Development and characterization of high internal phase pickering emulsions stabilized by heat-induced electrostatic complexes particles: Growth nucleation mechanism and interface architecture

In this work, the heat-induced ovalbumin (OVA)-pectin (PE) electrostatic complex particles (HIECP) prepared by different heating sequences (type I particles (I): Heat-treated ovalbumin/pectin complexes at pH 4; type II particles (II): Complexes between pre-heated ovalbumin and pectin at pH 4) and biopolymer ratios were used as stabilizers to form high internal phase Pickering emulsions (HIPPEs). The results showed that I had a more compact structure, higher net surface charge, and smaller particle size than II, due to the different growth nucleation mechanism. II-stabilized HIPPEs exhibited a smaller oil droplet size, stronger gel structure, and better stability than I-stabilized HIPPEs, owing to their suitable wettability, rigid core-shell structure, and robust and dense interface architecture. Moreover, the stability and gel-like structure of HIECP-stabilized HIPPEs improved with increasing PE content due to steric barrier and thickening effects. Our findings provide a new perspective for understanding heat-induced biopolymer particles as effective Pickering stabilizers.

Automated summary

This study prepared heat-induced ovalbumin-pectin electrostatic complex particles and used them as stabilizers to form high internal phase Pickering emulsions. The results showed that the heating sequence and biopolymer ratio had significant effects on the particle structure and emulsion stability.