The Extrusion Cooking of Potato Starch Material

Abstract

Abstract The effect of extrusion cooking on the pasting properties of potato starch materials is examined using a Couette rheometer. The dispersion viscosity of aqueous dispersions of potato starch, pregelatinized potato starch and commercial potato granules has been investigated. The effect of extrusion moisture and progress down the extruder on this property has been studied. The dispersion viscosity response is related to the gelatinization and disruption of starch granules. Extrusion at high moisture levels leads to high viscosity dispersions tending to that of gelatinized starch whereas low moisture levels result in lower viscosity dispersions.