Research On Preparation And Adsorption Application Of Potato Porous Starch

Natural starch is safe and biodegradable but with weak adsorption capacity.Therefore,the preparation of porous starch with higher specific surface area and pore volume is the focus of current research.In this study,potato starch was used as the raw material to obtain porous starch through the optimized solvent exchange method.Scanning electron microscope(SEM),Fourier transform infrared spectroscopy(FT-IR),nuclear magnetic resonance(NMR),X-ray diffraction pattern(XRD)and thermogravimetric(TG)methods were used to characterize and analyze the prepared porous starch,and the adsorption effect of curcumin,vanillin and zinc were evaluated.Here shows the major findings of this study:1.After the potato starch was gelatinized at high temperature(90 °C)and cooled at 5 °C for 48 h,porous starch can be prepared by the solvent exchange method.The optimal preparation conditions are selected based on the oil absorption rate,methylene blue adsorption rate,and gas adsorption amount.The best reaction conditions are as follows: The starch slurry concentration is 0.15 g / m L,ethanol: acetone is 10: 0,exchange time is 1h.The porous starch prepared under this condition has a BET of 35.52 m2 / g,pore size distribution of 3.1-44.5 nm,and belongs to mesoporous starch.2.The characteristics of the porous starch prepared in the experiment were characterized by SEM,FT-IR,NMR,XRD and TG.SEM intuitively confirmed that porous starch could be obtained by different treatment processes.The pore distribution of macroporous starch was wide but uneven,and mesoporous starch could form a richer and more uniform porous structure;FT-IR and NMR showed that the porous starch did not produce new functional groups,indicating that the experimental selection method was physical denaturation;XRD analysis showed that the experimentally prepared macroporous starch and mesoporous starch had no characteristic diffraction peaks,indicating that the crystal structure of starch was completely destroyed after solvent exchange treatment;TG showed that porous starch had the same thermal stability as natural starch.3.The adsorption of curcumin by macroporous starch was chemical adsorption.When the weight ratio of curcumin to macroporous starch is 0.4%,the maximum adsorption capacity(3.67 mg / g)can be reached.After adsorption,the sample was light yellow,the water solubility was significantly improved,most of the antioxidant ability was preserved,and in vitro simulated gastric fluid(SGF)and intestinal fluid(SIF)experiments showed that it demonstrated a slow-release effect..4.In this study,we compared the effect of macroporous starch(SPS)prepared by solvent method(SPS)or enzymatic hydrolysis method(EPS)on micro-encapsulation of vanillin under freeze drying and oven drying methods.The adsorption capacity of natural starch was weak,but the SPS + VA prepared by freeze-drying technology had better adsorption capacity of vanillin and better thermal stability.FT-IR analysis confirmed that the adsorption of vanillin by macroporous starch appeared as physical adsorption.5.The mesoporous starch and zinc salt form a complex,and the amount of zinc adsorption could reach 1121 mg / L.The formation of the complex was a physical adsorption process.The ?H value of the inclusion compound was decreased and the conductivity value was increased.In summary,after starch gelatinization,porous starch can be prepared by the solvent method,and cooling starch gel can obtain better pore density and specific surface area than freezing method;different treatment processes can produce porous with different pore size and specific surface area Starch;the porous starch prepared by the solvent method is physically denatured,and the crystal form of the starch is destroyed;The adsorption of curcumin by macroporous starch enhances the water solubility of the composite.when the macroporous starch adsorbs vanillin and the mesoporous starch adsorbs zinc,it showed the compound had better thermal stability.