Abstract: In this study, wheat gluten nanoparticles and xanthan gum were used to synergistically stabilize Pickering emulsions and their physicochemical properties and microstructure were characterized. The results showed that stable Pickering emulsions could be prepared through the synergism between xanthan gum and wheat gluten nanoparticles. While low concentration of xanthan gum (0.2%) promoted creaming, the emulsion could be stored for one month at 4 ℃ without any aggregation or creaming when the concentration of xanthan gum was equal to or greater than 0.3%. When the concentration of xanthan gum was 1%, the emulsion became unstable after 30 days. The emulsion stability varied with different orders of emulsification. The M-WG-XG emulsion (prepared by sequential dispersion of a mixture of wheat gluten nanoparticles and corn oil, followed by addition of xanthan gum) had the highest stability and smallest particle size (21.4 ± 0.314) μm. The addition of xanthan gum increased the net charge and consequently stability of emulsions. The droplets were evenly distributed and the interface layer exhibited a multilayer structure under confocal laser scanning microscopy. Compared to the other emulsions, the M-WG-XG emulsion possessed a better viscoelasticity and higher salt stability (0–1 000 mmol/L NaCl) against aggregation.

Key words: wheat gluten nanoparticles, xanthan gum, Pickering emulsions, physicochemical properties