Effect of different processing conditions on proximate and bioactive contents of Solanum aethiopicum (Shum) powders, and acceptability for cottage scale production

The purpose of this study was to investigate the effects of different processing conditions for production of dried Solanum aethiopicum (S.) leaf powder by comparing solar drying and cabinet drying processing techniques. Four (4) pre-treatments were done on S. aethiopicum leaves to inhibit enzyme action and prolong storage life. Treatments included dipping in; 10% saline solution, 10% vinegar solution, water (as the control), and steam blanching; done for both whole and sliced S. aethiopicum leaves. Each of the resultant samples were dried in both solar and cabinet dryers for a period of 24 hours. The dried leaf samples were grounded into powder using a coffee grinder and subjected to different laboratory analyses including; catalase activity, moisture content, vitamin C retention capacity and phytate content analyses. The results obtained were analysed using MINITAB version 16.0 at 5% significance level. The results showed that there was a reduction in catalase activity after pre-treatment and drying from 5.0±0.0 cm3 for the fresh un-treated leaves to a range of 4.5±0.7 – 3.0±0.0 cm3 for whole solar dried; 4.5±0.7-4.0±0.0 cm3 for sliced solar dried; 4.0±0.0 - 3.0±0.0 cm3 for whole cabinet dried and 3.5±0.7-2.3±0.7 cm3 for sliced cabinet dried leaf powder. Solar dried S. aethiopicum leaf powder contained significantly high moisture content than hot air cabinet dried one (24.9±0.5 % for saline treated sliced leaves to 8.9±0.8 % for blanched sliced leaves, than hot air cabinet dried one with 9.3±0.0 % for sliced plain water treated leaves to 7.0±0.2 % for sliced vinegar treated leaves; respectively). Cabinet dried S. aethiopicum contained significantly more vitamin C content (1.1±0.2 mg for whole blanched leaves compared to 0.6±0.1 mg for sliced vinegar treated leaves) than the solar dried one (1.0±0.2 mg for sliced plain water treated leaves to 0.6±0.1 mg for sliced vinegar treated leaves). There was no significant difference in phytate content between the hot air cabinet dried and solar dried i.e. 0.7±0.1 - 0.2±0.1 mg for solar and 0.7±0.1 - 0.3±0.3 mg for cabinet dried. Solar dried S. aethiopicum powder contained significantly higher catalase than the hot air cabinet dried one (4.5±0.7 - 3.0±0.0 and 4.0±0.0 - 2.5±0.7 cm3; respectively). However, in terms of acceptability, there was high preference for saline treated leaf powder soups compared to other soups. It can be concluded that High activity of catalase, moisture retention and high loss of Vit.C occurs in the solar drier than in cabinet drier. Whole leaf saline pretreated leaf powder soup is rated high compared to other dried soups. Therefore, the best method for production of dried S. aethiopicum powder is by slicing, dipping it in plain water and drying using a cabinet dryer. Under circumstances where cabinet drying is not achievable, solar drying is recommended using whole leaf, pretreated with saline water to promote preservation and consumption of the vegetable

Amaranth Leaves and Skimmed Milk Powders Improve the Nutritional, Functional, Physico-Chemical and Sensory Properties of Orange Fleshed Sweet Potato Flour

Vitamin A deficiency (VAD) and under nutrition are major public health concerns in developing countries. Diets with high vitamin A and animal protein can help reduce the problem of VAD and under nutrition respectively. In this study, composite flours were developed from orange fleshed sweet potato (OFSP), amaranth leaves and skimmed milk powders; 78:2:20, 72.5:2.5:25, 65:5:30 and 55:10:35. The physico-chemical characteristics of the composite flours were determined using standard methods while sensory acceptability of porridges was rated on a nine-point hedonic scale using a trained panel. Results indicated a significant (p < 0.05) increase in protein (12.1 to 19.9%), iron (4.8 to 97.4 mg/100 g) and calcium (45.5 to 670.2 mg/100 g) contents of the OFSP-based composite flours. The vitamin A content of composite flours contributed from 32% to 442% of the recommended dietary allowance of children aged 6–59 months. The composite flours showed a significant (p < 0.05) decrease in solubility, swelling power and scores of porridge attributes with increase in substitution levels of skimmed milk and amaranth leaf powder. The study findings indicate that the OFSP-based composite flours have the potential to make a significant contribution to the improvement in the nutrition status of children aged 6–59 months in developing countries

