Finger millet being a source of high class nutrition was used to develop Ready-to-eat (RTE) extruded product through extrusion cooking. The proportion of finger millet grain was kept as 50, 40 and 30 percent in the flour formulation in order to study the influence of processing parameters. Finger millet flour level was decreased from 50 to 30 per cent. Maize flour level kept constant as 30 per cent. Sweet potato and greengram flour level was varied with finger millet level. The twin screw parameters temperature 100, 125 and 1500C as well as screw speed 150 and 350 rpm on the extrudate.
The effect of extrusion temperature on extrudates for composite flour of finger millet, greengram, sweet potato and maize was investigated for functional properties namely expansion ratio, bulk density, Water absorption index (WAI), Water solubility index (WSI), colour and hardness. Protein content of finger millet extrudates decreases with increase of extrusion temperature. Flour formulation of 30% finger millet, 20% sweet potato, 20% greengram and 30% maize at barrel temperature 150oC and screw speed of 350 rpm provides best finger millet based extrudate having maximum expansion ratio, lowest bulk density, lowest hardness and best attractive colour. Finger millet extrudates of 30 percent finger millet with 30 percent maize, 20 percent sweet potato and 20 percent greengram showed better functional properties as compared to all other treatments