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This study evaluated the effects of fortification of a popular maize porridge (ogi) with the extract of fluted pumpkin leaves. This was with a view to increasing the functionality of the food. Ogi cake was produced via a traditional wet milling process of steeped maize grains. The fluted pumpkin liquid extract was obtained by squeezing the fluted pumpkin leaves in warm water (50°C) in the ratio 1:2 (w/v) for 10 min. The mixture was sieved with double-layered muslin cloth to obtain the liquid extract. The extract was added to ogi cake in the following proportions; 10:100, 25:100, 50:100, 75:100 and 100:100 mL g(-1) of extract to cake to make ogi-extract suspensions. The suspensions were dried at 55°C and milled to obtain ogi powder. The proximate composition, functional properties, some mineral elements, vitamin C content, total phenolic contents (TPC), total flavonoid contents (TFC), anti-radical activity (DPPH), viscosity and sensory evaluation were examined. The addition of fluted pumpkin leaf extract resulted in 83.33 to 1367%, 75 to 325% and 5.43 to 90.05% increase in protein, ash and vitamin C content, respectively. An increase of 64.29 to 803.57%, 12.08 to 71.07% and 32.39 to 110.35% were respectively recorded for TFC, TPC and DPPH activity. Calcium, potassium, sodium, iron and phosphorus increased by 55.23 to 760.58%, 24.69 to 398.49%, 196.43 to 2801.79%, 33.33 to 1150% and 100.38 to 3139%, respectively. Viscosities of the green porridge ranged between 50.72 to 80.84 mPa s. The results for sensory evaluation showed that addition of extract up to 75 mL were accepted by the consumers. The addition of fluted pumpkin leaf extract resulted in the improvement of the nutritional profile without alteration to the aesthetic values of the food apart from colour which would not be a detriment with time and awareness.

Increased efficiency and productivity in agriculture are important to food security. Technical efficiency, as it affects sustainable production of selected underutilized indigenous vegetables, using innovative production practices or not, was analyzed. Primary data were collected from 300 respondents using questionnaires. The data were interpreted with a stochastic production frontier analysis and difference of means. A mean technical efficiency score of 74% for users versus 56% for nonusers incorporating innovative production practices in their operations indicated that users were more technically efficient. Opportunities exist to increase productivity in indigenous vegetable production through more efficient inputs utilization.

The aim of this work was to determine the antioxidant properties of aqueous extracts of vegetable leaf-fortified bread as well as estimate the contents of polyphenolic compounds. Enriched bread was produced from wheat flour fortified at 1, 2, and 3% (w/w) with dried leafy vegetable powders from Amaranthus viridis, Solanum macrocarpon, and Telfairia occidentalis. Gallic acid was the most abundant soluble polyphenol in the control bread and the content in the control bread was significantly higher (p < 0.05) than in all the fortified bread samples. Fortification of bread especially at 3% level resulted in significantly (p < 0.05) higher concentrations of other polyphenols (myricetin, catechin, quercetin, and rutin) compared to the control bread. The fortified bread extracts had significantly (p < 0.05) more effective antioxidants than the control for DPPH radical scavenging activity, ferric iron reducing antioxidant power, metal chelation, and inhibition of linoleic acid peroxidation. PRACTICAL APPLICATIONS: Bread is one of the consumed foods and could be used as a suitable carrier of bioactive compounds. Leafy vegetables contain high levels of polyphenols that could provide beneficial effects by contributing to improved health status of consumers. Therefore, incorporation of leafy vegetables into leavened bread could provide a means of enhancing polyphenol consumption. In this work, we showed that soluble polyphenols were enriched in vegetable-fortified bread. The polyphenol-rich extracts of the fortified bread demonstrated better free radical scavenging and inhibition of unsaturated fatty acid oxidation activities than the regular bread. Therefore, regular consumption of vegetable leaf-fortified bread could lead to reduced oxidative stress and associated chronic diseases in human beings. The vegetable leaf fortification could also serve as a suitable means of enhancing the shelf life of wheat bread.

Optimization of the yield, total phenolic content (TPC), and total antioxidant activities (TAA) of polyphenol concentrates extracted from Solanum macrocarpon leaves was studied using response surface methodology. The process variables investigated included extraction temperature (30, 50, and 70°C), extraction time (2, 4, and 6 h), and dried leaf powder : water ratio (1 : 10, 1 : 20, and 1 : 30 w/v). Box–Behnken design resulted in 15 experimental runs. The results showed the following optimum extraction conditions: temperature, 49.05°C; extraction time, 243 min; leaf powder : water ratio, 1 : 22 w/v. The optimized extraction conditions gave polyphenol concentrate yield, TPC, and TAA values of 24.94%, 421.09 mg GAE/g, and 23.81 mg AAE/g, respectively. Results of the in vitro antioxidant activities of the polyphenol concentrate showed 2, 2-diphenyl-2-picrylhydrazyl hydrate, metal chelating ability, and ferric reducing ability values of 76.78%, 80.22%, and 56.46 mg AAE/g, respectively. The study concludes that the experimental values compared closely with the predicted values, which indicates suitability of the model employed for polyphenol extraction optimization from dried S. macrocarpon leaves.

We quantified the impact of new production technologies on total land area allocated to production of six (ugu, igbagba, tete atetedaye, woorowo, ogunmo and odu) selected high-premium under-utilised indigenous vegetables (UIVs) in south-western Nigeria. Leaf yields and accruable returns were estimated by comparing the data for these parameters at the commencement of the project in 2011 (through a baseline survey) with the same set of parameters after three years (in 2013) of project implementation. Through a structured interview and focus group discussion involving 134 randomly selected respondents (59 women and 75 men) from the 350 UIVs cooperative members in the rainforest and derived savanna agroecologies in four states (Oyo, Ondo, Osun and Ekiti) of south-western Nigeria, we studied the gender gap between male and female farmers with respect to access to productive farm resources. The data obtained were analysed using appropriate descriptive and inferential statistics. On average across south-western ...

The study evaluated the effects of six pretreatment methods before cooking on the peroxidase activity, chlorophyll and antioxidant profile of Amaranthus cruentus L. and Solanum nigrum L. The six pretreatments used were: chopped only (raw sample) (Coded Ml); chopped and dried at 50oC for 5 hours(Coded M2); chopped and squeezed in water (at room temperature) (Coded M3); chopped and soaked in salt-treated water (approx. 20 g NaCl per L of water) for 15 mins, then squeeze (Coded M4), chopped and soaked in warm water (approx. 60oC), then cool and squeeze (Coded M5); and chopped and soaked in boiling water (100oC), then cool and squeeze (Coded M6). The main effect of vegetable type and the main effect of pretreatment methods have significant effects (P< 0.05) on the parameters measured while the interaction of vegetable type and pretreatment methods have no significant effect on the parameters measured. Statistical analyses (p< 0.05) showed that chlorophyll "a" and "b" occur in ratio 3:1 in the two vegetables irrespective of the pretreatment imposed. Peroxidase activity test showed that A. cruentus, irrespective of the pretreatment imposed showed no peroxidase activity while S. nigrum showed high peroxidase activity for all the pretreatments except for M6. Results showed tha: there was significantly (P