Solubilization of concentrated protein dispersion: Effect of hydrogen peroxide (H2O2) and sodium hexametaphosphate (SHMP)

In the present study, the functionality of H2O2 and sodium hexametaphosphate (SHMP) on solubilization of whey protein hydrolysate (WPH) and isolate (WPI), resistant to sterilization temperature at various concentrations, was investigated. The physical state of the treated WPH and WPI dispersions at the presence of various con-centrations of H2O2 and SHMP was related to their colloidal structures and thermal stability. Using optimum concentration of H2O2, both dispersions stabilized against heat treatment likely because free SH groups blocked by H2O2. The solubilization range by SHMP was comparably low (up to 6 and 15% w/w for WPI and WPH, respectively). Moreover, the desirable stability was reached when H2O2 and SHMP were simultaneously used. The pH adjustment (7.2), prior to sterilization, also improved the stability range. This research highlights the potential of these substances to restrain the denaturation of whey proteins. Further investigations are still required to elucidate the accurate mechanism of solubilization.