Tomato (Lycopersicon esculentum) is an important vegetable used in cooking most local foods in Ghana. At the peak season of harvesting, high loses are incurred because of the absence of tomato processing facilities to store, process, and extend the shelf life of fresh tomatoes. Solar drying has been proven to be a more efficient and low-cost method of enhancing quality and adding value to tomato and other vegetables. However, there are concerns about the functionality and quality of the dried products by consumers due to the methods of drying used. In this study, a passive mixed-mode solar dryer suitable for drying tomato was adapted and used to investigate the dehydration characteristics and microbiological quality of the dried tomato. The efficiency of a passive solar dryer was evaluated and used in the processing of fresh tomato to powder. The processing involved the pretreatment of 6mm slices of fresh Roma variety of tomato by dipping in potassium metabisulfite solution and ascorbic acid solution. The moisture content, moisture ratio, and dehydration rate of solar-dried tomato were assessed. The 24h dryer efficiency of 24.2 facilitated the drying process of tomato (final moisture content of 12-14). Aerobic mesophile counts were lower in solar-dried tomato pretreated with potassium metabisulfite (3.90CFU/g) compared with sun-dried samples (4.85CFU/g). Solar-dried tomato powder is safer for consumption compared with open sun-dried tomato samples.

Cocoa is a major dietary source of polyphenols, including flavanols, which have been associated with reduced blood pressure (BP). While earlier systematic reviews and meta-analyses have shown significant effects of cocoa consumption on systolic BP, limitations include small sample sizes and study heterogeneity. Questions regarding food matrix and dose of polyphenols, flavanols, or epicatechins remain. This systematic review and meta-analysis aimed to investigate the effects of ≥2 weeks of cocoa consumption as a beverage or dark chocolate in those with normal or elevated (< or ≥130 mmHg) systolic BP measured in the fasted state or over 24-h. A systematic search conducted on PubMed and Cochrane Library databases up to 26 February 2022 yielded 31 suitable articles. Independent of baseline BP, cocoa consumption for ≥2 weeks was associated with reductions in systolic and diastolic BP (p < 0.05, all). Compared with cocoa, chocolate lowered the weighted mean of resting systolic BP (−3.94 mmHg, 95% CI [−5.71, −2.18]) more than cocoa beverage (−1.54 mmHg, 95% CI [−3.08, 0.01]). When the daily dose of flavanols was ≥900 mg or of epicatechin ≥100 mg, the effect was greater. Future, adequately powered studies are required to determine the optimal dose for a clinically significant effect.

A sweetpotato-based complementary food was developed in order to promote the utilization of orange-fleshed sweetpotato (OFSP) towards reduction of vitamin A deficiency in Ghana. Four blends of complementary flours made up of OFSP, millet and soybean were formulated based on the composition of the individual flours. These formulations were done to meet the nutrient requirement of babies (6 months to 3 years) in accordance with CAC requirements. Drum drying was used to process the flour blends into instant complementary foods. The most preferred formulation (50% OFSP, 15% millet and 35% soybean flours) determined through sensory evaluation was assessed for some nutrients and microbial safety. It had significantly (p < 0.05) higher protein (16.96%) and β-carotene (0.53 mg/100g) content than the control complementary foods. Ash and fat were comparable to that of a commercial complementary food. In addition, it had a significantly higher iron and potassium content compared with weanimix and a commercial complementary food (CCF). Yeast and mould was <3 log₁₀ cfu/g, Total Plate Count, <5 log₁₀ cfu/g, while Escherichia coli and Staphylococcus aureus were not present. This indicates the product is safe for consumption. This complementary food will support efforts to reduce vitamin A deficiency in Ghana while promoting OFSP for food and nutrient security.

The potential uses of starches and flours depend on their physicochemical and functional properties. The chemical composition, functional and pasting properties of starch and flours obtained from some newly developed yam varieties from the Crops Research Institute (CRI), Ghana were evaluated, and compared with the existing local varieties. The results showed that the physicochemical and functional properties varied among the varieties studied. The CRI varieties were grouped in a principal component analysis as moisture (afase pa), amylose content (ahodenfo, soanyinto, afase biri), high starch content, bulk density and water absorption capacity (kukrupa, Mankrong pona, CRI pona). Starch pasting characteristics showed that Mankrong pona, CRI pona and afase pa exhibited stable pastes whereas afase biri, Mankrong pona and, afase soanyinto could be utilized for high-temperature processing. Overall, the new CRI varieties showed considerable functionalities that could be explored for potential food and industrial applications as compared to the existing local varieties.

Tomato (Solanum lycopersicum) is one of the most important vegetable plants in the world used in cooking foods. In Ghana, at peak seasons of harvesting tomato, high postharvest loses are incurred because of the absence of industrial tomato processing facilities for value addition into other convenient forms to extend shelf-life. Solar drying is a more efficient and low cost method of enhancing the quality and adding value to tomato. This study was carried out to design a natural mixed mode solar dryer suitable for drying tomato and to investigate the quality characteristics of the dried products. Fresh tomatoes were pre-treated with: a) 1% potassium metabisulfite solution; b) 1 % ascorbic acid solution; and c) used untreated as control. Pre-treated tomatoes were dried for three days on the average till there was no significant change in the final moisture content. Open-sun drying was used as a control for comparison purposes. The final moisture content for pre-treated solar dried and sun-dried tomato was 14 - 15 % and 19 - 22 %, respectively. The ash content was higher in the sun-dried samples compared to the solar dried samples, an indication of contamination with extraneous materials from the environment. Sulfur dioxide content of 740.8 mg/Kg d.w., for solar dried tomato pre-treated with potassium metabisulfite was much lower than the maximum legal limit of 2000 mg/Kg d.w., of sulfur dioxide recommended in fruits. Solar and sun-dried tomato pre-treated with potassium metabisulfite had significantly higher carotenoids, lycopene and beta carotene contents than pre-treated samples, and the controls. The quality of pre-treated solar-dried tomato was better enhanced by the use of the solar dryer compared to sun-drying.