Mechanism of heat-induced gelation for ovalbumin under acidic conditions and the effect of peptides

Abstract

The mechanism of the heat-induced gelation of ovalbumin (OVA) under acidic conditions and the effect of amphiphilic peptide additives on gelation were investigated using dynamic light scattering (DLS) and small-angle neutron scattering (SANS). This combination of techniques provides structural details spanning a wide range of length scales, from micrometer (DLS) to nanometer (SANS). The molecular morphology and structure probed by SANS suggest that the heat-induced gelation of OVA solution forms a phase-separated structure. The addition of an amphiphilic peptide to the system drastically changed the aggregated structure by promoting the formation of OVA clusters. Furthermore, heating of the solution of OVA and the peptide resulted in effective distribution of the peptide in the matrix of the heat-induced OVA gels and endowed the gel with increased strength. This simplistic approach to increase the gel strength can be applied to any protein/peptide gel system to impart the gel system with specific physical properties required by their intended application. The mechanism of the heat-induced gelation of ovalbumin (OVA) under acidic conditions and the effect of amphiphilic peptide additives on gelation were investigated using dynamic light scattering (DLS) and small-angle neutron scattering (SANS). The molecular morphology and structure probed by DLS and SANS suggest that the heat-induced gelation of OVA solution forms a phase-separated structure. Heating of the solution of OVA and the peptide resulted in effective distribution of the peptide in the matrix of the heat-induced OVA gels and endowed the gel with increased strength.