Preparation and functional properties of decorticated finger millet (Eleusine coracana) S. Shobana, N.G. Malleshi * Department of Grain Science and Technology, Central Food Technological Research Institute, Mysore 570 020, India Received 6 October 2004; received in revised form 31 August 2005; accepted 17 January 2006 Available online 18 April 2006 Abstract 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 car- borundum 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. Ó 2006 Elsevier Ltd. All rights reserved. Keywords: Cooking characteristics; Decortication; Endosperm texture; Finger millet; Hydrothermal treatment 1. Introduction Finger millet or Ragi (Eleusine coracana) is an impor- tant staple food for the traditional consumers and the peo- ple belonging to the lower socio-economic strata in the Indian subcontinent and also in some of the African coun- tries. It is a small seeded (1.2–1.8 mm diameter) minor cer- eal having, light brown to brick red coloured seed coat with minutely undulated surface. Its pericarp is membranous, thin layered and loosely attached tissue covering the entire seed and generally detaches during harvesting or by simple abrasion. On the other hand, the seed coat or the bran con- sisting of highly pigmented testa fused with the aleurone layer, is rigidly attached to the endosperm (McDonough, Rooney, & Earp, 1986). The endosperm texture of the millet kernels consists of largely floury portion and crumbles to fine grits when the seed coat is partially or fully peeled off. In view of these textural peculiarities, efforts to decorticate the millet by known cereal milling methodologies including abrasion or friction mills or following such other dehulling methods have not been successful till date. Because of this, the millet is invariably pulverized to flour and the whole meal is used to prepare the conventional foods, namely, unleavened pancakes (roti), stiff porridge or dumpling (mudde) and thin porridge (ambali)(Malleshi & Hadimani, 1991). The seed coat normally imparts dark colour, chewy texture and characteristic musty odour to the food products and these factors largely hinder their acceptability by the non-traditional millet consumers. Some of health benefits associated with regular intake of millet foods, such as the hypocholesterolemic, hypoglycemic and antiulcerative 0260-8774/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.jfoodeng.2006.01.076 * Corresponding author. Tel.: +91 821 2510843; fax: +91 821 2517233. E-mail address: malleshi@yahoo.com (N.G. Malleshi). www.elsevier.com/locate/jfoodeng Journal of Food Engineering 79 (2007) 529–538