Browsing by Author "Oduro, Ibok N."

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    Antioxidant 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; 0000-0003-3731-2684
    The 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.
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    Characterization of Starch from New Cassava Accessions at Different Maturity
    (Journal of Food Security, 2019) Williams, G.; Ansah, K. O.; Agbenorhevi, Jacob K.; Oduro, Ibok N.; Bobobee, E.; 0000-0002-8516-7656; 0000-0003-3731-2684; 0000-0002-1949-9396
    Cassava (Manihot esculanta) is a root crop which serves as an important source of starch on a global scale. The objective of this work was to investigate the characteristics of starch from some new cassava accessions at different maturity. Six new cassava accessions (Abrabopa, Agra, Amansen, Ampong, Bankyehemma and Duadekpakpa) were harvested at four different months (from April – July 2017; i.e., 7-10th month) after planting. The starch was extracted using the conventional method of starch extraction and their yield calculated. The amylose was determined by means of spectrophotometry whereas pasting properties of the starches were analyzed using Rapid Visco Analyzer. Average starch yield ranged from 18-29% with the highest yield recorded in the 10th month for the various varieties studied. There were no significant differences (p > 0.05) in the peak viscosity, final viscosity, peak time and pasting temperature but significant differences were recorded for setback, trough and breakdown of the starch samples. The amylose (14-25%) and amylopectin (76-85%) content of the varieties differed significantly (p < 0.05). The present work shows that maturity affects the starch yield, composition and pasting properties of the new cassava accessions and this should be considered in deciding the time to harvest each accession for specific food and non-food industrial applications.
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    Chemical, 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
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    Development 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; 0000-0003-3731-2684
    Most 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
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    Development 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; 0000-0003-3731-2684
    Most 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.
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    Dietary 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; 0000-0003-3731-2684
    The 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 .......................................
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    Diversity and domestication of mushroom species in the Atewa forest reserve and Bia Biosphere, Ghana
    (Scientific African, 2023) Dzomeku, Matilda; Alemawor, Francis; Agbenorhevi, Jacob K.; Oduro, Ibok N.; Obodai, Mary; 0000-0002-6527-6978; 0000-0003-0985-8727; 0000-0002-8516-7656; 0000-0003-3731-2684; 0000-0003-0776-6095
    Edible mushrooms commonly found in forest reserves are important for food security but they are underutilized in Ghana. The Atewa forest reserve in the Eastern Region and Bia Biosphere in the Western Region are among the largest forest reserves in Ghana. However, human activities including illegal mining activities pose a threat to the existence of the rich mushroom diversity within these forests. The objective of this study, therefore, was to collect, characterize and domesticate mushrooms from the Atewa forest reserve and the Bia Biosphere. Wild mushroom samples were randomly photographed, collected, dried and stored. Edible and wild mushrooms were characterized morphologically and compared with literature. A total of 86 mushroom samples (comprising 45 from the Atewa forest reserve and 41 from the Bia Biosphere) were collected and identified. The two forest reserves contained a rich diversity of wild mushrooms namely: Cookeina speciosa, Marasmiellua inoderma, Auricularia cornea, Daldina concentrica, Pleu rotus sp. Polypores. Cultivated Auricularia auricula strain AUAT recorded the highest ash content (16.70%) while cultivated Ganoderma sp. strain GLB recorded the lowest ash content (5.12%). On the other hand, cultivated Pleurotus ostreatus strain POB recorded the highest fat content of 19.88% and cultivated Pleurotus saju-caju strain PSCAT gave the least value of 12.02%. Cultivated Auricularia auricula strain AUAT again recorded the highest protein value of 33.38% while wild Ganoderma sp. Strain GLB had the least protein value. A total carbohydrate level of 64.22% was observed in cultivated Ganderma sp. strain GLB. The highest oxalate content of 30.93 mg/100 g was recorded in cultivated Pleurotus ostreatus strain EM1 with cultivated Auricularia auricula strain AUAT being the least value of 4.73 mg. A high phytate value of 149.35 mg was observed in cultivated Auricularia auricula strain AUAT and cultivated Pleurotus saju-caju strain PLAT showed the lowest value of 31.60 mg/100 g. The present findings provide considerable data on fungal diversification, conservation and domestication as well as a reference point for future studies.
