Browsing by Author "Wireko-Manu, Faustina D."
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- ItemAntioxidant activity, total phenols and phytochemical constituents of four underutilised tropical fruits(International Food Research Journal, 2015) Boakye, Abena A.; Wireko-Manu, Faustina D.; Agbenorhevi, Jacob K.; Oduro, Ibok N.; 0000-0003-0344-2683; 0000-0002-5020-6299; 0000-0002-8516-7656; 0000-0003-3731-2684The antioxidant activity, total phenols content and phytochemical constituents of edible portions of four underutilised tropical fruits; Irvingia gabonensis (African mango), Artocarpus altilis (breadfruit), Annona muricata (soursop) and Annona squamosa (sweetsop) were determined. Extracts of fruit samples were screened for selected phytochemicals using standard methods whereas the total phenols content and antioxidant activity (by free radical scavenging action) was determined by the Folin-Ciocalteu method and DPPH assay, respectively. The antioxidant activities were high with values ranging from 63% inhibition (breadfruit) to 78% inhibition (African mango pulp). African mango seeds had the highest total phenols content (20.96 mg GAE /100g). Tannins, triterpenoids, saponins, sterols, cardiac glycosides, flavanoids and coumarins were detected in most of the fruit extracts. The study revealed that these underutilised tropical fruits have considerable free radical scavenging (antioxidant) activity and an array of phytochemicals necessary to significantly impact health of consumers.
- ItemCharacterization of pectin extracted from muskmelon (Cucumis melo L.)(Journal of Science and Technology, 2021-10) Nyarko, Benjamin; Agbenorhevi, Jacob K.; Wireko-Manu, Faustina D.; Kpodo, Fidelis M.; 0000-0002-8516-7656; 0000-0002-5020-6299; 0000-0002-7949-0502Muskmelon (Cucumis melo L.) fruits are cultivated for their seeds, but the peels are potential sources of pectin for food and pharmaceutical applications. The objective of this study was to extract and characterize pectin from muskmelon peels subjected to two different drying techniques. The pectin was extracted using acid treatment and the structure, chemical composition and functional properties determined. Oven and solar dried muskmelon pectin extracts gave comparable yields (6.48% and 5.27%), high degree of methylation (60.53 and 64.97%) and anhydrouronic acid content of 46.99% and 56.60%, respectively. Intrinsic viscosity was 0.3 gdL-1 irrespective of drying technique used. The pectin extracts from the oven and solar dried muskmelon demonstrated good water absorption (208g/100g and 269g/100g), oil absorption (237g/100g and 152g/100g) and emulsion (50% and 46%) capacities, respectively. The different drying techniques used did not significantly influence physicochemical and functional properties. The findings show that muskmelon pectin are high methoxyl pectin with good functional properties which can be tailored for use in food and pharmaceutical formulations.
- ItemChemical, functional and pasting properties of starches and flours from new yam compared to local varieties(CyTA - Journal of Food, 2022) Effah-Manu, Liticia; Wireko-Manu, Faustina D.; Agbenorhevi, Jacob K.; Maziya-Dixon, Bussie; Oduro, Ibok N.; 0000-0003-2896-9916; 0000-0002-5020-6299; 0000-0002-8516-7656; 0000-0003-2014-2201; 0000-0003-3731-2684
- ItemDevelopment and Quality Assessment of Cassava Sweetpotato Non-Alcoholic Beverage(MOJ Food Processing & Technology, 2016) Wireko-Manu, Faustina D.; Agyare, Anita; Agbenorhevi, Jacob K.; Oduro, Ibok N.; 0000-0002-5020-6299; 0000-0001-9991-0546; 0000-0002-8516-7656; 0000-0003-3731-2684Most Non-alcoholic beverages (NABs) are produced from fruits, dairy, cocoa etc.,but seldom from roots and tubers. This study aimed at producing NAB from cassava and sweetpotato roots. Four different formulations were prepared; cassava roots : sweetpotato roots - 100:0%, 90:10%, 70:30%, 50:50%. The clean, peeled, grated roots were weighed in percentages, blended and the juice extracted. The juice was allowed to stand, decanted, filtered and heated with maize malt, sugar, ginger and water and finally packaged hot. Consumer