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Capsicum fruits are commonly consumed vegetables included in foods worldwide as spices. Capsicum species are known to improve digestion and appetite, cure colds, coughs, fever, colic, dysentery, worms, and piles among others. This research is therefore aimed at evaluating the phytochemicalas well as the antioxidant activities of four different varieties of Capsicum commonly consumed in Africa. The fruits were extracted using 3 different solvents; n-hexane, ethyl acetate, and methanol. The phytochemical evaluation was carried out using standard methods. Antioxidant activities were evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The highest yield of extract was obtained with methanol from Capsicum annuum var. grossum (25.48%); The phytochemical screening of crude extracts revealed the presence of alkaloids, saponins, flavonoids, phenols, terpenoids, tannins, coumarins, and cardiac glycosides. The total phenolic contents of crude extracts of Capsicum species ranged from 25.10±0.3 to 62.01±0.1 mg GAE g-1 (Gallic acid equivalent) of dry weight and the flavonoid contents ranged from 206.08±0.03 to 474.23±0.04 mg QE g-1 (Quercetin equivalent) of dry weight. The capacity to neutralize DPPH radicals was found to be at the highest in methanolic extracts of Capsicum species which neutralized 50% of free radicals at the concentrations of 5.79 μg mL-1, 8.08 μg mL-1, 5.76 μg mL-1, and 8.81 μg mL-1for Capsicum annuum var. accuminatum, Capsicum frutescens var. baccatum, Capsicum annuumvar. grossum and Capsicum annuum var. abbreviatum respectively. The study has concluded that Capsicum species contain phytoconstituents with high antioxidant activities and great potential to combat oxidative stress and other related diseases.

Vitamin A deficiency is a public health problem in Nigeria, hitting the people in the savannah zones the hardest. This has accounted for child mortality and blindness. Therefore, there is a need to develop vitamin A rich food that is affordable and appealing to consumers. Orange-Fleshed Sweet Potato (OFSP) (Ipomoea batatas) is a variety of sweet potato now emerging as an important root crop with the possibility of tackling the problem of vitamin A deficiency. In this study, the physicochemical properties and sensory quality of Kunun-zaki, a non-alcoholic beverage sweetened with OFSP syrup, was compared to the same beverage sweetened with sugar and sugar syrup (100 mL/10 g of sweetener). The result of the physicochemical properties showed that the kunun-zaki samples were not significantly different in their pH and total titratable acidity; with values ranging from 3.93 to 4.0 and from 0.18 to 0.20 g/100 mL, respectively. The kunun-zaki samples were however significantly different in their obrix content. The OFSP sweetened sample recorded the highest obrix value of 15.20o, followed by the sugar sweetened kunun-zaki sample (13.30o) and the sugar syrup sweetened kunun-zaki (11.63o). The result of the sensory analysis showed that the sample sweetened with OFSP syrup had the best sensory attributes. The OFSP sweetened sample also had the best evaluated sensory attributes (colour, flavour, texture, and overall acceptability). The result of this study showed that Kunun-zaki sweetened with OFSP syrup was highly acceptable and could therefore serve as a dietary means of alleviating vitamin A deficiency, especially in the northern part of Nigeria where the local beverage is mostly consumed.

Malnutrition resulting from low protein intake is one of the nutritional problems facing most developing countries including Nigeria. Most proteinaceous food sources are costly and in short supply. 'Wara' is a proteinaceous ready to eat food product made by curdling milk. It does not normally undergo any further safety treatments before consumption. Frequent hawking on our major streets and roads calls for determination of the safety of these products. 'Wara' samples sourced from four different locations each at Ilorin, Kwara State and at Ogbomoso, Oyo State respectively, were analysed for nutritional and microbial safety. Proximate composition of the samples over the period of storage showed that moisture content and carbohydrates increased from 59.69% to 72.00% and from 2.39% to 11.39% respectively, while protein, fat and ash contents reduced from 22.20% to 10.80%, 15.80% to 3.62% and from 2.99% to 0.25%, respectively. Microbial and fungal counts ranged from 2.0 X 102cfu to 6.3 X 105cfu and from 2.0 X 102cfu to 7.1 X 105 cfu, respectively. Klebsiellaand Salmonella species, Escherichia coli and some fungiwere isolated. The study revealed that some of the hawked cheeses were not safe for consumption. Attributable reasons were unhygienic practices of the hawkers or producers and/or lack of requisite preservatives.

Akara (deep-fat fried balls) prepared from cowpea (Vigna unguiculata) paste is widely consumed in West Africa as a cheap source of protein. Jack bean (Canavalia ensiformis) is also rich in protein but is under-utilized in many parts of Africa due to the presence of several anti-nutritional factors. Jack bean was therefore subjected to different pre-processing methods (cracked-soaked, cracked-boiled and germinated) to reduce the anti-nutritional content before conversion into flours. Composite blends of the pre-processed jack beans and cowpea flour in different proportions of 95:05, 90:10, 85:15, 80:20 and 50:50 for each of the pre-processing methods was used in the production of akara. The proximate, pasting, functional and anti-nutritional properties of the flours as well as the proximate and anti-nutritional properties of the akara were determined using AOAC methods. The protein content of the cracked-boiled jack bean with 50% cowpea composite flour was the highest (23.65%), while germinated jack bean composite flour with 80% cowpea flour had the lowest (20.85%). Similarly, the protein content of the akara balls produced from cracked-boiled jack bean with 50% cowpea composite flour had the highest protein value (13.15%). Generally, the functional properties, except for water and oil absorption capacities were higher in cracked-boiled than in cracked-soaked and germinated jack bean composite flours. The pre-processing methods significantly (p ≤ 0.05) affected the pasting properties of the composite flours, while the anti-nutritional factors such as protease inhibitor and saponins were not detected in the akara balls. Germination of jack bean decreased tannin content than cracked-boiled and cracked-soaked, while soaking decreased the phytates levels than germination and boiling methods. Sensory attributes of the akara were significantly different (p≤ 0.05) from each other with the germinated jack bean composite flour with 50% cowpea flour having the highest rating for all the attributes measured.

Ogi has the tendency to spoil because of its high moisture content, however the reduction in moisture content through drying can enhance the shelf life, provide convenience and allow for easy reconstitution of the Ogi powder. Foaming, proximate and sensory attributes of foam-mat dried Ogi prepared from sorghum, millet and maize were studied. Each of the cereal mixed with different concentration (5%, 10% and 15%) of foaming agent; glyceryl monostearate (GMS) were whipped and the resulting foam were air dried at 60°C. Cabinet dying was also used to dry the Ogi slurry. The foam densities, proximate and sensory properties were determined using standard methods. Higher foaming agent concentration and longer whipping time resulted in lower foam densities. Foam-mat dried millet Ogi powder had higher foam density than foam-mat dried sorghum and maize Ogi powder. Generally, foammat dried Ogi powder had lower moisture content than cabinet dried Ogi, while foam mat dried Ogi had increased fat, protein and ash content with an increase in foaming agent concentration. The crude fiber of the samples varied significantly among the samples while the carbohydrate content decreased with an increase in foaming agent concentration. Freshly prepared Ogi and foam mat dried Ogi powder had comparable sensory attributes but both fresh and foam-mat dried Ogi powder had better sensory properties than cabinet dried samples.