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    Effect of Processing Methods on the Proximate Composition, Total Phenols and Antioxidant Properties of Two Mushroom Varieties
    (American Journal of Food and Nutrition, 2018) Asamoa, Abena A.; Essel, Esther A.; Agbenorhevi, Jacob K.; Oduro, Ibok N.; 0000-0002-8516-7656; 0000-0003-3731-2684
    Mushrooms are traditionally consumed as food and are known to possess nutritional and medicinal properties. However, the choice of processing methods for mushrooms are often based on preference rather than the impact on nutritional or health benefits. The effect of solar drying, steaming and roasting on the proximate, phytochemicals and antioxidant activity of two mushroom varieties (Termitomyces schimperi and Volvariella volvacea) were investigated. Proximate analysis and phytochemical screening were carried out using standard protocols. The total phenols content and antioxidant activity were determined by means of Folin-Ciocalteu method and 1, 1-Diphenyl-2-picryl-hydrazyl (DPPH) assay, respectively. Results indicate that both processing methods and varietal differences had effects on nutrient composition of mushrooms. Solar drying retained most nutrients in both varieties. Dried T. schimperi had the highest protein content of 29.09 % whereas dried V. volvacea had the highest carbohydrate and ash contents of 60.71% and 5.56 %, respectively. Steamed mushrooms retained moisture and had the lowest carbohydrate content with steamed V. volvacea having the highest moisture and lowest carbohydrate values of 91.15% and 54.71%, respectively. Roasting also showed a high protein content of 28.65% in T. schimperi and a high carbohydrate of 58.65% in V. volvacea. None of the processing methods however had a significant effect on fat and fibre contents of both varieties used. The phytochemicals tested were present in both varieties in the processed and unprocessed forms. The steamed extract was the strongest scavenger of DPPH with 50 % inhibitory concentration (IC50) value of 3.03 ± 0.40 mg/mL whereas the unprocessed extract had the least effect with IC50 value of 9.35 ± 0.42 mg/ml. Similarly, the steamed extract recorded the highest total phenol content with value of 1644 ± 39 mg GAE/100 g whereas the unprocessed extract was the lowest with value of 1336 ± 93 mg GAE/100 g respectively. The present findings suggest that steamed mushrooms possess the highest antioxidant acti
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    Effect of soaking, autoclaving and repeated boiling on oligosaccharides in cowpea.
    (Nigerian Food Journal, 2007) Agbenorhevi, Jacob K.; Oduro, Ibok N.; Ellis, William Otoo; Abodakpi, V. D.; Eleblu, S. E.; 0000-0002-8516-7656; 0000-0003-3731-2684
    Oligosaccharidesin beans are known to be the major cause of flatulence associated with beans consumption. The effects of soaking, autoclaving and repeated boiling on the oligosaccharide levels in ten cowpea varieties were studied. The oligosaccharides were extracted in 70% aqueous ethanol and separated by thin layer chromatography(TLC) method. The quantitation was done using the spectrophotometer. The results showed that the total oligosaccharide content varies among the cowpea varieties; 0.197 - 0.918g/100g. IT93K-596 had the lowest oligosaccharide content (0.197g/100g) and IT94K-410-2 the highest (0.918g/100g). Autoclaving, soaking and repeated boiling had a reductive effect on the total oligosaccharides content in the cowpeas used.Autoclaving reduced raffinose level by 23-68%,stachyose level by 12-81% and total oligosaccharides level by 23- 74%. Repeated boiling reduced the raffinose level by 23-61%; stachyose, 20-58% and total oligosaccharide by 15-55%. The loss of raffinose and stachyose after soaking ranged from 18.2-53.6% and 20.4-75.1% respectively and the total oligosaccharide loss, 25.1-63.9%. These treatments are therefore recommended for oligosaccharide reduction in cowpeas however their efficiency is variety dependent. These processing methods promise improved utilization or consumption of cowpea in the sense of curbing flatulence associated with beans meal.
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    Effect of soaking, autoclaving and repeated boiling on oligosaccharides in cowpea.
