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(2023) Amankwah, Akosua Mawuse;
Circular economy strategies may appear practical for business but are complex in application. Country-specific situations, taking into consideration the cultural dimensions, aid the practicality of such strategies. As part of a longitudinal research, this study sought to identify and evaluate circular strategies that could be integrated into selected fashion SMEs in Ghana. An in-depth qualitative case study was adopted to engage nineteen owner-designers of SMEs through interviews and observations. The owner-designers must have formal businesses, have been running their retail stores during the last decade and operate within the two major cities in Ghana where population growth supports economic activities. Life extension strategies were adopted for the study. The indications were that the majority of owner-designers of fashion SMEs, although practicing some circular strategies unknowingly, were not motivated to formally integrate the practice into their businesses. Cost, time, labour and consumer attitudes and behaviour were factors considered to undermine the effectiveness of adopting and implementing circular strategies in these firms. Creation of awareness of circular strategies and models for their implementation are needed to enable practitioners to imbibe circular economy principles in fashion SMEs in Ghana.
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.
Rheological and microstructural investigation of oat -glucan isolates varying in molecular weight
(International Journal of Biological Macromolecules, 2011) Agbenorhevi, Jacob K.; Kontogiorgos, Vassilis; Kirby, Andrew R.; Morris, Victor J.; Tosh, Susan M.; 0000-0002-8516-7656
The rheological properties and microstructure of aqueous oat -glucan solutions varying in molecular weight were investigated. The structural features and molecular weights (MW) were characterized by 13C NMR spectroscopy and high performance size-exclusion chromatography (HPSEC), respectively. The microstructure of the -glucans dispersions was also examined by atomic force microscopy (AFM). The samples with -glucan content between 78 and 86% on a dry weight basis had MW, intrinsic viscosity ([ ]) and critical concentration (c*) in the range of 142–2800 × 103 g/mol, 1.7–7.2 dl/g and 0.25–1.10 g/dl, respectively. The flow and viscoelastic behaviour was highly dependent on MW and on the concentration of the -glucans dispersions. Pseudoplastic behaviour was exhibited at high concentrations and Newtonian behaviour was evident at low concentrations. At the same concentration,the viscosity was higher for higher MW samples. The Cox–Merz rule was applicable for the lower molecular weight samples at higher concentrations whereas the high molecular weight sample deviated at concentrations greater than 1.0%, w/v. The mechanical spectra with variation of both MW and concentration were typical of entangled biopolymer solutions. AFM images revealed the formation of clusters or aggregates linked via individual polymer chains scattered heterogeneously throughout the system. The aggregate size increased with the molecular weight of the samples investigated and has been linked to the rheological behaviour of the samples
Quality of Miracle Berry Wine as Influenced by pH and Inoculum Levels
(Journal of Food and Nutrition Research, 2019) Agbenorhevi, Jacob K.; Alemawor, Francis; Engmann, Felix N.; Aduboffour, Stephen K. ; 0000-0002-8516-7656; 0000-0003-0985-8727
Synsepalum dulificum (also known as miracle berry) fruit is rich in nutrients, flavour and antioxidant compounds. However, the fruit is underutilized in the sub region and susceptible to post harvest losses. In this study, miracle berry wine was produced and the effects of varying pH and inocula levels during fermentation (at room temperature for 7 days) on the wine parameters (soluble solids, pH, titratable acidity, acid taste index, total phenols and antioxidant activity) were investigated. During fermentation, changes in ˚brix and pH were also monitored. Total soluble solids varied between 4.8-20°Brix while total phenols and antioxidant activity (% DPPH inhibition) ranged 300-580 mg GAE/L and 52-86 %, respectively. There was a decrease in ˚Brix, pH, phenolic content and antioxidant activity for all samples fermented at varying pH after fermentation. There was, however, an increase in titratable acidity (7-14 g/L tartaric acid) and acid taste index after fermentation. Wine samples produced at pH of 3.8, 4.6 and 5.8 using 1% inoculum produced 13%, 10% and 10% (v/v) alcohol, respectively. With respect to varying inocula, there was a decrease in ˚Brix, pH, phenolic content and antioxidant activity for wine samples produced at pH of 4.6 and inocula of 1% and 2%, respectively, but increased in titratable acidity and acid taste index after fermentation. At the end of the fermentation process, wine sample with pH 4.6 and inocula of 1% and 2% had alcohol content of 10% and 12% (v/v), respectively. The study revealed that it is possible to produce red wine from miracle berry rich in antioxidant with possible health imparting benefits. Again, varying the pH and inoculum levels can affect the quality of the wine produced.
Proximate Composition and Functional Properties of Some New Groundnut Accessions
(Journal of Food Security, 2017) Khalid, Alhassan; Agbenorhevi, Jacob K.; Asibuo, James Y.; Sampson, Gilbert Owiah; 0000-0002-8516-7656; 0000-0002-5960-9529; 0000-0002-2175-4683
Ten new accessions of groundnut (Arachis hypogea) were oven dried and processed into full fat powdered forms and analysed for the proximate and functional properties using AOAC official methods. The crude protein ranged 20.7-25.3%, crude fat 31- 46%, ash 1.2-2.3%, crude fiber 1.4 -3.9%, carbohydrate 21-37% and moisture 4.9-6.8 %. Energy values of the groundnut accessions were between 525 kcal/100g and 606 kcal/100g. The ash, moisture, carbohydrate, fat and fiber values of all groundnut accessions proved to be significantly different whereas there was no significant difference amongst the protein values at p ≤ 0.05. The bulk density ranged between 0.63 g/cm3 and 0.88 g/cm3 whereas water absorption capacities were between 20 % and 30 %. Swelling power ranged from 2.98 g/g to 4.18g/g and solubility index was between 26.5% and 57% with no significant difference at p ≤ 0.05. Foaming capacity ranged from 4.0-16.2 % and stability 94-100%. Samples showed a significant difference in terms of bulk density at p ≤ 0.05. The relatively high protein content of all the accessions as well as their functional properties make them a valuable protein supplement in weaning foods as well as the treatment of protein energy malnutrition cases.
Pasting properties of starch-okra pectin mixed system
(CyTA - Journal of Food, 2020) Bawa, Nadratu Musah; Agbenorhevi, Jacob K.; Kpodo, Fidelis M.; Sampson, Gilbert Owiah; 0000-0002-8516-7656
The pasting properties of starch are influenced by the starch-hydrocolloid interaction in the mixed system. In this study, the effect of pectin extract from three okra genotypes (Agbagoma, Asontem, and Sengavi) at concentrations of 0%, 5%, 10%, and 15% on the pasting properties of starch were investigated. The pasting properties of the mixed systems were determined using the Rapid ViscoAnalyzer. The results showed that okra pectin decreased the peak viscosity and setback value of starch with the highest exhibited by Agbagoma and Asontem. The final viscosity of starch was increased in most samples except for 10–15% Agbagoma and 15% Asontem pectin systems. The peak time (3.84 − 6.84 min) increased with increasing okra pectin concentration. Pasting temperature for the mixed systems ranged from 51.24 o C (for 10% Sengavi) to 80.65°C (for 15% Agbagoma). Overall, okra pectin affected the pasting properties of starch and decreased starch retrogradation.
Packaging 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; 0000-0002-5020-6299
Maize-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.