Purpose Child undernutrition is a persistent problem in Africa, especially in areas where the poor largely depend on starchy staples with limited access to diverse diets. The purpose of this study was to determine the protein quality, growth and rehabilitating potential of composite foods made from quality protein maize. Design/methodology/approach Four composite diets were prepared from quality protein maize, namely quality protein maize-soybeans; quality protein maize-soybeans-cowpeas; quality protein maize-soybeans-common beans and quality protein maize alone. A fifth diet was prepared from common maize alone. The control diet (Chesta®) was made from maize, soybeans, fish, bone and blood meal. The formulations were made to meet the greatest amino acid score and the desired amount of energy and fat according to the FAO/WHO (1985) recommendation for pre-school children. Albino rats were used in evaluating the protein quality of the formulations. Findings The food intake was significantly different (p < 0.05) among diets; with a trend of intake decreasing from quality protein maize-based to conventional maize alone diets (apart from the control diet). Protein efficiency ratio and net protein ratio varied significantly (p < 0.05) across the experimental diets. Protein digestibility-corrected amino acid score (PDCAAS) was 80 per cent (quality protein maize-soybeans-cowpeas), 87 per cent (quality protein maize-soybeans), 103 per cent (common maize alone), 98 per cent (quality protein maize), 80 per cent (quality protein maize-soybeans-common beans) and 53 per cent (control). Research limitations/implications Two diets, namely quality protein maize-soybeans-common beans and quality protein maize-soybeans-cowpeas, showed the greatest potential to support growth and rehabilitation of undernourished rats. Human trial is proposed to validate the findings. Originality/value Despite adoption of quality protein maize in several parts of the country, there are no studies that have been done to determine the potential of quality protein maize to support optimal growth and rehabilitation of undernourished children. The objective of this study was, therefore, to evaluate the protein quality, growth and rehabilitating potential of composite foods made from quality protein maize.

No abstract

Most complementary foods used for children in Tanzania are low in energy and nutrient content. In addition, they may contain contaminants such as mycotoxins and also antinutritional factors. The aim of this study was to determine nutritional quality of quality protein maize-based supplementary foods and levels of mycotoxins (fumonisins, aflatoxins) and antinutritional factors (phytates, tannins). Three composite diets were prepared from quality protein maize namely; quality protein maize-soybeans; quality protein maize-soybeans-common beans and quality protein maize-soybeans-cowpeas. The fourth and fifth diets were prepared from plain quality protein maize and plain common maize. The formulations were made to meet the greatest amino acid scores and the desired amount of energy and protein according to the FAO/WHO (1985) recommendation for preschool children. Concentrations of energy, protein, amino acid, aflatoxins, fumonisins, phytates and tannins were determined by standard methods. Quality protein maize-soybeans-common beans and quality protein maize-soybeans-cowpeas met RDA for both energy (360 kcal/100 g) and protein (16 g/100 g) for children aged 2-5 years. The amino acid scores for QPM-based diets were higher than the recommended scores (≥65%) for supporting optimal growth of children. Concentrations of fumonisin B1 and total fumonisin were 1687.82 and of 1717.16 μg/kg in quality protein maize and 1625.08 and 1745.22 μg/kg in plain common maize, respectively. These values were above the maximum tolerable limit of 1000 μg/kg recommended by the European commission. Efforts such as good agricultural practices and proper processing of food ingredients by sorting, dehulling and washing are recommended to reduce concentrations of fumonisins in maize grains.

Maize porridge is widely consumed by children less than five years of age in Tanzania and other countries. The aim of this study was to evaluate the sensory attributes and the overall acceptability of the extruded quality protein maize-based supplementary foods for children in Tanzania. Two ready-touse supplementary foods were produced by extrusion cooking (quality protein maize-soybeanscommon beans and quality protein maize-soybeans-cowpeas) using the following food ingredients: quality protein maize, soybeans, common beans and cowpeas. Sugar, vitamins and mineral premix were added. These products were tested against a control diet made from common maize, soybeans, millet, wheat and groundnuts. A panel of sixty consumers was involved in the evaluation of sensory attributes of the porridge samples and overall acceptability was determined using 5 point Hedonic scale. Descriptive analysis was performed by 11 trained panelists using the lexicon developed. Statistical analysis was performed using analysis of variance and principal component analysis. Consumer evaluation revealed that quality protein maize-soybeans-common beans porridge was rated higher (p˂0.05) for aroma (4.6) and taste (4.6) than all porridge samples tested. Despite higher rating in aroma and taste, all the porridges (quality protein maize-soybeans-common beans, quality protein maize-soybeans-cowpeas and conventional porridge) were equally acceptable (p˃0.05) by the test panelists. Mean scores for overall acceptability of quality protein maize-soybeans-common beans, quality protein maize-soybeans-cowpeas and conventional porridge were 4.6, 4.3 and 4.2, respectively. All the three porridges were differentiated (p˂0.05) using the identified language for quantitative descriptive study. The sensory attributes of colour, oiliness, aroma, sweetness, liking and aftertaste in principal component 1 distinguished experimental porridges from the control. However, all the food products could be described by viscosity, sweetness and colour in principal component 2. This was an indication that test diets, quality protein maize-soybeans-common beans and quality protein maizesoybeans-cowpeas resembled the control diet by some attributes namely, aroma, aftertaste and sweetness and therefore, had higher potential for acceptance by consumers.

No abstract