Abstract:In this study, rice starch was used as raw material to prepare octenyl succinic anhydride(OSA) modified starch. The sunflower seed oil was used as oil phase, OSA hydrophobically modified starch and 5 kinds of anionic emulsifiers were used to build oil-in-water Pickering emulsions. The physical stability of the emulsion was studied by determining the emulsion volumes, droplet size distributions and microstructure. The results showed that when the emulsifier concentration was 1.0 wt. %, the emulsion stabilized by hydrophobic starch/anionic emulsifier had better physical stability than the emulsion stabilized only by starch particles. When the ratio of starch and xanthan gum was 3︰1, the emulsion had the best stability and the smallest droplet size, which was 83.01 μm. When the ratio of starch and sodium carboxymethyl cellulose was 4︰1, the emulsion had the best stability and the smallest droplet size, which was 76.29 μm. The laser confocal scanning microscope result showed that when the hydrophobic starch particles were used in combination with anionic emulsifiers, the starch particles were adsorbed on the oil-water interface and present a mechanical barrier, which increased the stability of the emulsion.