Optimization of germinated cowpea flour ratios and extrusion conditions on the nutritional composition and sensory quality of Ethiopian emmer wheat-based extruded porridge

Abstract

Childhood malnutrition is a major problem in developing countries, particularly in Ethiopia. This study aimed to create nutritious emmer wheat and cowpea extruded porridge with optimal macronutrient levels and sensory quality. Utilizing Design-Expert software, the effects of cowpea blending ratios (10–25 %), barrel temperatures (80–120 °C), and feed moisture content (22–26 %) were analyzed using a three-factor, three-level Box-Behnken design. Significant impacts on nutritional characteristics were observed, leading to the identification of optimal extrusion conditions (cowpea blend: 20.17 %, moisture content: 25.91 %, barrel temperature: 117.20 °C). Blending emmer wheat with cowpea flour significantly enhanced the porridge's color, taste, and aroma. The highest color intensity (4.36 %) was at 10 % cowpea and 22 % moisture processed at 100 °C. The best taste (4.41 %) was with 25 % cowpea and 22 % moisture at 100 °C, while the highest aroma was in blends with 10 % and 25 % cowpea at 100 °C. The control had the best mouthfeel (4.36 %), but a blend with 25 % cowpea, 24 % moisture, and 80 °C barrel temperature had the highest overall acceptability (4.31 %). The study highlighted the potential of these protein-rich porridge products to address protein-energy malnutrition, particularly in Ethiopia, by introducing awareness about the unique nutritional composition of Ethiopian emmer wheat and underutilized cowpea, thus creating a new market for nutritious food options.