Insight into the mechanism of gellan gum enhancing stability of high internal phase Pickering emulsions based on egg...

The integration of polysaccharides into high internal phase Pickering emulsions (HIPPEs) has been recognized as an innovative approach to improving their stability. To reveal the enhancing mechanisms of gellan gum (GG) on the stability of HIPPEs based on egg yolk granules (EYGs), this study systematically investigated the effect of GG concentration on the molecular structure, interfacial properties, and emulsion stability of EYGs-GG complexes. The results showed that HIPPEs stabilized by EYGs-0.3%GG complex exhibited the highest stability. In this complex, GG bound to the surface of EYGs particles via electrostatic attractions and hydrophobic interactions, leading to a 60.0% higher surface charge and a 59.2% lower surface hydrophobicity compared with those of EYGs particles. While the interaction reduced the penetration of EYGs particles at the oil-water interface, it increased the diffusion rate and molecular rearrangement behavior, facilitating the formation of the stable elastic interfacial film. Moreover, adding 0.3% GG formed denser 3D network structures in the aqueous phase, which inhibited oil droplet coalescence and further enhanced the structural strength of the HIPPEs. These findings provided theoretical insights into the mechanism by which GG enhanced the stability of emulsions based on EYGs, offering a rational design strategy for developing high-performance systems of HIPPEs.