preference was done with 49 panelists and pH, total solids, total soluble solids (TSS), titratable acidity (TA) and Vitamin C were determined on all formulations. Titratable acidity ranged from 0.51 to 0.77% with the 50:50 formulation being the highest. Total solids, varied significantly and ranged from 8.96 - 12.00% and the 90:10 formulation had the highest value. Vitamin C content was low with a range from 2.43-3.99mg/100g for 100:0 and 50:50% respectively. TSS of the beverages were within 8.50 and 10.50 with the 100% having the least value. Generally, as sweetpotato percentage increased, the vitamin C content, TA, TSS increased but the pH decreased. The sensory results showed that there were no significant differences (p < 0.05) among the three different formulations that contained sweetpotato but rather significant differences in overall acceptability and taste between the control (100% cassava) and the other samples. Generally the beverage had good consumer preference with the most preferred being the 50:50% formulation. The quality parameters of all formulations were within the acceptable quality range specified by Ghana Standards Authority for beverages. The potential to use liquid extract from cassava and sweetpotato during processing for beverages is high. This could expand utilization base of the crops while reducing potential hazards of untreated water from root and tubers
- ItemDevelopment and Quality Assessment of Cassava Sweetpotato Non-Alcoholic Beverage(MOJ Food Processing & Technology, 2016) Wireko-Manu, Faustina D.; Agyare, Anita; Agbenorhevi, Jacob K.; Oduro, Ibok N.; 0000-0002-5020-6299; 0000-0002-8516-7656; 0000-0003-3731-2684Most Non-alcoholic beverages (NABs) are produced from fruits, dairy, cocoa etc., but seldom from roots and tubers. This study aimed at producing NAB from cassava and sweetpotato roots. Four different formulations were prepared; cassava roots : sweetpotato roots - 100:0%, 90:10%, 70:30%, 50:50%. The clean, peeled, grated roots were weighed in percentages, blended and the juice extracted. The juice was allowed to stand, decanted, filtered and heated with maize malt, sugar, ginger and water and finally packaged hot. Consumer preference was done with 49 panelists and pH, total solids, total soluble solids (TSS), titratable acidity (TA) and Vitamin C were determined on all formulations. Titratable acidity ranged from 0.51 to 0.77% with the 50:50 formulation being the highest. Total solids, varied significantly and ranged from 8.96 - 12.00% and the 90:10 formulation had the highest value. Vitamin C content was low with a range from 2.43-3.99mg/100g for 100:0 and 50:50% respectively. TSS of the beverages were within 8.50 and 10.50 with the 100% having the least value. Generally, as sweetpotato percentage increased, the vitamin C content, TA, TSS increased but the pH decreased. The sensory results showed that there were no significant differences (p < 0.05) among the three different formulations that contained sweetpotato but rather significant differences in overall acceptability and taste between the control (100% cassava) and the other samples. Generally the beverage had good consumer preference with the most preferred being the 50:50% formulation. The quality parameters of all formulations were within the acceptable quality range specified by Ghana Standards Authority for beverages. The potential to use liquid extract from cassava and sweetpotato during processing for beverages is high. This could expand utilization base of the crops while reducing potential hazards of untreated water from root and tubers.
- ItemDietary fibre ascorbic acid and proximate composition of tropical underutilised fruits(African Journal of Food Science, 2014-06) Boakye, Abena A.; Wireko-Manu, Faustina D.; Agbenorhevi, Jacob K.; Oduro, Ibok N.; 0000-0003-0344-2683; 0000-0002-5020-6299; 0000-0002-8516-7656; 0000-0003-3731-2684The current surge in the prevalence of chronic diseases has necessitated the call for the increased consumption of fruits to curtail the phenomenon.The dietary fibre fractions .......................................
