Effects of Extrusion Conditions on Physicochemical Properties of Finger Millet (Gramineae Setaria)

In this study, the effects of different extrusion parameters (extrusion temperature: 100, 130, and 160 °C; moisture content: 22%, 26%, and 30%; screw speed: 180 rpm, 270 rpm, and 360 rpm) on physicochemical properties of finger millet were reviewed. High extrusion temperature produced extrudates with high radial expansion index (REI) and starch digestibility and low bulk density (BD). High moisture content and low screw speed increased BD and total starch content (TSC) while decreasing REI and water solubility index (WSI). WSI and starch digestibility first increased and then decreased with increase in extrusion temperature and moisture content, which reached a maximum at 130 °C nd 26%, respectively. However, water absorption index (WAI) was affected by the interactions among various conditions. The extrudates were darker and yellower than native millet. Based on these extrusion conditions, various millet and millet-based products can be produced.