摘要
利用ＳｅｐｈａｄｅｘＧ－２００凝胶过滤层折，碘吸附值，碘络合物吸收光谱，Ｘ－射线衍射光谱等方法对挤压淀粉进行了研究。结果表明，玉米淀粉在挤压过程中，其直链级分未发生显著变化，支链级分的降解位置位于其分子内部，挤压施加于淀粉聚合物的剪应力是挤压淀粉中直链淀粉脂肪络合物的Ｖ型结构向Ｅ型结构转换的根本原因。依据淀粉的聚集态结构，从理论上阐述了淀粉在挤压过程中降解的力化学过程，并提出淀粉降解可能为自由基过程的机理。
The extruded cron starch samples were analysed by Sephadex G-200 gel filtration chromatography,Iodine affinity value,Iodine absorption spectrum,X- ray diffraction. The results showed that there were almost no changs of the amylose during extrusion,the branch point of the amylopectin ruptured by extrusion was within the gross structure of the amylopectin,the transformation from the V amylose structure to the Eamylose stucture depended on the shearing stress imposed by the extrusion. From the view of the aggreated structure of the amylose and amylopectin in corn starch granulas,the physicochmical process and degradation mechanism of corn starches during extrusion were elaborated.The free radical activated intermediate might exist during extrusion.
关键词
玉米淀粉
挤压蒸煮
力化学降解
orn starches
Extrusion cooking
Mechanochemical degration
