Stabilizing emulsions using high-amylose maize starch treated by solvothermal process

Abstract

This paper proposes a method to modify high-amylose maize starch (HAMS) with lauric acid in an ethanol solvothermal system to prepare a cold-water swelling esterified starch (M-HAMS). Using M-HAMS as a granule stabilizer, oil-in-water Pickering emulsions were prepared, and factors affecting the oxidation stability of emulsion, such as granule content, oil-water ratio, pH value, and NaCl concentration, were studied. Atomic force microscopy (AFM) analysis showed that M-HAMS granules swell into dense molecular chains liking a three-dimensional network barrier in the emulsion, which increases the viscosity of continuous phase and prevents the oil droplets from contacting the pro-oxidant in the water phase, thus reducing the peroxide value. At the same time, the influence of changes in pH value and NaCl concentration on the viscosity and stability of emulsion is weakened. Therefore, the preparation of M-HAMS granule by ethanol solvothermal is a simple and effective method.