Millets would be widely used if processing were improved and if sufficient good quality flour were made available to meet the demand. Quality flour production suitable to various products could be possible when there is complete evaluation of millet flours using different processing techniques hence the present study focused on evaluating the impact of extrusion cooking on the functional, nutritional, thermal characteristics and shelf life of browntop millet flour. Whole and dehulled browntop millet grits were extruded at 140, 150°C respectively and made into flour for further analysis following standard procedures. The swelling power of analysed samples ranged from 203.0±0.6 to 621.3±0.9 with DBF (Dehulled Browntop millet Flour) being the least and DEBF the highest. Significant improvement upon extrusion was observed for WAC%, WHC%, OAC% and ORC%. Moisture content varied from 7.43±0.27 to 8.99±0.06. Significant reduction in the moisture content upon extrusion was noted but no great enhancement in the protein content. The ash content of the analysed flours ranged from 2.16±0.17% in EWBF to 5.43±0.27% in WBF. Decrease in the ash content was found in extruded samples. Fat content in the analysed samples was found to be in the range of 3.78±0.12% in EWBF to 6.27±0.15% in DBF, reduction in the fat content was observed due to extrusion. Carbohydrate content and calorific values were greater in the extruded browntop millet flour than native flours. Increase in the gelatinization temperatures (Onset To (ºC), Peak Tp (ºC), Conclusion Tc (ºC)) and pasting temperature, pasting viscosity was observed in extruded browntop millet flours. The storage (G’) and loss modulus (G”) were reduced due to extrusion in whole and dehulled samples. Shelf life study indicated that moisture, water activity, TMC and TBC of the analysed samples were within the acceptable range. The results highlight the potential use of extrusion cooking to develop quality browntop millet flour with optimal nutritional composition, functional and thermal properties with good keeping quality.

Browntop millet, extrusion, functional properties, nutritional properties, thermal properties

From the current study it can be concluded that utilization of either extruded whole or dehulled browntop flours are beneficial, however, a relative benefit is observed in extruded flours in terms of higher nutrients, better functional and thermal properties with good keeping quality.

K. Santhi Sirisha, S. Suchiritha Devi, T. Supraja, R. Neela Rani and D. Kalpana (2022). Functional, Nutritional and Thermal properties of Extruded Browntop Millet Flours. Biological Forum – An International Journal, 14(4a): 360-366.