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Item Predictors Of Potentially High Risk For Preeclampsia Among Pregnant Women Attending Antenatal Clinics At Selected Hospitals In Accra(University Of Ghana, 2021-07) Abban, H.A.Introduction: Preeclampsia/Toxemia (PE) is a genuine hypertension condition related with maternal and infant ill health and death during pregnancy. Preeclamptics as well as their babies/children develop health conditions including cardiovascular disease as well as growth conditions well along in life. In Ghana, prevalence of PE has been known to be as low as 2.5% in Ghana Police hospital and as high as 48.8% in Komfo Anokye Teaching Hospital. Most of the studies carried out on PE has been case control and hence do not have enough data on the possible exposures at the early stages of pregnancy which may have led to the developing of PE. Also only a few studies has been carried out on the predictors associated with preeclampsia. Objective: This current prospective cohort study sought to determine the factors at the various stages of pregnancy; ≤ 20 weeks gestation through 28 –32 weeks and during 6 weeks postpartum which may predispose the pregnant women to a potentially high risk for PE. Methodology: This was prospective cohort study involving 403 pregnant women who were recruited at ≤ 20 weeks gestation. Nonetheless, 21 participants dropped out between weeks 28 and 32, and 24 participants also dropped out at 6 weeks postpartum leaving 358 participants in the study. The study took place at the Ghana Police Hospital, Cantonment, and the University of Ghana Hospital, Legon, both in Accra. The entire study lasted for 21 months (May, 2018 – Feb.2020). Structured questionnaires that had been pre-tested were used to obtain information on the participants' backgrounds, lifestyle practices, gynecological factors, dietary factors, stress status, BMI, biochemical data (haemoglobin, proteinuria), clinical data (blood pressure), family history of chronic conditions, morbidities among other factors. The criteria used for potentially high risk for preeclampsia was having at least a systolic blood pressure of ≥130 mmHg or diastolic blood pressure of ≥80 mmHg or oedema or proteiunuria. Background categorical variables were computed as frequencies and percentages, whereas continuous variables were enumerated as median (interquartile range; Q1, Q3) or means ± SD, as appropriate. The predictors of possibly high risk for PE were investigated using binary logistic regression and finally path analysis was run to determine the path way through which the predictors operate. Results: The age on average of expectant mothers is 31 ± 5 years, a greater number 194 (48%) of expectant mothers had attained tertiary education, median gestational age at first time ante natal booking was 14 (12, 17) weeks, Akan ethnicity was dominating 166 (41.0%) and 347 (86.0%) of the women were married. Prevalence of serum vitamin D and calcium deficiencies were 48.3% and 53.2% respectively with 34.0% being at a potentially high risk for PE. Predictors of potentially high risk for PE were the following; estimated pre – pregnancy body mass index (≥ 30 kg/m2) AOR = 3.6 (95% CI = 1.01 – 11.750) p value 0.040 and estimated pre- pregnancy weight (> 71 kg) AOR = 3.4 (95% CI = 1.250 - 12.703) p 0.019. From path analysis, path relationship for anthropometric indices (estimated pre – pregnancy BMI and estimated pre- pregnancy weight) and potentially high risk for preeclampsia shows a favorable and significant direct association (β = 0.519; t-value = 8.545; p-value = 0.001). Conclusion: Predictors of potentially high risk for PE among the participants were estimated pre-pregnancy BMI and estimated pre-pregnancy weight (weight measured at the first antenatal clinic). In contrast to findings of most studies, serum vitamin D and calcium deficiencies had no association with PE.Item Physicochemical, Functional Properties And Mycotoxin Occurrence Of Ghanaian Tigernuts (Cyperus Esculentus L.)(University of Ghana, 2020-11) Battuta-Dawlah, S.T.ABSTRACT In Ghana, tigernut (Cyperus esculentus L.) is grossly underutilized in food applications and is mostly consumed raw as a snack. However, the soil and climate conditions of the country are conducive for cultivation of the crop on a large scale for applications in food for local consumption, industrialisation and for the export market. Food applications of tigernut and its derivatives and their possible inclusion as ingredient in the Ghanaian diet would require knowledge on its handling quality and functional properties. The aim of this study was to characterise Ghanaian tigernut as an ingredient for possible food applications. The study design consisted of two parts: (a) a cross-sectional survey of different categories of stakeholders using pre-tested semi-structured questionnaires (b) followed by laboratory designed experiments to study the quality, physicochemical and functional properties of tigernut as a function of tigernut variety and process conditions. For the surveys, a total of 1277 stakeholders in the value chain, comprising of 711 consumers and 487 traders (wholesalers/retailers) in Greater Accra region and 79 tigernut farmers in the Western and Eastern regions of Ghana, were interviewed using semi-structured researcher-administered questionnaires. The questionnaires sought to gain information on respondents’ level of knowledge on mycotoxins, as well as ascertain if measures were in place to mitigate the risk of fungal colonisation of the crop along the supply chain. Additionally, tigernuts collected at various points along the supply chain (farm, wholesale and retail) were analysed for their mycotoxin (aflatoxins and ochratoxin A) levels using reverse