Production of nutrient‐enhanced millet‐based composite flour using skimmed milk powder and vegetables

The aim of this study was to develop a nutrient‐enhanced millet‐based composite flour incorporating skimmed milk powder and vegetables for children aged 6–59 months. Two processing methods were tested to optimize nutrient content and quality of millet‐based composite flour, namely germination for 0, 24 and 48 hr and roasting at 80, 100, and 140°C. The amount of ingredients in the formulation was determined using Nutri‐survey software. Germinating millet grains for 48 hr at room temperature significantly (p < 0.05) increased protein content (9.3%–10.6%), protein digestibility (22.3%–65.5%), and total sugars (2.2%–5.5%), while phytate content (3.9–3.7 mg/g) decreased significantly (p < 0.05). Roasting millet grains at 140°C significantly (p < 0.05) increased the protein digestibility (22.3%–60.1%) and reduced protein (9.3%–7.8%), phytate (3.9–3.6 mg/g), and total sugar content (2.2%–1.9%). Germinating millet grains at room temperature for 48 hr resulted in millet flour with the best nutritional quality and was adopted for the production of millet‐based composite flour. Addition of vegetables and skimmed milk powder to germinated millet flour significantly (p < 0.05) increased the macro‐ and micronutrient contents and the functional properties of millet‐based composite flour. The study demonstrated that the use of skimmed milk powder and vegetables greatly improves the protein quality and micronutrient profile of millet‐based complementary foods. The product has the potential to make a significant contribution to the improvement of nutrition of children in developing countries

Production of nutrient-enhanced millet-based composite flour using skimmed milk powder and vegetables

The aim of this study was to develop a nutrient-enhanced millet-based composite flour incorporating skimmed milk powder and vegetables for children aged 6–59 months. Two processing methods were tested to optimize nutrient content and quality of millet-based composite flour, namely germination for 0, 24 and 48 hr and roasting at 80, 100, and 140°C. The amount of ingredients in the formulation was determined using Nutri-survey software. Germinating millet grains for 48 hr at room temperature significantly (p < 0.05) increased protein content (9.3%–10.6%), protein digestibility (22.3%–65.5%), and total sugars (2.2%–5.5%), while phytate content (3.9–3.7 mg/g) decreased significantly (p < 0.05). Roasting millet grains at 140°C significantly (p < 0.05) increased the protein digestibility (22.3%–60.1%) and reduced protein (9.3%–7.8%), phytate (3.9–3.6 mg/g), and total sugar content (2.2%–1.9%). Germinating millet grains at room temperature for 48 hr resulted in millet flour with the best nutritional quality and was adopted for the production of millet-based composite flour. Addition of vegetables and skimmed milk powder to germinated millet flour significantly (p < 0.05) increased the macro-and micronutrient contents and the functional properties of millet-based composite flour. The study demonstrated that the use of skimmed milk powder and vegetables greatly improves the protein quality and micronutrient profile of millet-based complementary foods. The product has the potential to make a significant contribution to the improvement of nutrition of children in developing countries

Effect of skimmed milk and vegetable powders on shelf stability of millet-based composite flour

BACKGROUND: Millet porridge is a major complementary food used in Uganda but it is limited in protein and micronutrientssuch as zinc and beta-carotene. Addition of milk and vegetable powders are known to greatly improve the nutrient content ofmillet flour. However, there was limited information on the shelf stability of the resultant composite flour. This study aimed atassessing the effect of milk and vegetable powders on the shelf stability ofmillet-based composite flour.RESULTS: There was a general increase in the moisture content, peroxide value (PV), free fatty acids (FFA), thiobaturic acid(TBA) and total plate count (TPC) of both composite and millet flours over the eightweeks storage period. However, highermoisture content, PV, FFA, TBA and TPC values were recorded in the composite flour compared to millet flour (control) at eachsampling interval. Sensory evaluation results revealed that panelists preferred porridges prepared from millet only comparedto those fromcomposite flour. The degree of liking of porridges fromboth composite andmillet flours generally decreased overthe storage period.However,bothporridgesweredeemedas acceptableby the endof the storage period. The TPC also remainedbelow 105 cfu g−1 which is the maximum limit recommended by the Uganda National Bureau of Standards (UNBS).CONCLUSION: The study findings indicated that the addition of milk and vegetable powders negatively affected the stabilityof the composite flour.We recommend further studies to stabilize the product during storage.© 2018 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society ofChemical Industry

