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

In order to inquire into the rheological 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 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 behavior index n changes little.As the increasing of mass ratio,the coefficient K increases,however,the index n decreases.