【摘要】 玉米淀粉和马铃薯淀粉分别在 35℃条件下用浓度为 2 .4 mol/ L的 HCl处理不同时间 ,采用 X射线衍射分析、差热分析和扫描电镜等测试方法对酸解后的淀粉颗粒进行结构和性能分析。结果表明 ,淀粉的酸解过程可分为两个阶段 :首先淀粉无定形区进行水解 ,颗粒结晶度、结晶热稳定性和酶解速率增加 ;随着酸解时间的延长 ,结晶结构受到破坏 ,热稳定性降低 ,达到酶解平衡的时间减少。酸解 4 d时 ,玉米淀粉和马铃薯淀粉颗粒的结晶均最完整 ,结晶转变温度最高 ,分别为 87.0℃和 93.5℃。更多还原

【Abstract】 Maize and Potato starch were treated with 2 4mol/L hydrochloric acid at 35℃ for different times.The remaining starch granules after acid hydrolysis were analyzed the crystallinity by X-ray diffraction,the microstructure by scanning electron microscopy(SEM)and the thermal-stability by DTA.The results indicated that the acid hydrolysis on starch occurred in two steps:firstly a quick degradation of the amorphous areas occurred with the increasing of crystallinity,thermal-stability and the speed of enzyme-hydrolysis;and then thermal-stability and reach equilibrium time of enzyme-hydrolysis decreased with the increasing of hydrolysis time and crystalline disintegration.In the fourth day,the crystallinity was perfect and thermal-stability was the best.The crystalline transition temperature was 87 0℃ and 93 5℃ for maize starch and potato starch,respectively.更多还原