Molecular mechanisms of improving high internal phase emulsions stability of soy protein isolate and konjac glucomannan complexes fabricated with dynamic ultra-high pressure

Abstract

This study investigates the effectiveness and underlying mechanisms of dynamic ultra-high pressure (DUHP)-modified soy protein isolate (SPI) and konjac glucomannan (KGM) complexes in stabilizing high internal phase emulsions (HIPEs). The DUHP treatment of SPI enhanced its molecular structure, exposing hydrophobic amino acids that facilitated the formation of a stable non-covalent complex with KGM. The stability of these complexes primarily arises from the synergistic interactions of hydrogen bonds and van der Waals forces. The interaction between DUHP-treated SPI and KGM was significantly improved, leading to HIPEs stabilized by 0.4 % KGM exhibiting smaller droplet sizes and superior emulsifying properties. The enhanced interfacial adsorption capacity of these complexes enabled a more uniform and effective distribution at the oil-water interface, which significantly increased the viscoelasticity of the emulsion. This improvement helps to prevent droplet aggregation and merging while also enhancing thermal stability. Furthermore, the DUHP treatment promoted non-covalent interactions between SPI and KGM, enhancing the interfacial activity of the complexes and facilitating the formation of a robust three-dimensional network structure. This structural enhancement contributes to the overall stability of HIPEs. The findings of this study offer valuable insights into the use of DUHP technology as a means to improve the stability of HIPEs.