- ItemGender-Disaggregated Consumer Testing and Descriptive Sensory Analysis of Local and New Yam Varieties(Foods, 2023) Effah-Manu, Liticia; Wireko-Manu, Faustina D.; Agbenorhevi, Jacob K.; Maziya-Dixon, Busie; Oduro, Ibok N.; 0000-0003-2896-9916; 0000-0002-5020-6299; 0000-0002-8516-7656; 0000-0003-2014-2201; 0000-0003-3731-2684Gender-disaggregated sensory evaluation has become an essential element that could enhance breeding activities by increasing the adoption of new varieties. The effect of age, sex and geographical location on descriptor preferences for boiled and pounded yam were studied using descriptive and consumer testing. Attributes with definitions and measurement scales were used to generate lexicons for boiled and pounded yam. Analytical tools employed for the inferential statistics were the independent t-test, analysis of variance, Kruskal–Wallis test, Mann–Whitney test and relative importance index (RII). Descriptive testing showed that all the D. rotundata varieties were good for boiling and pounding. The D. alata varieties afase soanyinto and afase biri were most liked, while afase pa and ahodenfo were disliked. Age had no significant effect on descriptor preferences. Being a female or male, however, influenced preferences for pounded yam descriptors such as mouldability, lumpiness and colour. The RII for the D. rotundata varieties (0.22–0.28) showed that they are all good varieties for boiling and pounding. The local D. alata varieties were still highly acceptable compared the new CRI varieties due to the aroma. Rural consumers preferred all the descriptors of boiled D. rotundata than urban consumers, whereas urban consumers liked the pounded yam varieties better than the rural consumers. Availability of the new yam varieties on local markets could therefore increase consumption and improve adoption.
- ItemImproved Yam-Baobab-Tamarind flour blends: Its potential use in extrusion cooking(Scientific African, 2019) Adams, Zeenatu Suglo; Wireko-Manu, Faustina D.; Agbenorhevi, Jacob K.; Oduro, Ibok N.; 0000-0001-9763-4023; 0000-0002-5020-6299; 0000-0002-8516-7656; 0000-0003-3731-2684This project was aimed at determining the physicochemical properties of water yam baobab-tamarind flour composites and its potential use in extrusion cooking. Proximate and mineral composition of Baobab (B), Yam (Y), and Tamarind (T) were determined. Six blends of composite flours were formulated and colour and physicochemical properties were determined. Two of the flour blends were used as trial samples and extruded. Proximate composition of B, Y and T were comparable to similar literature reports, however, the mineral compositions were low. Moisture content, pH, water binding capacity, swelling power and bulk density values ranged from 3.01-5.61%, 3.90–5.39, 87.50–132.50%, 201.43–237.95% and 0.74–0.93 g/mL, respectively, for the flour blends. Peak, minimum, cooling end, final, breakdown and setback viscosities were in the range of 2.50–291.00bu, 2.20–289.50bu, 11.00- 455.00bu, 10–440bu, 0.00–20.50bu and 69.50–148.00bu, respectively, for flour blends. The addition of tamarind and baobab flours improved the swelling power, water binding capacity and peak viscosity of flour extrudates. Generally the L, a, and b values for extrudates were lower than the flour composites. However, the panelist pre ferred the appearance. The bulk density and expansion ratio of extruded snacks were low. Generally, panellists preferred extrudates with higher (40%) tamarind kernel powder substitution (E5). The extruded composite flour (E6) had low viscosity values. Incorporation of tamarind and baobab into water yam flour has great potential for development of extruded snacks.
- ItemPackaging and Shelf Life of Maize-Peanut Balls (Dakua)(MOJ Food Processing & Technology, 2017) Osae, Abena K.; Agbenorhevi, Jacob K.; Wireko-Manu, Faustina D.; 0000-0002-8516-7656; 0000-0002-5020-6299Maize-peanut balls (also known as dakua, dzowe or donkwa) is a street snack made from roasted, dried and milled maize and groundnuts/peanuts. It is often sold unpackaged by hawkers/vendors, in a portable food booth, food cart or food truck. However, the shelf life is unknown which makes this nutritious snack also a potential risk to consumers’ health. In this study, the packaging and shelf life of maize-peanut balls (lab/self-made and those purchased from the local markets) were investigated by packaging in aluminum foil, flexible plastic films and unpackaged and stored at ambient temperature for 5 weeks. The products were analysed weekly for moisture, peroxide value, aflatoxin level, yeast and moulds during storage. Results indicate that the samples had variable moisture content, which decreased from the start of the analysis to the third week and increased again. Over the 5 weeks storage period, peroxide values increased to ~0.4 mEq/ kg. The unpackaged samples had the highest aflatoxin level (~21.74 ppb), which is above the acceptable limit of 20 ppb. The samples packaged in flexible plastic film, however, had the lowest aflatoxin level (~13.15 ppb) whereas samples packaged in aluminum foil had values of ~16.75 ppb. The estimated shelf life is approximately 8 weeks with flexible plastic films as the most suitable packaging material.
