Proximate composition and functional properties of different grain flour composites for industrial applications

Abstract

Purpose: The study focused on evaluating proximate compositions and functional properties of different flour blends.
 Methodology: Three representative flour samples were produced from each mixture of maize-millet, soybean-wheat, and rice-wheat in the ratios of 70:30, 50:50, and 30:70 percent for all combinations. The proximate composition and functional properties of flour blends were determined using the methods of AOAC.
 Findings: There was significant difference in the proximate compositions of the flours (p =0.05). The moisture content of the blends was highest at 5.41% for maize-millet blend ratio of 70:30% and lowest at 1.8% for soybean-wheat blend ratio of 30:70%. The crude protein content of the grain flour samples ranged from 16.32% to 44.10%. Soybean-wheat flour blend had the highest fat content of 7.34% for 70:30% and maize-millet blend had the least fat content of 1.30 for 50:50%. Maize-millet flour blend had the highest ash content of 4.02% for 30:70% and lowest for rice-wheat with 0.35% for 50:50%. The percent carbohydrate content of the flours ranged from 42.60% to 65.01%. The percent crude fibre content of the flours ranged from 2.13% to 10.01%. Soya bean-wheat flour blend had the highest average crude fibre content. There was significant difference in the functional properties of the flour blends (p =0.05). The oil absorption capacity (OAC) of the flours ranged from 1.00 to 2.25 ml/g. The rice-wheat flour blend had the highest water absorption capacity (WAC) of 2.60 ml/g for 30:70% blend ratio, while the lowest WAC was 0.50 ml/g for soybean-wheat blend. The foaming capacity (FC) of the flour blends ranged from 10.83 to 15.40%, while the emulsion capacity ranged from 35.05% to 50.95%. The swelling index ranged from 1.13% to 1.98%. The high emulsion capacity of soybean-wheat flour blend suggested that it was more digestible and therefore could be suitable for use as ingredient in infant food formulations.
 Unique contribution to theory, practice and policy: The high swelling index indicates that rice-wheat flour blend could be more suitable in food systems where swelling is required. The high emulsion capacity of soybean-wheat flour blend suggested that it was more digestible and therefore could be suitable for use as ingredient in infant food formulations.