Contact
    Start Publications Interfacial film formation and film stability of high ...
    ←  Publication Finder
    KSV NIMA

    Interfacial film formation and film stability of high hydrostatic pressure-treated beta-lactoglobulin

    Year: 2021

    Journal: Food Hydrocolloids, Volume 119, OCT

    Authors: Kieserling, Helena; Alsmeier, Ingalisa M.; Steffen-Heins, Anja; Keppler, Julia K.; Sevenich, Robert; Rauh, Cornelia; Wagemans, Anja Maria; Drusch, Stephan

    Organizations: German Research Foundation

    Keywords: Interfacial stabilization process; Oil/water-interface; Protein structure analysis; Electron paramagnetic resonance spectroscopy; Interfacial rheology; High pressure processing

    The mechanical stability of interfacial protein films is limited through the intermolecular interaction of the adsorbed proteins. Since the intermolecular interactions vary in dependence of the protein structure, the investigation of intentionally induced structural modifications (i.e., through high hydrostatic pressure) of interfacial active proteins is required to mechanistically understand their structure-function-relationship. The aim of this study was to link the structural analysis of pressure-treated whey protein beta-lactoglobulin at the oil/water-interface with the formation of the interfacial protein film and the resulting film stability against mechanical stress. For this purpose, we treated beta-lactoglobulin in water at pH 7 with hydrostatic pressures of 600 MPa for 10 min at 20 degrees C and analyzed the protein structure in oil/water-emulsion with Fourier-transforminfrared-spectroscopy, extrinsic fluorescence, and zeta-potential. We characterized the molecular density and interfacial film properties via Langmuir trough analysis, electron-paramagnetic-resonance-spectroscopy, interfacial shear and dilatational rheology. The structural flexibility of pressure-treated beta-lactoglobulin favored its unfolding and a fast interfacial protein film formation that resulted in pronounced intermolecular interactions, including van der Waals interactions, hydrophobic associations and disulfide bonds. The high interfacial molecule density combined with many and strong intermolecular interactions stabilized the pressure-treated protein film against shear deformation and small dilatational deformation. However, against high dilatational deformation, the pressure-treated beta-lactoglobulin film showed a lower stability due to a slow migration towards unoccupied interfacial area. Hence, our research contributes to the control of the mechanical protein film stability, and thus the colloidal stability of emulsions in dependence of the protein structure at the oil/water-interface.
    View publication