    (Nigerian Food Journal, 2007) Agbenorhevi, Jacob K.; Oduro, Ibok N.; Ellis, William Otoo; Abodakpi, V. D.; Eleblu, S.E.; 0000-0002-8516-7656; 0000-0003-3731-2684; 0000-0001-6993-4731
    Oligosaccharides in beans are known to be the major cause of flatulence associated with beans consumption. The effects of soaking, autoclaving and repeated boiling on the oligosaccharide levels in ten cowpea varieties were studied. The oligosaccharides were extracted in 70% aqueous ethanol and separated by thin layer chromatography(TLC) method. The quantitation was done using the spectrophotometer. The results showed that, the total oligosaccharide content varies among the cowpea varieties; 0.197 - 0.918g/100g. IT93K-596 had the lowest oligosaccharide content (0.197g/100g) and IT94K-410-2 the highest (0.918g/100g). Autoclaving, soaking and repeated boiling had a reductive effect on the total oligosaccharides content in the cowpeas used. Autoclaving reduced raffinose level by 23-68%,stachyose level by 12-81% and total oligosaccharides level by 23-74%. Repeated boiling reduced the raffinose level by 23-61%; stachyose, 20-58% and total oligosaccharide by 15-55%. The loss of raffinose and stachyose after soaking ranged from 18.2-53.6% and 20.4-75.1% respectively and the total oligosaccharide loss, 25.1-63.9%. These treatments are therefore recommended for oligosaccharide reduction in cowpeas however their efficiency is variety dependent. These processing methods promise improved utilization or consumption of cowpea in the sense of curbing flatulence associated with beans meal.
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    Gender-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; 0000-0003-3731-2684
    Gender-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.
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    Improved 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; 0000-0003-3731-2684
    This 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.
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    Improved Yam-Baobab-Tamarind flour blends: Its potential use in extrusion cooking
    (Scientific African, 2019) Adams, Zeenatu Suglo; Manu, Faustina Dufie Wireko; Agbenorhevi, Jacob K.; Oduro, Ibok N.; 0000-0001-9763-4023; 0000-0002-5020-6299; 0000-0002-8516-7656; 0000-0003-3731-2684
    This project was aimed at determining the physicochemical properties of water yambaobab-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 preferred 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.
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    Okra pectin as lecithin substitute in chocolate
    (Scientific African, 2019) Datsomor, Delight N.; Agbenorhevi, Jacob K.; Kpodo, Fidelis M.; Oduro, Ibok N.; 0009-0002-2835-8015; 0000-0002-8516-7656; 0000-0002-7949-0502; 0000-0003-3731-2684
    The effect of okra (Abelmoschus spp.) pectin as an emulsifier on the yield, textural properties, sensory and consumer acceptability of different chocolate formulations was investigated. Pectin was isolated from okra pods and incorporated into milk chocolate as lecithin substitute (emulsifier) at different levels (10–100%). Texture profile analysis and sensory evaluation (5-point hedonic scale) was performed on the different chocolate formulations. It was found that with increasing pectin content viscosity of the mixed system increased during milling and conching, which resulted in slower flow rate during draining from the ball mill and decreased yield. Substitution at 25:0 (%) (pectin: lecithin) yielded 84 bars of 9 g of chocolate per 1500 g of formulation after draining for 30 min compared to formulations containing lecithin. Chocolate samples 25:75 (%) (pectin:lecithin) had the highest overall acceptability (4.37 ± 0.30) which was not significantly different (p> 0.05) from sample 25:0 with overall acceptability of 4.23 ± 0.30. All the chocolate samples from the various formulations studied had similar sensory properties as well as textural parameters (hardness, cohesiveness, adhesiveness, springiness and chewiness). The present findings suggest that it is possible to use okra pectin as emulsifier to produce milk chocolate which is acceptable to consumers
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    Pectin isolation and characterization from six okra genotypes
    (Food Hydrocolloids, 2017) Kpodo, Fidelis M.; Agbenorhevi, Jacob K.; Alba, K.; Bingham, , R. J.; Oduro, Ibok N.; Morris, G. A.; Kontogiorgos, V.; 0000-0002-7949-0502; 0000-0002-8516-7656
    Pectin was isolated by aqueous extraction at pH 6.0 from the pods of six different okra genotypes (Abelmoschus esculentus L.). Genetic diversity was determined using fragment length analysis (FLA) of ten simple sequence repeat (SSR) markers. Physical and chemical evaluation of pectin was performed by means of FT-IR and NMR spectroscopy, sugar composition analysis (GC-MS), size exclusion chromatography coupled to multi-angle laser light scattering (SEC-MALLS), dilute solution viscometry and steady shear rheology assisted by principal component analysis (PCA). Each of the SSR markers detected on average 4.1 alleles and revealed unique genotypes for each sample. Extraction yield was between 11 and 14% resulting in pectin with galacturonic acid content between 43 and 63%, low degree of methyl-esterification (17–25%) and high degree of acetylation (20–40%). All samples were of high weight-average molar mass (Mw) (700–1700 × 103 g mol−1) and sugar composition analysis revealed the structural diversity of samples with HG/RG-I ratios ranging between 1.3 and 3.1. The present work shows that individual okra genotypes provide pectin with different structural properties that could potentially provide a new source of functional pectin for the food or pharmaceutical industries.
