Heat-modulated conformational changes of soy hull polysaccharide and their impact on the oil-water interface...

This study investigated the effect of thermally induced conformational transitions on the behavior of soy hull polysaccharide (SHP) at oil-water interface. As preheating temperature increased from 50 °C to 90 °C, progressive droplet flocculation occurred, though emulsions remained stable, with maximal flocculation at 90 °C driven by conformational rearrangements. Atomic force microscopy (AFM) revealed morphological transitions from spherical/compact assemblies (50-60 °C) to irregular aggregates (70-90 °C), accompanied by reduced interfacial adsorption, network disruption, and decreased viscosity. Specifically, when SHP were preheated from 50 °C to 60 °C, most polysaccharides chains contracted toward the droplet core, producing a fried-egg-like shape at the interface. However, at 70-90 °C, the absence of a core led to a disordered, loosely organized interfacial structure with a noticeable preference for the aqueous phase. The findings highlight the pivotal role of temperature-induced conformational transitions in modulating interfacial dynamics and offer new mechanistic insights into the stabilization of emulsions.