Nutrient Composition And Organoleptic Attributes Of Gruel Based On Fermented Cereal, Legume, Tuber And Root Flour

Abstract

The nutrient composition and organoleptic attributes of gruel based on blends of 24-hour fermented wateryam (WY), cocoyam (CY), plantain (PT), african yam- bean (AYB), cowpea (CP), pigeon pea (PP) and corn (C) flour were examined. A batch of each food-grain was picked clean, sun-dried, hammermilled into flour(40mm mesh screen) and put in polyethylene bag. Root, tuber and plantain were first peeled, sliced, sun-dried and milled into flour(40mm mesh screen) and also put in polyethylene bag. The flour batches were separately put in a container and were subjected to natural fermentation in de-ionized water in the ratio of 1:3 (w/v) at 28 ± 20C for 24 hours as pilot studies indicated that fermenting beyond this period produced off-odour in tuber, root and plantain. The fermented samples were dried at 55 ± 20C in a drought air oven (Gallenkamp, BS Model 250 size 2 UK), hammer milled into fine flour (70mm mesh screen) and stored in a refrigerator( 5 ± 20C) until used for the chemical analysis and production of gruels. The nutrients of the flour were determined by standard methods. The flour was blended in a ratio of 70: 30 to prepare various gruels on protein basis. Legume flour formed 70% of the blends. The C, WY, CY, PT flour formed the other 25, 5, 3 and 2% of the blends, respectively. Corn flour traditionally used to make gruels served as the control. The nutrient levels and organoleptic attributes of the gruels were evaluated using standard methods. The data was statistically analyzed using means, standard error of the means and Duncan’s multiple range test to separate and compare means. Fermentation caused increases in various nutrients. African yam-bean, cowpea, pigeon pea, water-yam and cocoyam flour had increases in protein due to fermentation except for corn and plantain. It increased fat only in AYB, CY and PT. Ash and fibre
were decreased in all the flour samples due to fermentation. The results showed that the gruel samples made from fermented blends contained various proportions of nutrients that ranged from 18.24 - 21.34% protein, 1.80 - 2.61% fat, 1.66 - 2.86% ash and 73.98 - 77.14% carbohydrate. The mineral levels were moderate except for phosphorus and calcium that ranged from 360 - 626mg and 318.20 - 376.60mg, respectively. The CP24C24CY24PT24 blend had the highest nutrients except for fat, carbohydrate and copper as against other test blends. The blend that had the highest nutrients had the highest organoleptic attributes. As judged by the results, the blend that had high food potentials could be used as
complementary foods.

Keywords: Gruel, nutrient composition , fermented blends, organoleptic test, cocoyam, Xanthosoma sagittifolium.