- ItemPackaging and Shelf Life of Maize-Peanut Balls (Dakua)(MOJ Food Processing & Technology, 2017) Osae, Abena K.; Agbenorhevi, Jacob K.; Wireko-Manu, Faustina D.; 0000-0002-8516-7656; 0000-0002-5020-6299Maize-peanut balls (also known as dakua, dzowe or donkwa) is a street snack made from roasted, dried and milled maize and groundnuts/peanuts. It is often sold unpackaged by hawkers/vendors, in a portable food booth, food cart or food truck. However, the shelf life is unknown which makes this nutritious snack also a potential risk to consumers’ health. In this study, the packaging and shelf life of maize-peanut balls (lab/self-made and those purchased from the local markets) were investigated by packaging in aluminum foil, flexible plastic films and unpackaged and stored at ambient temperature for 5 weeks. The products were analysed weekly for moisture, peroxide value, aflatoxin level, yeast and moulds during storage. Results indicate that the samples had variable moisture content, which decreased from the start of the analysis to the third week and increased again. Over the 5 weeks storage period, peroxide values increased to ~0.4 mEq/kg. The unpackaged samples had the highest aflatoxin level (~21.74 ppb), which is above the acceptable limit of 20 ppb. The samples packaged in flexible plastic film, however, had the lowest aflatoxin level (~13.15 ppb) whereas samples packaged in aluminum foil had values of ~16.75 ppb. The estimated shelf life is approximately 8 weeks with flexible plastic films as the most suitable packaging material.
- ItemThe effect of gender on end-user preferences for yam quality descriptors(Food Science and Nutrition, 2022) Effah-Manu, Liticia; Wireko-Manu, Faustina D.; Agbenorhevi, Jacob K.; Maziya-Dixon, Bussie; Oduro, Ibok N.; Baah-Ennum, Theresa Y.; 0000-0003-2896-9916; 0000-0002-5020-6299; 0000-0002-8516-7656; 0000-0003-3731-2684; 0000-0003-1572-2076Improving the effectiveness of breeding programs could be achieved by breeding for consumers' preferences. The relationship between gender and consumer preferences for yam was studied using purposeful sampling for key informants, focus group discussions (FGDs), and individual interviews. Data from qualitative interviews were transcribed and quantitative data analyzed using SPSS (version 20). Cramer's V (Phi) and logistic regressions were used to explain the observations. Males prioritized income generating varieties over females, while females ranked tuber morphological characteristics high. Sex-based preference for yams showed that moldability and sweet taste are preferred by both females and males. Moderately hard boiled yams and shelf stable food products are liked by males, whereas aroma is rated highly by females. Males described yams that have a longer digestion time as “heavy” and preferred such varieties. Watery tubers and tubers not turning brown are important characteristics during processing. The Phi of 0.157 and 0.163 for sex and ethnic groups show moderate to strong associations between choices for descriptors by females, males, and various ethnic groups. These findings imply that gender disaggregation of information on preference for yam quality descriptors should be considered in future yam breeding programs as it may improve adoption rate and enhance food security.
