非晶化玉米淀粉的理化性质

Physicochemical properties of non-crystalline maize starch

摘要:

为研究球磨法非晶化玉米淀粉的理化性质,采用扫描电镜、X-射线衍射仪、差示扫描量热仪、快速黏度分析仪和全自动气体吸附仪等分析手段研究非晶化淀粉的颗粒形貌和理化性质.结果表明:非晶化玉米淀粉颗粒破裂,偏光十字消失,相对结晶度由原玉米淀粉的23.4%下降到1.91%,淀粉从多晶态转至无定形态;糊化温度、热焓值均降低,糊化吸收峰消失;比表面积增大,粒度分布变宽、粒径增大,颗粒平均孔径增大;溶解度、膨胀度和持水能力均提高;而淀粉糊浊度下降,特征黏度值均小于原玉米淀粉,非晶化玉米淀粉热糊稳定性和冷糊力学稳定性均优于原淀粉.

Abstract:

The physiochemical properties of non-crystalline maize starch made by ball milling were studied in this paper.The granular morphology and physicochemical properties of it were further characterized using scanning electron microscopy,X-ray diffractometry,differential scanning calorimetry,rapid visco analyser and specific surface area analyzer.The results show that non-crystalline maize starch granules lose smoothness on surface and become rough,the Maltese crosses of non-crystalline maize starch disappear and its relative crystallinity is decreased from 23.4% to 1.91% ,the gelatinization temperature and enthalpy of non-crystalline maize starch decrease and the phase transition peaks disappear gradually during gelatinization.The crystal structure of non-crystalline maize starch is changed from polycrystalline to amorphous.Compared with native starch,except turbidity,all other property factors of non-crystalline maize starch,such as specific surface area,specific pore volume,particle size,size distribution,the solubility,swelling power and water binding capacity are significantly increased.For non-crystalline maize starch,its turbidity and viscosity are lowered,while its hot paste stability and mechanical stability are better than those of native maize starch.