Bridging Crop Improvement for Feeding Children 6-23 months: Cowpea and Soybean Varieties in Zambia-A laboratory analysis

Abstract

Background Improving complementary feeding for children aged 6–23 months is a public health priority. Cowpea and soybean can address protein and micronutrient gaps, yet genotype-specific nutrient profiles remain poorly characterized in Zambia. Objective To assess genotype-specific nutrient composition and mineral interactions relevant to feeding of children aged 6-23 months in Zambia. Design A laboratory-based cross-sectional study assessed nutrient composition using Association of Official Analytical Chemists (AOAC) and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) methods. Participants /Setting: Ten cowpea genotypes (four released varieties and six breeding lines) and seven soybean genotypes (five released varieties and two breeding lines) from the University of Zambia were analyzed at the Zambia Bureau of Standards (ZABS). Methods Mineral variability and associations were assessed using medians with ranges, Spearman's correlations, principal component analysis (PCA) and cluster analysis. Results Soybean genotypes were higher in energy (473 kcal/100 g), protein (43%), fat (21%), Ca, P, Cu, Zn, and Se; cowpea genotypes were higher in carbohydrates (47%), fiber (7%), K, Mg, and Fe. Cowpea genotypes showed significant positive correlations among Cu–Zn, Ca–K/Mg/Na/P and K–Mg/Na/P (r=0.65–0.94; p<0.05), while soybean genotypes showed a similar pattern between Mg–P (r=0.96; p<0.05); negative associations were weak. Cowpea genotypes PCA explained 76.52% of variation (PC1=60.30%; PC2=16.22%), while soybean genotypes PC1 explained 41.47%. Cluster analysis corroborated PCA-based genotype differentiation. Conclusions Nutrition-sensitive selection of cowpea and soybean genotypes may have potential to support dietary adequacy among children and other population groups at risk of poor nutritional status