PROXIMATE COMPOSITION AND PHYSICOCHEMICAL PROPERTIES OF JACK BEAN, BAMBARA GROUNDNUT, MILLET FLOUR, STARCH AND PROTEIN CONCENTRATE

Abstract

Jack beans (Canavalia ensiformsi), bambara groundnut (Vigna substerranean) and Millet (Pennisetum glaucum) grain legumes which are good source of protein and carbohydrate. little or no study has been conducted on the proximate composition and physicochemical properties of the starch and fatty acid of the oil produced from jack bean, bambara groundnut and millet seeds flour. Thus, the present work is to carry out the proximate, mineral, fatty acid and amino acid composition and some physicochemical properties of the flour, starch and protein concentrate. The dried seeds were processed into flour, starch and protein concentrate and evaluated for its proximate, mineral, amino acid and fatty acid composition using standard analytical techniques. Some physicochemical properties and pasting properties of the samples flour, extracted starch and protein concentrate were also determined. The crude protein, moisture, ash, crude fibre, crude fat and carbohydrate by difference ranged from 20.79 to 31.72%, 7.56 to 9.29%, 2.28 to 3.45%, 2.73 to 3.50%, 6.60 to 8.27% and 44.94 to 61.12% respectively for the samples flour, 1.32 to 1.75%, 7.12 to 8.97%, 0.96 to 0.97%, 0.96 to 0.99%, 1.89 to 1.93% and 85.43 to 89.18% respectively for the extracted starch and 61.25 to 77.66%, 5.94 to 9.00%, 1.96 to 4.96%, 1.91 to 1.96%, 0.49 to 0.52%, 9.03 to 25.34% respectively for protein concentrate. All the studied samples were found to have considerable amount of essential minerals such as Mg, Ca, Na and K but low quantities of Fe, Cu, Zn, Mn, Ni, Cr while Pd and Cd were not detected. The amino acid analysis revealed that the samples flour contained nutritionally useful quantities (g/100g crude protein) of essential amino acid (Leu, Lys, Phen and Thre) and the protein concentrate are rich in essential amino acids. The fatty acid analysis showed that millet oil (MO) had the highest percentage value (65.31%) oleic acid but low percentage value (15.86%) in jack bean oil (JBO) while it was not detected in bambara groundnut oil (BGO). High percentage of linoleic acid was found in bambara groundnut oil and not detected in jack bean and millet oil. The total unsaturated fatty acid followed the order: (65.83%) MO > (44.39%) BGO> (15.86%) JBO while the total saturated fatty acid followed the order: (48.96%) BGO > (33.83%) > (13.05%) JBO. The water absorption capacity, oil absorption capacity, least gelation capacity, foaming capacity, foaming stability, bulk density and pH observed ranged from (0.27 to 2.97 g/ml), (1.40 to 2.80 g/ml), (6.00 to 10.00 %), (4.40 to 6 37 g/ml), (8.73 to 14.33 g/ml), (1.70 to 3.93 g/ml), (0.50 to 0.63 g/ml) and (4.77 to 5.07 g/ml) for flour; (1.20 to 1.80 g/ml),(1.07 to 1.77 g/ml), (6.00 to 10.00 %), (2.80 to 6.77 g/ml), (3.07 to 6.07 g/ml), (1.07 to 3.07 g/ml), (0.50 to 0.63 g/ml) and (3.23 to 6.07 g/ml) for extracted starch and (1.00 to 2.03 g/ml), (1.87 to 2.77 g/ml), (14 to 16 %), (1.83 to 2.26 g/ml), (5.07 to 6.07 g/ml), (0.50 to 1.80 g/ml),(0.62 to 0.77 g/ml) and (4.47 to 5.44 g/ml) for protein concentrate. The result showed pasting temperature (Ptemp), pasting time (Ptime), pasting viscosity (PV), trough viscosity (TV), final viscosity (FV), breakdown viscosity (BD) and setback viscosity (SB) showed values ranged from (4.23 to 5.27 mins), (77.83 and 84.83OC), (313.50 to 1985.00cp), (74.50 to 1108.00cp), (98.50 to 2677.00cp), (221.00 to 239.00cp) and (24.00 to 1569.50cp) for the flour and (4.23 to 5.97 mins), (82.75 to 88.88OC), (1539.50 to 5674.00cp), (902.00 to 3826.50cp), (637.50 to 1847.50cp), (1340.00 to 5936.50cp) and (438 .00 to 2740.00cp) for the extracted starch. The pasting viscosities of the samples flour were lower than those of samples extracted starch. Result revealed that the samples had good least gelation capacity thus will be useful in preparing sauce. Also, the high setback viscosity observed in the starch revealed it is very good and stable, thus will be very useful in bread making. Moreover, the samples will be useful raw materials in industrial applications.