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The value chains of African indigenous vegetables (AIVs) are highly constrained by high postharvest losses (up to 50%) along the chain, largely occasioned by poor postharvest management and a lack of optimized processing technologies. The technologies and practices are key technical aspects that can transform the capacity of the chain by enhancing the overall value generated from the system. AIVs have recently experienced an increase in demand due to their high nutritional value and the opportunity they present to enhance rural incomes, since they are predominantly produced by smallholder farmers in rural and peri-urban areas. This implies that they can positively contribute to increased availability and hence supply of nutritious food within local food systems. Furthermore, the fact that half of the economic value of AIVs is potentially lost due to inappropriate postharvest management and inadequate processing demonstrates the potential that related interventions and transformations could have in enhancing and preserving value along AIV value chains. Currently, the approaches applied to reduce food waste, preserve nutritional quality, and add value to AIVs are largely traditional in nature. They require upgrading and need to be aligned toward achieving a nutrition-sensitive value chain. By looking at these as value creation processes, this mini-review examines the current postharvest management practices, highlights relevant new and innovative technologies and related challenges, and suggests potential options to improve the benefits for AIV value chain actors and thus contribute to a sustainable transformation of nutrition-sensitive food systems.

Micronutrient deficiency (MD) is a problem among schoolchildren which, in addition to other effects, also affects their intellectual abilities. Inclusion of vegetables to food formulations can help to reduce MD because they contain vital micronutrients which are required for improved school performance. This study aimed at evaluating acceptability, determining the nutritional quality and estimating the contribution of vegetable enriched products to the Recommended Dietary Allowance (RDA) of schoolchildren (5 to 13 years). The vegetables used were red and green amaranth leaves, orange fleshed sweet potato and pumpkin. Selection of vegetables was based on richness in micronutrients; local availability and consumption levels in Uganda; and their underutilization status particularly in processed form. Each of the vegetables was preprocessed and incorporated separately into soybean and grain amaranth in the ratio of 10:40:50, respectively, to improve the nutrient and energy density of the formulations. Sensory screening of formulations in a range of products (porridges, soups and snacks) revealed that orange fleshed sweet potato formulation was most preferred for porridge as well as for snacks (at 30:70 ratio of orange fleshed sweet potato composite to wheat flour); while red amaranth leaves composite was most preferred for soup. When tested for acceptability, nutritional quality, as well as contribution to the RDA (for vitamin A, iron, zinc, protein and energy) for schoolchildren 5 to 13 years, acceptability tests and nutritional quality of food products from the formulations were highly rated compared to commercial products (pure maize porridge, wheat based soup and 100% refined wheat flour snacks). All products from the two formulations contributed favourably to vitamin A, iron, zinc and protein requirements of children (5 to 13 years). Based on these findings, orange fleshed sweet potato composite flour can be recommended for making porridge, and can substitute (30%) for wheat flour in making snacks; while red amaranth leaf composite flour can be recommended for making soups.

Wild seasonal edible insects such as Ruspolia differens continue to significantly contribute to the food, nutrition and economic security of many people in Uganda and Africa at large. This research aimed at investigating the effect of season, sourcing geographical area and processing method on the nutrient profile of R. differens. On a dry matter basis, proteins (34.2–45.8%), lipids (42.4–54.3%) and chitin (8.26–10.79%) were the most abundant macronutrients while potassium (242.0–673.3 mg/100 g), phosphorus (316.1–626.6 mg/100 g), calcium (34.9–128.0 mg/100 g), magnesium (38.5–69.0 mg/100 g) and iron (33.2–69.0 mg/100 g) were the most abundant micronutrients. Vitamin B12 ranged from 0.22–1.35 μg/100 g. The full amino acid profile was determined, showing a high biological value. The variability in amino acid composition across the different samples (areas, seasons) was low. Oleic acid (C18:1 cis-9) was the most abundant (38.9–42.7%) fatty acid, followed by palmitic acid (C16:0) (26.6–28.5) and linoleic acid (C18:1 cis-6) (17.6–23.0%), implying that the R. differens fat is highly unsaturated (56.5–65.7%), similar to chicken and pork but higher than beef. R. differens samples from the April season had a significantly higher protein and mineral content than samples from the December season, probably due to the younger growth stage of the grasshoppers. Geographical area also significantly influenced the nutrient content of R. differens but not consistently. Boiling and roasting significantly resulted in the loss of lipids, minerals and vitamin B12. Correspondingly, protein content increased. Understanding the nutrient profile of R. differens will greatly contribute to defining its key quality attributes and inform development of shelf stable products fit for the formal regulated market. Despite R. differens’ potential to contribute to combatting the micro and macro nutrient deficiencies especially for protein and iron, the bio-availability of these nutrients need to be investigated. Efforts to rear R. differens should be harnessed to ensure its sustainable contribution to food, nutrition and income security. ispartof: Global Food security and food safety: the role of universities ispartof: Tropentag location:Gent date:17 Sep - 19 Sep 2018 status: published

Metadata only record Grain amaranths (Amaranthus spp.) are high protein content and protein quality pseudo-cereal crops whose favorable nutritional profile belies their potential to alleviate nutrition and food insecurity in developing countries. Grain amaranth was introduced as a nutrient dense food into the Kamuli District, eastern Uganda, in 2006. However, initial analysis of protein content of amaranth grain pooled from farms in the Kamuli District indicated that protein levels ranged from 11.7% to 12.5%, lower than the average value of 15% found in the literature. Based on previous surveys of amaranth production practices in the area, this study was designed to determine: 1) variability of amaranth grain yields and protein content between farms; 2) variability of amaranth grain yields and protein content between varieties; and 3) the effects of soil physical and chemical properties, and the use of organic soil amendments, on amaranth grain yields and protein content. On-station and on-farm trials were conducted to determine the effects of organic soil amendments on amaranth grain yield and protein content. The on-station trials were conducted during 2009 in Wakiso District in south-central Uganda, to test effects of poultry manure and composted manure, while on-farm trials took place on ten farms during the short rainy season of 2009 in Kamuli District to determine the effects of cattle manure on the aforementioned parameters. On-station grain amaranth trials were conducted twice, during both the dry and short rainy seasons, and tested the effect of poultry manure and composted manure applied at 0, 1, 1.5, and 3 ton ha-1 on amaranth varieties “cream”, “golden” and ‘Plainsman’. There were no significant differences between amendment treatments for either trial, however, mean grain yields for the rainy season were higher at 1886 kg ha-1 compared to 1110 kg ha-1 for the dry season. Concerning varietal differences, yields for “cream” and “golden” varieties were significantly greater than those for ‘Plainsman’ during the dry season, whereas in the rainy season “cream” yields were significantly greater than those for “golden” and ‘Plainsman’. Amaranth grain was pooled across all treatments and varieties to determine a protein content of 14.5% and 15.1% for the dry and rainy seasons, respectively. For the on-farm trials, yields were lower than in the on-station trials and were significantly different between farms. Application of cattle manure provided a significant yield increase. While there were no significant differences between varieties, amaranth grain protein content was significantly different between farms. Average protein content of 14% across treatments and varieties revealed a greater amaranth protein content than previously reported for Kamuli District. LTRA-10 (CAPS for smallholder farms in eastern Uganda and western Kenya) CCRA-9 (Soil Quality and Soil Carbon Sequestration)