The Potential of Sweetpotato as a Functional Food in Sub-Saharan Africa and Its Implications for Health: A Review

Increasing urbanization in developing countries has resulted in busier lifestyles, accompanied by consumption of fast foods. The consequence is an increased prevalence in noncommunicable diseases (NCDs). Food-based approaches would be cheaper and more sustainable in reducing these NCDs compared to drugs, which may have side effects. Studies have suggested that consuming functional foods could potentially lower NCD risks. Sweetpotato is regarded as a functional food because it contains bioactive compounds. Recently, sweetpotato has gained attention in sub-Saharan Africa (SSA), but research has focused on its use in alleviating micronutrient deficiencies such as vitamin A deficiency, particularly the orange-fleshed variety of sweetpotato. Some studies conducted in other parts of the world have investigated sweetpotato as a functional food. There is a need to characterize the sweetpotato varieties in SSA and determine how processing affects their bioactive components. This review highlights some of the studies conducted in various parts of the world on the functionality of sweetpotato, its bioactive compounds, and how these are influenced by processing. In addition, the potential health benefits imparted by sweetpotato are expounded. The knowledge gaps that remain in these studies are also addressed, focusing on how they can direct sweetpotato research in SSA

Household Processing Methods and Their Impact on Bioactive Compounds and Antioxidant Activities of Sweetpotato Genotypes of Varying Storage Root Flesh Colours

Sweetpotato storage roots, peeled and unpeeled, of varying flesh colours (white, cream, yellow, pale orange, deep orange, and purple) were spectrophotometrically evaluated for their bioactive compounds and antioxidant activities. Roots were boiled, steamed, baked, fried, or microwaved. The unpeeled roots had relatively higher (p p < 0.001), except the deep-orange-fleshed genotype, in which frying slightly increased carotenoids from 269.81 to 304.74 µg/g. Microwaving retained 69% vitamin C in the cream-fleshed one, the highest among the cooking methods. Anthocyanins decreased with baking and frying in the purple-fleshed one but increased with other methods; microwaving being highest at 13.9% (17.43 mg/g). While the 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid antioxidant activity decreased with all cooking techniques in some genotypes, ferricyanide-reducing antioxidant potential increased. The retention of bioactive compounds in sweetpotato storage roots depends on the processing method. Thus, to obtain the most health benefits, consumers should use different cooking methods but retain the peels

Evaluating affordability of healthier diets in four African countries

Between 702 and 828 million people around the world were affected by hunger in 2021. The prevalence of undernourishment relentlessly continues to affect the world, and particularly Sub-Saharan Africa (23.2% in 2021). Exacerbated inequalities across and within countries are undermining the nutritional adequacy and affordability of diets and threatening vulnerable groups including children under five years of age and women of reproductive age. This research presents a diet optimization approach where the objective is to evaluate the nutritional adequacy and affordability of diets across 4 African countries, namely Ethiopia, Kenya, South Africa and Uganda. The targeted population includes dyads of women of reproductive age and their children between 6 and 24 months. The mathematical programming approach allows for the theoretically contrasting of optimal outcomes of the model with data from food consumption surveys in primary and secondary cities of each country. Based on the observed food intake patterns and the nutrient deficiencies, these outcomes propose new diets modifying food intake (organized in food groups) in order to achieve nutritional adequacy while minimizing food intake changes, or, if applicable, the outcomes indicate which nutrient recommendations are unattainable under the current model setup. On average, our results show that nutritional adequacy can be attained by increasing the intake of legumes, vegetables and fruits, while reducing the intake of cereals. We include a discussion on the assessment of diet affordability and show the practical implications of evaluating healthier diets’ viability. Conclusions include paths for future research on diet optimization modelling and its implications as a means of support for designing future dietary guidelines