- ItemWatermelon Seeds as Food: Nutrient Composition, Phytochemicals and Antioxidant Activity(International Journal of Nutrition and Food Sciences., 2016) Tabiri, Betty; Agbenorhevi, Jacob K.; Wireko-Manu, Faustina D.; Ompouma, Elsa I.; 0000-0002-8516-7656; 0000-0002-5020-6299Watermelon (Citrullus lanatus) seeds are often discarded while the fruit is eaten. In this study, seeds of three (3) varieties of watermelon (Charleston gray, Crimson sweet and Black diamond) were analyzed for their proximate, minerals, phytochemicals, total phenols content and antioxidant activity. The proximate analysis and phytochemicals screening were performed using standard procedures whereas minerals content was determined by atomic absorption spectrophotometry. DPPH free radical scavenging activity and Folin-ciocalteau assays were used to determine antioxidant activity and total phenol content, respectively. The results indicated that the watermelon seeds had moisture content in the range of 7.40 - 8.50%; fat, 26.50 - 27.83%; protein, 16.33 - 17.75%; fibre, 39.09 - 43.28%; ash, 2.00 - 3.00%; carbohydrate, 9.55 - 15.32% and energy value of 354.05 - 369.11 kcal/100g. The seeds also contained appreciable minerals (Ca, P, Mg, Na, K and Zn) with K (3.40-3.5 mg/100g) being the highest while Na (0.07 - 0.08 mg/100g) was the least. DPPH% inhibition varied between 59.88-94.46% inhibition with trolox equivalent of 82.59-130.29 µM/g depending on the variety. Saponins, tannins, triterpenoids glycosides and alkaloids were present in all samples. Crimson sweet seeds had the highest total phenol content (5416 mgGAE/100g), followed by Black diamond (3949 mg GAE/100g) and the least, Charleston gray (1494 mg GAE/100g). Similarly, Crimson sweet had the highest antioxidant activity, followed by Black diamond and lastly, Charleston gray. The present findings suggest watermelon seeds as considerable source of nutrients in the diet and may have health and economic benefits due to its fibre, minerals, phenolics content and antioxidant activity.
- ItemYam pectin and textural characteristics: a preliminary study(International Journal of Food Properties, 2022) Effah-Manu, Liticia; Maziya-Dixon, Bussie; Wireko-Manu, Faustina D.; Agbenorhevi, Jacob K.; Oduro, Ibok N.; 0000-0003-3731-2684; 0000-0003-2014-2201; 0000-0002-5020-6299; 0000-0002-8516-7656; 0000-0003-3731-2684
- ItemYam Tuber Dormancy and Sprouting: The Role of Concentration Dynamics of Endogenous Gibberellic Acid(Agricultural and Food Science Journal of Ghana., 2021-12) Boateng, M. A.; Amoako-Andoh, F. O.; Wireko-Manu, Faustina D.; Agbenorhevi, Jacob K.; 0000-0002-5020-6299; 0000-0002-8516-7656The role of endogenous gibberellic acid (GA3 ) in the regulation of yam (Dioscorea spp.) tuber dormancy was investigated by determining the changes in the endogenous GA3 levels during natural dormancy progression. Two Dioscorea rotundata cultivars ('Pona' and 'Labreko') and one Dioscorea alata cultivar ('CRI-Ahoɔdenfoɔ') used in these studies have varying dormancy duration. Endogenous GA3 levels determined for the yam tubers ranged from 1.53 – 3.05 mg/g dw and 1.23 – 1.58 mg/g dw for 'Pona'; 1.53 – 3.40 mg/g dw and 1.25–1.57 mg/g dw for 'Labreko'; 1.48 – 3.62 mg/g dw and 1.28 – 1.60 mg/g dw for 'CRI-Ahoɔdenfoɔ', respectively, for the outer and inner portions. 'Pona' and 'Labreko' had dormancy break at 60 days after harvest (DAH), but at 90 DAH for 'CRI-Ahoɔdenfoɔ'. Generally, GA3 levels increased from harvest to the maximum at 30 DAH, then declined to the minimum at 60 DAH before finally increasing again at 90 DAH for the outer portions of the yam tuber. For the inner portions of the tuber, GA3 levels rather declined significantly to the minimum at 30 DAH, increased at 60 DAH and then decreased again at 90 DAH. GA3 levels in the outer portions of the tubers increased by 84-122%, 65-77% and 61- 65%, respectively, in 'CRI-Ahoɔdenfoɔ', 'Labreko' and 'Pona', but decreased in the inner portions by 19-23%, 24-26% and 26-28%. Essentially, higher amounts of endogenous gibberellins in yam tubers induced longer dormancy duration whereas lower amounts were indicative of dormancy termination and subsequent initiation of sprouting.