Influence of depigmentation of pearl millet (Pennisetum gluacum L.) on sensory attributes, nutrient composition and in vitro digestibility of biscuits

Presence of high concentration of pigments in the pericarp and endosperm regions of pearl millet imparts undesirable gray color to its products. This study attempts to improve the acceptability of pearl millet products through processing technique and to study its effect on nutritional composition of pearl millet product. Pearl millet grains were depigmented by soaking in 0.2 N HCl for 18 h followed by washing, blanching at 98°C for 30 s and sun drying. Three different types of biscuits were prepared from refined flour (Reference), native or unprocessed pearl millet (T-I) and depigmented pearl millet (T-II). Results indicated that depigmentation improved the sensory attributes especially the color of pearl millet biscuits (T-II). The protein, fat, ash and total dietary fiber of pearl millet based biscuits (T-I as well as T-II) were significantly (P?0.05) higher than the reference biscuits. Depigmentation significantly improved the in vitro starch digestibility, in vitro protein digestibility and the soluble dietary fiber content of pearl millet biscuits (T-II) by 14.50, 6.56 and 6.18%, respectively. On the other hand, a significant decrease of 6.73, 2.43 and 17.03 g/100 g in protein, starch and insoluble dietary fiber was detected in pearl millet biscuits (T-II) due to depigmentation.