Effects of inulin on the gel properties and molecular structure of porcine myosin: A underlying mechanisms study

The functional properties of myosin play a key role in the final quality characteristics of meat products. To explore the molecular mechanism of inulin in improving the properties of porcine myosin gel, different inulin concentrations (0%, 1%, 2%, 3%, 4%, and 5%) were added, and the gel water-holding capacity (WHC), microstructure, rheological properties, secondary structure, surface hydrophobicity and reactive sulfhydryl (RSH) contents were determined. The results showed that the inulin concentration was in the range of 0%-5%, there was a positive correlation with the gel strength, the storage modulus (G') and loss modulus (G '') of myosin also gradually increased with the increased of inulin concentration. The addition of inulin improved the WHC of myosin gel which was attributed to the formation of a fine microstructure, when the inulin concentration was 2%, the most significant improvement was observed. The improvement in the properties of heat-induced myosin gelation was due to the change in the molecular structure of myosin after the addition of inulin; the addition of inulin led to the transformation of the secondary structure of myosin, which resulted in the exposure of more hydrophobic groups and sulfhydryl groups than in the control and was conducive to the formation of a heatinduced dense myosin gel network. The principal component analysis results revealed the correlation between the gel properties and the molecular structure and provide a powerful tool for analysis. In conclusion, the addition of inulin can improve the functional properties of myosin and facilitate the heat-induced gelation of myosin.