Effects of High Hydrostatic Pressure on the Solubility and Molecular Structure of Rice Protein

The effects of high hydrostatic pressure(HHP)treatment at 100-500MPa for 10-30min on the solubility and molecular structure characteristics of thermal denatured rice protein dissolved in solvent A(water solution,pH 8.0)and solvent B(containing 6mol/L urea and 1% mercaptoethanol,pH 8.0)were researched.The results showed that the solubility of rice protein in solvent B was notably improved after HHP treatment,especially at 100MPa for 20min,which was from 6.89%at 0.1MPa up to 18.13%,while in solvent A,it was from 4.37%to 9.60%at the same pressure condition.SDSPAGE analysis showed that the subunit composition of soluble protein treated under HHP in solvent A had few differences from that of untreated.The similar phenomena could be seen in insoluble protein.However in solvent B,the relative contents of the subunits in soluble changed obviously.The observation of SEM(Scanning Electron Microscope)showed that the surface structure and aggregation state of rice protein could be changed by HHP treatment.