high temperature conditions

The present study aimed to illuminate the mechanism of textural deterioration of MP gels induced by high temperature treatments (75-95 °C, 20 min). Measurements of textural properties showed that the decreased thermal stability is responsible for the gel texture. Analysis of the microstructure of MP gel showed that the over-aggregation of MP was strictly related to the gel quality loss. Further investigations on protein structures indicated that the proteins tended to be more stretched in higher temperature treatments, leading to an increase in disulfide bonds and a reduction in the noncovalent interactions, promoting the over-aggregation of protein. To conclude, high temperature-induced textural deterioration of MP gel was initialized by the dramatic changes of protein structures during heat treatment, which decreased thermal stability of MP gels due to the over-aggregation of MP molecules. Once the altered thermal stability was insufficient to resist the over-heating, such deterioration would occur.