Functional Properties of Kidney Bean-fortified Wheat–cassava Composite Flour and Chemical Properties of Cookies Produced in Imo State, Nigeria

Abstract

This study evaluated the functional properties of kidney bean-fortified wheat–cassava composite flour and the chemical properties of cookies produced in Owerri, Imo State, Nigeria. Four flour formulations were prepared: WCKA (100% wheat flour), WCKB (80% wheat, 15% cassava, and 5% kidney bean), WCKC (80% wheat, 10% cassava, and 10% kidney bean), and WCKD (80% wheat, 5% cassava, and 15% kidney bean). The functional properties of the composite flours, including bulk density, water absorption capacity, oil absorption capacity, swelling capacity, foaming capacity, and least gelation concentration, were determined. The cookies were analysed for micronutrients (calcium, iron, magnesium, phosphorus, potassium, zinc, thiamine, riboflavin, niacin, and folate) and anti-nutritional factors (phytate, oxalate, tannin, and saponin) using standard analytical methods. The data were analysed using analysis of variance (ANOVA), and the means were separated using Duncan's multiple range test at p < 0.05. The results showed that increasing the proportion of kidney bean flour significantly (p < 0.05) improved the micronutrient composition of the cookies. Calcium increased from 18.40 to 30.42 mg/100 g, iron from 1.52 to 3.31 mg/100 g, and folate from 22.10 to 41.52 µg/100 g. Anti-nutritional factors also increased slightly but remained within acceptable limits. The functional properties of the composite flour improved with fortification: water absorption capacity increased from 1.42 to 1.88 g/g, oil absorption capacity increased from 1.21 to 1.56 g/g, and bulk density decreased from 0.71 to 0.62 g/mL. The study concluded that kidney bean fortification enhanced the nutritional quality of wheat–cassava composite cookies and improved the functional properties of the composite flour. The incorporation of up to 15% kidney bean flour is recommended for producing nutrient-enriched cookies from locally available raw materials.