油莎豆辛烯基琥珀酸淀粉酯的制备及结构表征

Preparationl and Characterization from Cyperus Esculentus L.Starches via Octenyl Succinylation

以油莎豆淀粉为原料,以辛烯基琥珀酸酐为酯化剂,选用水相法制备OSA淀粉酯。对不同OSA用量的油莎豆OSA淀粉酯的糊液透明度、冻融稳定性、抗性淀粉含量和接触角进行分析,通过傅里叶红外光谱、扫描电镜和X-射线衍射对淀粉酯结构进行表征。结果表明:油莎豆OSA淀粉酯取代度随OSA用量的增加而增大,反应效率与之相反。淀粉酯糊液透明度、冻融稳定性、抗性淀粉含量、接触角均随OSA用量的增加呈现上升趋势。傅里叶红外光谱表明淀粉酯在1732 cm-1和1558 cm-1出现酯羰基和羧酸的吸收峰。扫描电镜显示淀粉酯形态特征无明显变化,部分颗粒表面出现轻微腐蚀和裂纹。X-射线衍射分析证实,随酯化反应程度加深,淀粉酯部分晶体结构被破坏,淀粉相对结晶度下降。

In this paper,the starch of Cyperus Esculentus L.was used as the raw material,octenyl succinic anhydride(OSA)was used as the esterification agent,and the OSA starch ester was prepared by the aqueous phase method.The transparency and freeze-thaw stability of OSA starch ester paste,resistant starch content and contact angle of OSA starch ester of Cyperus Esculentus L.with different dosage of OSA were analyzed.The structure of starch esters was also characterized by Fourier transform infrared spectra,scanning electron microscopy and X-ray diffration.The results indicated that the substitution degree of OSA starch ester of Cyperus Esculentus L.increased with the increase of OSA dosage,but the reaction efficiency was opposite.The transparency and freeze-thaw stability of OSA starch ester paste,resistant starch content and contact angle of OSA starch ester of Cyperus Esculentus L.increased with the increase of OSA dosage.Fourier transform infrared spectroscopy analysis indicated that starch ester existed the absorption peaks of ester carbonyl group and carboxylic acid at 1732 cm-1 and 1558 cm-1.Scanning electron microscopy showed that the morphology of OSA starch ester of Cyperus Esculentus L.was no obvious change.Some slight corrosion and cracks on the surface of starch ester of Cyperus Esculentus L.could be found.X-ray diffraction analysis confirmed that with the deepening of the esterification reaction,the partial crystal structure of starch esters was destroyed,and the relative crystallinity of starch decreased.