The modification of ovalbumin surface properties treated by pulsed electric field combined with divalent metal ions

Abstract To explore the protein surface properties treated by Pulsed Electric Field (PEF) with metal ions, we employed ovalbumin as the object and added three divalent metal ions (Ca 2+ , Cu 2+ and Ba 2+ ), respectively. The changes in surface hydrophobicity and surface tension were evaluated. Raman, FTIR, and fluorescence were used to record their structure variations. The results show that the surface hydrophobicity and surface tension of ovalbumin increased with the adding of metal ions. It was caused by the burial of some hydrophobic residues and variation of hydrophobic interaction between molecules, which was consistent with the results of spectra. With the combination of metal ions and PEF, the surface hydrophobicity and surface tension of ovalbumin showed an enhanced trend at first and then reduced with pulse time. These results demonstrate that metal ions and PEF have crucial influences on surface properties, that might afford a theoretical basis for the production and application of ovalbumin.