淀粉粒度对马铃薯淀粉糊流变特性的影响

Research on the Rheological Characteristics of Potato Starch Affected by Particle Size

为了探讨淀粉粒度效应对淀粉糊流变特性的影响,以马铃薯淀粉为原料,制备了不同粒度的微细化淀粉.利用X射线衍射仪和扫描电镜测试不同粒度淀粉的结晶情况,分析了不同粒度淀粉的相态结构,并将其制成不同质量分数的淀粉糊;利用ND J-79旋转式粘度计对马铃薯淀粉糊进行了粘度测定,并对其流变特性进行了分析.结果表明:机械研磨作用能够明显地破坏淀粉分子的结晶结构,导致其结晶度降低,而无序化程度增加;马铃薯淀粉糊仍然是假塑性非牛顿流体,其流变特性服从幂律指数模型.随着淀粉颗粒粒径的减小,其稠度系数减小,流变指数基本上没有变化,随着淀粉粒度的增大其稠度系数增大,流变指数减小.

In order to inquire into the theological characteristics of potato starch by particle size, micronized potato starch particles and their pastets have been prepared. The morphology studies on the potato starch particles have been conducted using XRD and SEM. Viscosity of potato starch saccharification liquor was measured to obtain the rhological properties by NDJ-79 type viscosity meter. The experimental results have shown that the crystal structure of starch has been destroyed by mechanical grinding The experimental results have shown that the crystal structuret-which leads to a low crystallizability and disordering ; and the liquor has shown a behavior of pseudoplastic non-Newtonian fluid and its rheological characteristics meet with power-law indexmodel. The consistency coefficient K decreases with the increase of particle size, while the flow be-havior index n changes little. As the increasing of mass ratio, the coefficient K increases, however, the index n decreases.