马铃薯淀粉颗粒的粒度与酶解特性相关性研究

Relationship of potato starch granule and its enzymatic hydrolysis properties

淀粉颗粒分级目前主要通过机械粉碎的方法实现,由于粉碎导致淀粉颗粒破损,在酶解过程中很难科学阐述淀粉的完整颗粒结构与酶解特性关系。基于此,通过自主构建颗粒沉降系统,在不破坏淀粉颗粒结构的前提下分级得到不同粒度的马铃薯淀粉颗粒,其平均等效粒径分别为17.39,25.81,38.77,56.53μm;采用酶解动力学等方法,研究发现淀粉颗粒越小,其比表面积越大,酶解效率越高;淀粉颗粒的消化速率系数与其尺寸大小呈负相关。综上可知,小颗粒马铃薯淀粉可作为多孔淀粉的制备原料,大颗粒马铃薯淀粉可作为抗性淀粉的制备原料。

Mechanical pulverization was generally used to fractionate starch granules, but this method produced broken starch granules, thus resulting in the difficulties in finding the relationship between particle size of starch granule and hydrolysis efficiency by enzymes. Therefore, a sedimentation method based on stokes law was devel- oped to produce unbroken starch granules with different particle sizes. The results showed that four sizes of starch granules were obtained and their average equivalent particle diameters were 17.39, 25.81, 38.77, and 56.53μm, respectively. Furthermore, smaller starch granules possessed large specific surface and exhibited higher hydrolysis rate. A negative correlation was observed between granule size and digestion rate （K）. These findings suggest that smaller starch granules could be used as materials for porous starch and larger starch granules could be applied to prepare resistant starch.