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    Pectin isolation and characterization from six okra genotypes
    (Food Hydrocolloids, 2017) Kpodo, Fidelis M.; Agbenorhevi, Jacob K.; Alba, K.; Bingham, R. J.; Oduro, Ibok N.; Morris, G. A.; Kontogiorgos, V.; 0000-0002-7949-0502; 0000-0002-8516-7656; 0000-0003-3731-2684
    Pectin was isolated by aqueous extraction at pH 6.0 from the pods of six different okra genotypes (Abelmoschus esculentus L.). Genetic diversity was determined using fragment length analysis (FLA) of ten simple sequence repeat (SSR) markers. Physical and chemical evaluation of pectin was performed by means of FT-IR and NMR spectroscopy, sugar composition analysis (GC-MS), size exclusion chromatography coupled to multi-angle laser light scattering (SEC-MALLS), dilute solution viscometry and steady shear rheology assisted by principal component analysis (PCA). Each of the SSR markers detected on average 4.1 alleles and revealed unique genotypes for each sample. Extraction yield was between 11 and 14% resulting in pectin with galacturonic acid content between 43 and 63%, low degree of methylesterification (17e25%) and high degree of acetylation (20e40%). All samples were of high weightaverage molar mass (Mw) (700e1700 103 g mol1 ) and sugar composition analysis revealed the structural diversity of samples with HG/RG-I ratios ranging between 1.3 and 3.1. The present work shows that individual okra genotypes provide pectin with different structural properties that could potentially provide a new source of functional pectin for the food or pharmaceutical industries.
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    Physicochemical and pasting properties of flour and starch from two new cassava accessions
    (International Journal of Food Properties, 2023) Aidoo, Raphael; Oduro, Ibok N.; Agbenorhevi, Jacob K.; Ellis, William O.; Pepra-Ameyaw, Nana` B.; 0000-0002-2891-5128; 0000-0003-3731-2684; 0000-0002-8516-7656; 0000-0001-6993-4731; 0000-0003-4904-4947
    Some new cassava accessions have been developed and released because of their high yield, resistance to disease, adaptability to wider ecological environment, and less cost of production. However, their flour and starch properties have not been characterized for potential food applications. In the present study, starch and flour were produced from two new cassava accessions (Sika Bankye and Bankye Hemaa) and evaluated for their physicochemical and pasting properties. The flour samples recorded higher values for the various functional parameters compared to their starch counterparts. Both flour samples had a similar water absorption capacity (WAC) of ~263% but the associated starch from Bankye Hemaa recorded the lowest value of 38.6%. Bankye Hemaa flour recorded the highest oil absorption capacity (OAC) (121%) and could be exploited as potential flavor retainer in products. Flour from Bankye Hemaa also recorded the highest swelling power (882 ± 29%), which was indicative of their good thickening and stabilizing functionalities. Sika Bankye starch had the highest setback viscosity (723 ± 32 RVU), which was indicative of its lower susceptibility to retrogradation and potential use in products that require highly viscous paste and processed at high temperatures.
