Development and evaluation of the physical and nutritional qualities of extruded millet-soybean composite flour and the consumer acceptability of its instant porridge

Abstract

Malnutrition is a serious health concern in Tanzania because of its high frequency of disease and mortality. Cereal-based porridges are the most common complementary foods to children in the country. However, cereal proteins lack some essential amino acids necessary for children growth hence predisposing them to Protein Energy Malnutrition (PEM). The objective of this study was to develop and evaluate the physical and nutritional qualities of extruded millet-soybean composite flour and the consumer acceptability of its instant porridge as a food-based approach to reduce malnutrition in Tanzania. The millet and soybean were extruded and processed separately into flours which were then blended at 0, 10, 20, and 30% substitution rates for millet flour to make composite flours. The flours physical and chemical qualities as well as consumer acceptability of their porridge were evaluated using standard methods. The water absorption index (1.4 - 0.8 g/g), water solubility index (53.3 - 43.9%) and viscosity (95.10 - 5.61 dpas), of the flour slurries’ and bulk density of the flours (0.82-0.62 g/ml) significantly (p<0.05) decreased as the amount of soybean flour increased in the formulations. However, all proximate composition parameters and iron in the composite flour formulations increased with the addition of soybean flour to millet flour, with the exception of carbohydrate. The 70% millet and 30% soybean composite porridge was the most acceptable formulation by consumers. Hence, development and consumption of millet-soybean composite flour and their porridge as a food-based strategy to combat children's malnutrition in the country is highly recommended