Abstract
<title>Abstract</title> <p>Polished maize-based complementary foods are widely consumed by children aged 6–24 months but are often limited in protein and micronutrient content. This study evaluated the effect of partially substituting polished maize flour with oyster mushroom flour (0%, 10%, 20%, 30%, and 40% w/w) on the nutritional composition and sensory acceptability of polished maize-mushroom composite flours. Proximate composition, mineral content, estimated nutrient contribution to recommended daily allowances (RDA), and caregiver sensory preferences were determined using standard analytical methods. Increasing oyster mushroom flour inclusion significantly improved the nutrient profile of the composites. Crude protein increased by 1.07–11.20%, while ash and crude fiber increased by up to 2.48% and 3.04%, respectively, with the highest values observed at 40% substitution. Similarly, mineral content increased significantly with mushroom flour inclusion. Iron and zinc increased by 2.7-8.88-fold and 1.9-6.0-fold, respectively, while calcium and magnesium showed percentage increases ranging from 3.5% to 55.33%, with calcium recording the highest increment. Although carbohydrate and energy contents decreased with increasing mushroom levels, all blends contributed more than 53% and 100% of the estimated energy gap for non-breastfed and breastfed children aged 6–11 months, respectively. The 40% blend contributed up to 88.9% and 78.2% of the iron RDA for children aged 6–11 and 12–24 months, respectively. Sensory scores declined significantly with increasing mushroom inclusion; however, the 10% blend was not significantly different from the control in overall acceptability. Incorporation of oyster mushroom flour, particularly at 10–20% substitution, enhances the nutrient density of polished maize-based complementary foods while maintaining acceptable sensory quality.</p>