A Comparative Study on Isolation and Characterization of Millets Varieties

Vaishnavi V, Ramkumar G, Rabi A Sakthibala M, Saminathan C

The present study investigates the isolation and physicochemical characterization of starch from three varieties of millet: foxtail millet, little millet, and Kodo millet. Starch was isolated using an alkaline extraction method, and the yield was determined for each millet variety. Kodo millet demonstrated the highest starch yield (74.50%), followed by foxtail millet (68.54%) and little millet (45.35%). The isolated starch was subjected to iodine testing, confirming its identity with a characteristic blue-black coloration. Physicochemical properties of the starches were evaluated, including swelling power, angle of repose, bulk density, tapped density, Hausner’s ratio, and Carr’s index. Foxtail millet exhibited the highest swelling power (16.42%), while little millet had the highest angle of repose (35.30°), indicating poorer flow ability. Kodo millet showed superior bulk and tapped densities (0.81 g/ml and 0.96 g/ml, respectively), along with the lowest Hausner’s ratio (1.18) and Carr’s index (15.62%), suggesting better flowability and packing efficiency. These characteristics indicate that Kodo millet starch is more suitable for applications requiring higher packing efficiency and good flowability.Viscosity measurements were conducted using a Brookfield viscometer, where Kodo millet starch exhibited the highest viscosity among the three varieties. At a 4% starch concentration, Kodo millet starch displayed a viscosity of 21.31 centipoise, surpassing foxtail (18.76 centipoise) and little millet (13.28 centipoise).These findings highlight the distinct physicochemical properties of millet starches and provide insights into their potential applications in food processing, packaging, and industrial uses. Kodo millet, with its superior packing and flow properties, shows promise for commercial starch production, while foxtail and little millet can be considered for specialized applications depending on their functional characteristics.

Keyword: Millets, Starch, Nutraceuticals and Isolation of Starch