Ultrasonic-assisted Preparation Of Starch Microcrystals And Its Adsorption On Curcumin

Corn is widely planted in China and its yield is huge.However,the added value of corn starch is low and its use is limited.Therefore,it is urgent to increase the added value by expanding the application field.Starch microcrystalline was prepared by using ultrasonic assisted hydrolysis of acid alcohol and corn starch as raw material.The effects of hydrolysis time,hydrolysis temperature,ethanol concentration and hydrochloric acid concentration on the preparation of starch microcrystalline were studied by single factor and response surface experiments;At the same time,starch structure change was further analyzed by using X-ray diffraction,scanning electron microscopy,differential scanning calorimetry to provide a reference for the use of corn starch.In this study,starch microcrystalline was prepared by using ultrasonic assisted hydrolysis of acid alcohol first to examine the hydrochloric acid concentration,hydrolysis time and hydrolysis temperature,ethanol concentration on the adsorption of curcumin.three optimal levels of the single factor were selected respectively and analyzed in response surface,and the optimized process parameters are: concentration of hydrochloric acid 2.2 mol/L,60% ethanol concentration,temperature of 51?,the time 69.5 h,and the preparation of starch microcrystalline adsorption amount of curcumin 2.422 mg/g.The time and power of ultrasonic wave were tested by single factor test,and it was found that when the power was 200 W and the ultrasonic time was 30 min.It played a good auxiliary role in the preparation of starch microcrystalline.Secondly,The microstructure and properties of starch microcrystalline were analyzed by means of modern analysis.In the electron microscope observation,it was found that the surface of the original starch granule was smooth and smooth,and the whole starch microcrystal presented irregular shape.The surface is rough and porous;Under Differential Scanning Calorimetry of the heat meter,it was found that the hydrolysis process of starch microcrystalline was rapid in the non-crystallization zone,and then the crystalline region hydrolysis rate increased;X-ray diffraction showed that the grain type of starch microcrystalline was the same as that of corn starch and the crystallinity of starch microcrystalline under optimum condition was 50.59%.Finally,after testing the storage properties of curcumin by microcrystalline starch,it found that microcrystalline starch in light conditions,avoid light,20?30?40?50?60 ?storage conditions,the contents of curcumin in 20 day are: 0.479?0.615?1.120?0.623?0.534?0.420?0.313 mg/g respectively;Starch microcrystalline in light conditions,20?30?40?50?60 storage ?conditions,the contents of curcumin in 20 day are: 0.258?0.360?0.290? 0.234?0.233?0.197?0.182 mg/g respectively.Due to its special surface structure,the storage performance of starch microcrystalline is obviously better than that of original starch.In this study,the preparation conditions of starch microcrystals and their storage properties for curcumin were explored,which provided a theoretical basis for the diversified utilization of maize.