Abstract:In this study, quinoa starch was extracted from quinoa seeds by alkali method, and the extracted starch was modified by octenyl succnic anhydride (OSA), then the starch octenylsuccinate (OSA starch) was obtained. The structure and morphology of the native starch and OSA starch granules were compared by Fourier transform infrared spectroscope and scanning electron microscope. It was found that the OSA group was successfully attached to the surface of the starch, and the Particle surface was slightly damaged. And the effects of starch substitution degree, particle concentration and oil fraction on emulsion emulsification were analyzed by emulsion microstructure, droplet size and emulsifying index (EI). The results showed that the droplet size decreases with the increase of OSA starch substitution or starch granule concentration, and the EI value increases with the increase of OSA starch substitution degree or starch granule concentration, and the emulsion emulsifying properties is enhanced. As the oil fraction raise, the droplet size appears to increase, and within the range of the amount of OSA added by the food additive, the EI value of the OSA starch granule with substitution degree of 1.43% reaches a maximum of 75.48%, emulsifying properties were the best. These findings demonstrated that OSA modified quinoa starch can be used as a particle to stable Pickering emulsions and have great potential applications in food.
