Preparation and functional properties of decorticated finger millet (Eleusine coracana)

摘要

The food uses of finger millet are confined to flour based products because, it has not been possible to decorticate the millet similar to other cereals. This is mainly due to the highly floury endosperm. But, it was observed that, the hydrothermal treatment to the millet hardens the endosperm texture and enables its decortication. Accordingly, the optimal conditions for the hydrothermal treatment and also for decortication of the millet were determined. Equilibrating the millet to 33 ± 2% moisture content and steaming the same for about 20 min at atmospheric pressure followed by drying to 12 ± 2% moisture content enhanced the hardness of the millet kernel from 1.1 ± 0.2 to 7.1 ± 0.5 kg/cm~2 and enabled its decortication. Among the various cereal pearlers and decorticators, horizontal carborundum disc mill was most suitable and incipient moist conditioning the millet improved the decortication efficiency. The decorticated millet contained 6.3 ± 0.6 g protein, 0.9 ± 0.2% fat, 14.7 ± 1.8% dietary fibre, 0.180 ± 0.015% calcium and 0.109 ± 0.01% phosphorus. The polyphenols and phytate phosphorus content of the decorticated millets were lower by 74.7% and 39.8%, respectively, as compared to the native millet. The decorticated millet could be cooked as discrete grains similar to rice to soft edible texture within 5 min which was not possible hitherto. The pasting and the dough properties and also some of the functional characteristics of the product indicated its versatility for diversified food uses.