| This article treated different concentrate and temperature peanut protein solution at different microfludization(HPM) pressure and different times, then studied the effect of microfludization on functional properties of peanut protein and mechanism of modification. The results indicates:1. We produced peanut protein isolate(PPI) from peanut protein concentrate in laboratory, then got the best technology parameter, and the produced PPI was used in the later stage study.2. Homogen times HPM treated circles did not affect the solubility, emulsibility and emulsive stability, foaming and foaming stability significantly, but the viscosity of PPI solution decreased slightly and tend to show the rheology characteristics of Newton fluids when treated with HPM twice and three times.3. Homogen pressure The solubility, foaming and foaming stability, the gelatinous strength of PPI solution increased linearly with HPM pressure in definite extent, but decreased when exceed the definite pressure; the emulsibility and emulsive stability of PPI solution increased slightly when treated with HPM, but did not change a lot all in all; the viscosity of PPI solution decreased when treated with HPM, some samples showed the rheology characteristics of Newton fluids; the thecal mechanical function of PPI treated with HPM decreased, too.4. Concentration HPM can improved the solubility, emulsibility and emulsive stability of PPI soluteon at low concentrateions, but the emulsibility and emulsive stability decreased at high concentrateions; and the foaming and foaming stability of PPI soluteion increased at low concentrateions, but the increasement was small when at high concentrations; HPM did not affect the viscosity of PPI soluteion at low concentrations, but the viscosity of PPI soluteion at high concentrations decreased when treated with HPM, and tended to showed the rheology characteristics of pseudoplastic fluids.5. Temperature There is no visible differences among PPI solution treated with HPM at different temperatures. The solubility, viscosity and rheology characteristics did not changed significantly at different temperatures; and temperature did not affect the emulsibility and emulsive stability, foaming and foaming stability notablly, but the pressure arrived maximal value changed.6. HPM effect on functional groups of peanut protein, the size and density of PPI treated with HPM decreased; the content of hydrosulfide group decreased with the HPM pressure increasing; the hydrophobicity and ultraviolet absorption residues increased linearly with the pressure; and the heat stability of HPM treated PPI increased.7. To study the HPM modification mechanism further, this article extracted arachin from the PPI solution treated with HPM, then analyzed the advanced structure of modified arachin to get the modification mechanism. The FT-IR spectrum results indicated, the content ofβ-plate sheet structure of arachin is far more than theα-helical structure, the absorption wavelength ofα-helical structure in amides III area all blue shift, andβ-plate sheet structure red shift. The analyze result of CD spectrum indicates, theα-helical structure andβ-corner of arachin treated with HPM decreased obviously, theβ-plate sheet structure and random coil structure creased obviously.8. To extend the application of mocrofluidization in food Industry, this article measured the safety of PPI treated with HPM, the results indicated, PPI treated with HPM did not affect the normal growth, activity information, food intake and outward appearance characteristic of mice, and the body increasement is similar to the control samples, no pathologyical change was found. So PPI treated with HPM is safe and has no side effect, this technology can extend to the food Industry. |