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    Physicochemical variability of pectin from different okra phenotype
    (Journal of Ghana Science Association, 2021-10-24) Kpodo, Fidelis M.; Agbenorhevi, Jacob K.; Oduro, Ibok N.; Morris, G. A.; 0000-0002-7949-0502; 0000-0002-8516-7656; 0000-0003-3731-2684
    Okra (Abelmoschus esculentus L.) is a readily available plant in Ghana and considered an abundant source of pectic polysaccharides which are useful ingredients for the functional food industry. Pectin extracts from eight different okra samples obtained from different sources were evaluated for their physicochemical and functional properties. The structural and molecular characteristics were analysed by means of Fourier transform infra-red (FTIR) spectroscopy, nuclear magnetic resonance spectroscopy (NMR) and size-exclusion coupled to multi-angle light scattering (SEC-MALS). The water absorption, oil absorption and emulsification capacities of the pectin extracts were determined. Results showed that the crude okra pectins had total carbohydrate contents in the range of 59.2 to 70.2% whereas protein content varied from 8.0 to 15.1%. The FTIR and 1H-NMR spectra revealed similar structural features whereas the weight average molecular weight (Mw) ranged widely from 320×103 to 7600×103 gmol–1 in the order Pora < Akrofo < Asha < Asontem < Penkrumah (Techiman) < Sengavi < Penkruma (Kenkeso) < Agbagoma.The water/oil absorption capacity and emulsification capacity of the pectin isolates also varied depending on the geographical source. The relatively high galacturonic acid content of the pectins conferred hydrophilic characteristics that positively influenced the water absorption capacity of the polymers in solution. Pectin from the okra phenotypes Sengavi and Agbagoma shown to have low RG-I fractions demonstrated increased oil holding (378g/100g and 384g/100g respectively) and emulsification capacities (45%). The present findings indicate that the differences in pectin characteristics among the okra phenotypes have the potential to be exploited for different technological applications.
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    Quality Characteristics of Native Starch fr om Selected Improved V arieties of Sweetpotato (Ipomoea batatas)
    (Agricultural and Food Science Journal of Ghana, 2017-08) Adu-Kwarteng, E.; Oduro, Ibok N.; Ellis, William O.; Agbenorhevi, Jacob K.; 0000-0003-3731-2684; 0000-0001-6993-4731; 0000-0002-8516-7656
    Sweetpotato (Ipomoea batatas L.) is a starchy root crop with a wide range of diversity in physical and compositional characteristics. Links between starch properties and processing characteristics are known to have an impact in utilization. Starches were extracted from six (6) improved varieties of sweetpotato harvested at 3, 4 and 5 months after planting. Starch granule morphologies were characterized at 4 months using Light Microscopy, and starch pasting properties were determined at all harvest times by Rapid Visco Analyzer. Granular shapes were generally heterogeneous and approximate size distributions varied from 2 to 15m to 8 to 40m. peak viscosity ranged from 4077 to 5260 centipoise, pasting temperature ranged from 77.95 to 82.45oC, setback ratio ranged from 1.25 to 1.61 and stability ratio ranged from 0.52 to 0.73. Starches with smaller granules had relatively low peak viscosities and high stability or resistance to breakdown while those with larger granule size ranges had lower setback ratio, indicating less retrogradation and better long-term cold paste stability. The influence of both variety and harvest maturity on all RVA pasting properties were significant at p< 0.001. Small starch granule size varieties harvested at 4 and 5 months had the lowest peak viscosities and highest setback ratio; larger granule size varieties harvested at 4 months had the highest peak viscosities and lowest setback ratio. These results are relevant in understanding the processing and utilization quality of the varieties studied, and also in identifying potential niche applications for sweetpotato starch as food ingredients or in other applications
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    Structure-Function Relationships in Pectin Emulsification
    (Food Biophysics, 2018) Kpodo, Fidelis M.; Agbenorhevi, Jacob K.; Alba, K.; Oduro, Ibok N.; Morris, G. A.; Kontogiorgos, Vassilis; 0000-0002-7949-0502; 0000-0002-8516-7656; 0000-0003-3731-2684
    The emulsifying characteristics of pectins isolated from six different okra genotypes were investigated and their structurefunction relationships have been evaluated. Emulsion formation and stabilization of acidic oil-in-water emulsions (pH 2.0, φ = 0.1) were studied by means of droplet size distribution, ζ-potential measurements, viscometry, interfacial composition analysis and fluorescence microscopy. Fresh and aged emulsions differed in terms of droplet size distribution, interfacial protein and pectin concentrations (Γ) depending on the molecular properties of pectin that was used. Specifically, pectins with intermediate length of RG-I branching with molar ratio of (Ara + Gal)/Rha between 2 and 3 exhibit the optimum emulsification capacity whereas samples with the molar ratio outside this range do not favour emulsification. Additionally, low amounts of RG-I segments (HG/RG-I > 2) improve long term stability of emulsions as opposed to the samples that contain high amounts of RG-I (HG/RG-I < 2) which lead to long term instability. Protein was not found to be the controlling factor for the stability of the dispersions. The present results show that rational design of pectin should be sought before application as functional ingredient in food and/or pharmaceutical systems.