Modification Of Quinoa Starch By Heat-moisture Treatment With Hydrophobic Modification And Its Applications In Pickering Emulsion

Quinoa starch granules are small,so it can be used as granule emulsifier to stabilize food grade Pickering emulsion.However,the hydrophilicity of the surface of starch molecules is not involved in the formation of emulsions.It is necessary to carry out octenyl succinic acid(OSA)hydrophobicity.Slow-digested starch(SDS)is food with a low glycerin production index(GI).Long-term consumption can reduce postprandial insulin secretion and help prevent and treat metabolic syndrome such as diabetes and obesity.Heat-moisture treatment(HMT)is an effective way to form SDS,and OSA modified starch itself has slow digestion characteristics.In this paper,buckwheat starch was removed by the alkali method.The effects of these two treatment methods and modify order on the physicochemical properties of starch were studied by HMT and OSA alone and synergistic modification of the original starch,and the emulsification of these modified particles of Pickering emulsion.And the impact of storage stability.The effects of different moisture contents(15% ~ 30%)on the morphology of the heat-moisture treatment starch granules were analyzed by means of scanning electron microscopy,brabender viscosity analyzer and in vitro digestion,and the results showed that the higher moisture content,starch granules more likely to produce adhesion,agglomeration and other phenomena.The results of viscosity analysis show that with the increase of water content,the peak viscosity and termination viscosity decrease,the disintegrating value decreases,and the shear resistance of starch increases.The results of in vitro digestive analysis showed that the content of starch resistant starch was higher,the content of SDS increased first and then decreased with the increase of moisture content,and the best effect was achieved when the moisture content was 20%.Properties of sympathetically modified particles was studied by means of infrared spectrometer(FT-IR)and X-ray diffraction analyzer(XRD).Comparative study found that OSA modification has little effect on the morphology of starch granules.The wet heat treatment combined with OSA modification will cause slight adhesion of starch granules,but does not destroy its basic morphology.The results ofFT-IR showed that the succinic acid oriental group was successfully inserted into the starch molecule,and the proportion of the non-crystalline area of the sympathetically modified starch increased,and the proportion of the crystallization zone reduced.XRD results showed that the heat modification or OSA modification had no effect on the starch crystal form,and it was still A type structure.The crystallinity of buckwheat starch was less than that of the original starch after moist heat treatment.The results of in vitro digestion analysis showed that the slow-digested starch content of OS-HMT composite modified starch increased significantly.The stability of the emulsion stabilized by modified starch granules was examined by measuring the contact angle,surface tension and emulsification index.The results demonstrate that the modification of OSA reduces the surface tension of the particles,increases the contact angle,and has better surface activity.The wettability of starch granules after wet heat modification is basically the same as that of OSA modified starch.The surface tension of the particles has a considerable influence on the contact angle,and the inclusive particle characteristics of the OS-HMT sample are better than those of the HMT-OS.Synergistically modified particles exhibited better storage stability and better results with HMT-OS samples.Quinoa starch granules are small,so it can be used as granule emulsifier to stabilize food grade Pickering emulsion.However,the hydrophilicity of the surface of starch molecules is not involved in the formation of emulsions.It is necessary to carry out octenyl succinic acid(OSA)hydrophobicity.Modified.Slow-digested starch(SDS)is food with a low glycerin production index(GI).Long-term consumption can reduce postprandial insulin secretion and help prevent and treat metabolic syndrome such as diabetes and obesity.Wet heat treatment is an effective way to form SDS,and OSA modified starch itself has slow digestion characteristics.In this paper,buckwheat starch was removed by the alkali method.The effects of these two treatment methods and modify order on the physicochemical properties of starch were studied by HMT and OSA alone and synergistic modification of the original starch,and the emulsification of these modified particles of Pickering emulsion.And the impact of storage stability.The stability of the emulsion stabilized by modified starch granules was examined by measuring the contact angle,surface tension and emulsification index.The results demonstrate that the modification of OSA reduces the surface tension of the particles,increases the contact angle,and has better surface activity.Thewettability of starch granules after wet heat modification is basically the same as that of OSA modified starch.The surface tension of the particles has a considerable influence on the contact angle,and the inclusive particle characteristics of the OS-HMT sample are better than those of the HMT-OS.Synergistically modified particles exhibited better storage stability and better results with HMT-OS samples.