High-pressure homogenization assisted pH-shifting modified soybean lipophilic protein interacting with chitosan hydrochloride: Double emulsion construction, physicochemical properties, stability, and in vitro digestion analysis

This study was aimed to improve ability of soybean lipophilic protein (LP) to stabilize W/O/W emulsions. LP modified through high-pressure homogenization assisted pH-shifting, then modified LP-chitosan hydrochloride (MLP-CHC) complexes were prepared, which used stabilize W/O/W emulsions. Multispectral techniques unveiled that high-pressure homogenization assisted pH-shifting attenuated vibrational frequency of N-H in LP and expose more hydrophobic residues. According to molecular docking, MLP and CHC formed covalent complexes through electrostatic attraction and improved ability to stabilize the interface. The W/O/W emulsion using high-pressure homogenization assisted base-shifting LP (11LP) had a smaller particle size (9.96 mu m), higher absolute potential (46.96 mV) and interfacial adsorbed protein (67.02%). Meanwhile, MLP-CHC complexes allowed the W/O/W emulsion to form stronger network structure and exhibit stronger stability in acidic, alkaline, thermal and high ionic concentration environments. The in vitro digestion showed that W/O/W emulsion could effectively protect the bioactivity of vitamin B-12 and vitamin E during the digestion process, and realize their efficient delivery. This study offers theoretical reference for constructing of protein-polysaccharide-based functional emulsion transport systems for food industry.