Preparation Of Octenyl Succinate Quinoa Starch Ester And Its Properties In Stabilized Pickering Emulsion

Quinoa starch has a small particle size and can be used as a solid particle emulsifier to construct food-grade Pickering emulsion.However,the hydrophilicity of starch molecules is not beneficial to the formation of stable emulsion,so it needs to be hydrophobic modified by octenylsuccinic acid(OSA).In this paper,quinoa starch as raw material,with alkali extraction quinoa starch,quinoa starch for OSA modification,to explore the modification of quinoa starch structure and physical and chemical properties.Then,the modified starch particles were applied to the preparation of Pickering emulsion to study the effects of starch substitution degree,particle concentration and oil-water ratio on emulsion emulsification and stability.With chitosan adsorption load finally beta carotene Pickering emulsion preparation of CS,emulsion,explore the CS-emulsion and emulsion in different physical and chemical condition of the original physical stability,freeze-thaw stability,thermal stability and oxidation stability(fat oxidation,etc.),and the two kinds of emulsion as carrier enhancement effect on the stability of beta carotene and slow release of beta carotene in the gastrointestinal tract.The main contents are as follows:After OSA modification,the degree of substitution of quinoa starch is 0.0104,0.0162,0.0224,0.0270.By Fourier infrared spectrum,scanning electron microscopy(sem),X-ray diffraction analysis,differential scanning calorimetry the starch granules were characterized,and the results show that symplectic alkenyl succinic acid groups successfully introduced to the quinoa starch molecular chains,reaction after the transparency of starch,gelatinization temperature,gelatinization enthalpy increased with the increase of the substitution degree is reduced,and solubility,emulsification and freeze-thaw stability increase with the increase of the degree of substitution.By measuring the surface tension,interfacial tension and contact Angle of starch particles,the stability of emulsion stabilized by modified starch particles was investigated.The results show that OSA modification can reduce the surface tension and interfacial tension of starch,increase the contact Angle,and increase the wettability of OSA starch,which has good emulsification performance and is beneficial to the preparation of stable Pickering emulsion.Within a certain range,the higher the starch particle substitution degree,particle concentration and oil-water ratio,the higher the viscosity,the better the emulsification and storage stability of the emulsion.In the Pickering emulsion experiments of chitosan adsorption on β-carotene,SEM,CLSM and potential change all proved that chitosan was successfully adsorbed on the surface of emulsion drops,and CS-emulsion was successfully prepared.Compared with the original emulsion,the CS-emulsion can significantly protect the stability of the emulsion under the conditions of freeze-thaw,heating and oxygen,and can significantly improve the thermal stability of β-carotene and its slowrelease effect in the gastrointestinal tract.This study provides a new idea for better embedding and delivery of active ingredients in emulsion.