Quality Evaluation of Ogi Powder Made from White Maize and Defatted Watermelon Seeds

Ogi, a traditional fermented cereal product, is commonly consumed in many African countries but is limited by low protein and micronutrient content. Enhancement of ogi’s nutritional value was achieved by fortifying it with increasing levels of defatted watermelon seed powder. This produced five samples: a control (XYC2) containing 50% ogi powder and 0% watermelon seed powder, and four fortified variants; XYA (45% ogi, 5% seed powder), XYB (40% ogi, 10% seed powder), XYC (35% ogi, 15% seed powder), and XYD (30% ogi, 20% seed powder). Proximate analysis revealed significant improvements in nutrient composition with fortification. Protein content increased from 12.31% in the sample XYC2 to 22.09% in XYD, with corresponding increases in fat, ash, and fiber content. Carbohydrate content decreased across the fortified samples, (71.44%-43.60%) reflecting a more balanced macronutrient distribution. Functional properties such as water absorption capacity and swelling index were also enhanced, indicating improved hydration and texture-related characteristics. Antioxidant properties, assessed using DPPH, ABTS, FRAP, MCA, AND PMA assays, showed a substantial increase in antioxidant activity, particularly in XYB to XYD. Phytochemical analysis indicated higher levels of flavonoids and phenols in fortified samples, confirming the functional health benefits of the added seed powder. Amino acid profile shows that Sample XYD has higher essential of 33.54% and non-essential of 49.14% amino acids to the control. This indicates enhanced protein quality and supports the nutritional benefit of fortifying traditional cereals. Sensory evaluation revealed that, although the control sample (7.92%) received the highest scores for appearance and taste, the moderately fortified sample (XYA 7.50%) maintained good overall acceptability, making it a suitable option for the development of consumer-friendly functional foods.