Effects of Processing on Phytonutrient and Nutritional Composition of Finger Millet (Eleusine coracana): The Neglected Crop of Africa

Abstract

Millets are termed as nutricereals since they are nutritionally superior to major cereals with respect to protein, energy, vitamins and minerals. The aim of  this research was to investigate the effects of processing techniques on the proximate composition and reduction of phytonutrients in finger millet  grains. Germination (72hrs) and natural fermentation (24hrs) process of finger millet seeds improved crude protein. A significant (p<0.05) variation was  noticed within 72hrs of germination in the total amount of calcium, iron and phosphorous due to the transfer of nutrients from the seed material to the  growing embryo. The flour was extruded at a temperature of 110 ºC and 130ºC, a screw speed of 200 and 250 rpm, and 17 and 21 feed moisture content.  The highest expansion ratio and lowest bulk density was obtained at temperature of 130 ºC, screw speed of 250 rpm and 17% moisture content. A  significance difference was observed during extrusion processing on elimination of phytate as compared to germination and fermentation. Fermentation  (48 hrs) and extrusion (130 ºC) were found to be the best process methods for the reduction of the phytate and tannins, respectively. The  improved physical properties of extrudates and level of reduction of phytonutreints indicate the possibility of diversifying utilization of finger millet in the  form different indigenous community based added value products and novel commercial value added products at manufacturing industry level.