Effect of ethanol addition on physical properties of extruded starch

Abstract

AbstractThe aim of this study was to determine selected properties of extrudates produced from potato starch with the addition of ethyl alcohol. Ethyl alcohol at 5, 10, 15, and 20% concentration was added to potato starch with moisture content of 18 and 23%; the starch was then extruded in single‐screw extruder. The extrusion process was carried out in three temperature variants. The resultant extrudates were determined for color, expansion ratio, and mechanical properties. Properties of the extrudates were found to depend on parameters of the extrusion process, moisture content of the extruded sample and ethanol content. Morphological characteristics of the extrudates produced were affected by temperature of the extrusion process, i.e., increasing extrusion temperature resulted in a higher expansion ratio, a lower density, and higher saturation of white color. The extrudates produced from starch with the addition of ethanol were whiter, than those prepared without ethanol. The samples produced with ethanol addition were characterized by a higher number of air spaces and thinner walls, when compared to the those prepared from starch moistened only with water. All mechanical properties were lower in the samples prepared with the addition of ethanol, as compared to the extrudates without its addition.