Amino Acid Composition and Nutritional Indices of Flour and Biscuit from Wheat and Bambara Groundnut Blends

Abstract

The aim of this study was to determine the amino acid composition and nutritional indices of bambara groundnut, an underutilised legume for use both as flour and protein isolate in biscuit production. Sixteen (16) response surface methodology (RSM) runs were evaluated from combination of wheat flour (WF), bambara groundnut flour (BF) and bambara protein isolate (BPI). Based on the crude protein and functional properties these ratios were selected WF: BF (85.0:15.0%, 76.2:23.8% and 52.5:47.5%) and labeled as WBF₁, WBF₂, WBF₃, respectively with WF: BPI (85.0:15.0%, 76.2:23.8% and 52.5:47.5%) as WBPI₁, WBPI₂ and WBPI₃ for blends of wheat flour and bambara protein isolate respectively. The amino acid of the flour and biscuit from bambara groundnut was investigated. Data were analysed using one-way analysis of variance (ANOVA) and significance at P<0.05. The limiting and most abundant amino acids were methionine in wheat-bambara composite flour (32.73-90.24) and biscuit (58.64-131.36) and arginine in wheat-bambara composite flour (149.50-429.00) and biscuit (98.37-307.50). The essential amino acid index (EAAI) of wheat-bambara composite flour ranged between (57.16- 66.35) and (37.06 – 76.49) for biscuit. The Protein Efficiency Ratio (PER) of wheat-bambara composite flour and biscuit were (2.40-2.70) and (1.70 – 3.05) respectively. The Biological Value (BV) ranged between (50.60- 60.63) for wheat-bambara composite flour and (47.17–66.99) for biscuit. Hence, the essential amino acids in the composite flour and biscuit will adequately support growth and development in infants, children and adults.