phase High-Performance Liquid Chromatography (HPLC), to determine the hot spots of mycotoxin contamination along the value chain. The second part of the study investigated the physical characteristics of tigernut tubers as well as the functional properties of tigernut flour with the aim of determining its suitability in food applications. Additionally, the shelf life of the tigernut flour was determined by accelerated shelf life testing using the Arrhenius model. Fresh tigernut milk is usually characterised by the sedimentation of starch which influences its flow behaviour as well as the physical stability. Furthermore, heat treatment of the milk leads to gelatinisation of the starches, which also affects the same properties. Consequently, the effects of heat (by roasting tigernuts) and adding α- amylase to the tigernut milk on the physicochemical and functional properties of tiger nut milk were studied. Tigernut oil was extracted and the phenolic and functional properties were determined as well as the effect of heat on these properties. The macro nutritional composition of tigernut tuber, flour, oil and milk were also investigated. The results of the surveys showed that tigernut farmers and consumers had appreciable knowledge in and displayed better attitude towards the prevention of mycotoxin contamination than the tigernut traders (wholesalers/retailers). The educational level of all stakeholders influenced their attitude and knowledge towards the prevention of mycotoxin contamination. Almost all consumers were willing to try new tigernut products such as the flour, oil and milk and would like to see more of these products on the Ghanaian market. The number of samples and the levels of mycotoxins (Ochratoxin A and aflatoxins) increased as the value chain progressed, with retail samples containing all the mycotoxins analysed. Total mycotoxins ranged from 0-27 μg/kg at the farm stage to 0-52 μg/kg at the wholesale stage and finally to 7.9 to 1115.48 μg/kg at the retail stage. These highlight post-harvest stage of the value chain as the focal point for mycotoxin prevention programs, although mycotoxin prevention can be agreed as a cumulative process. Both black and yellowish-brown tigernut flours contained relatively high and comparable amounts of sucrose, glucose and fructose. The relatively high resistant starch content of the tigernut flour makes the flour ideal for diabetics and weight watchers. The yellowish-brown variety had higher total starch content, higher water-retaining ability and viscosity at heating and holding cycles as compared to the black variety. Titratable acidity was found to be the crucial determinant of spoilage in tigernut flour and higher temperature was observed to increase the oxidation of the tigernut flour. This may imply that tigernut flour should be stored below room temperature. Heat and the addition of α- amylase increased the total solids, brix and titratable acidity but caused a decrease in the pH of the tigernut milk. Addition of 0.2% of α- amylase to roasted tigernut milk improved its emulsion stability. Heat and addition of α- amylase caused the tigernut milk to become darker in colour. The flow behaviour of the tigernut milk exhibited shear thinning (pseudoplastic) fluid properties. This implies that commercial production of milk from tigernut must control parameters such as speed of machines during processing as well as concentrations of food additives such as α-amylase. Chemical qualities such as iodine value, peroxide value, ester value, saponification value, free fatty acids and acid value of oil extracted from tigernut tubers, all increased at higher temperatures whilst antioxidant activity and phenolic content decreased. The functional properties of tigernut oil suggested that the oil is good for frying at lower temperatures and for shorter periods. The carbohydrate component of the tigernut tuber was mainly made up of starch and dietary fibre (resistant starches) which reduced in the milk and oil. Crude fat was the second most abundant component in the tigernut tuber. Quercetin and gallic acid were found in appreciable amounts in the tigernut oil. Although, the protein content in the tigernut milk was lower compared to the tuber, it was probably enough to impart desirable functionality to help stabilize the tigernut milk. Tigernut tuber and its derivatives can offer various options in food products. The safety of the tuber and its products can however be improved when stakeholders of the supply chain are educated and supported to implement strategies that prevent mycotoxin contamination.Item Characterisation And Food Applications Of Frafra Potato (Solenostemon Rotundifolius) Flour(University Of Ghana, 2022-07) Tutu, C.O.Frafra potato (Solenostemon rotundifolius) is an underutilised climate-resilient tuber crop commonly cultivated in the tropics, including Ghana. Several accessions of Frafra potato have been identified and bred to broaden its application in different food products. This study characterised the starch and flour made from ten (10) Frafra potato (FP) accessions, from Ghana (released) and Burkina Faso (unreleased), in terms of their starch (FPS) and flour (FPF) yield, and their physicochemical and functional characteristics. FPS yields were similar (p < 0.05) and ranged from 35 to 39% dry matter. FPS also had similar (p < 0.05) colour but differed in paste clarity, ranging from 51 to 63% of the FPS gels. The starches from all accessions displayed similar (p < 0.05) amylose/amylopectin ratio, syneresis %, granule types and shapes. Differences were observed in the thermal properties of the starches, even though XRF and FTIR spectra revealed them to be A-type starches, which is typical of root crops. The variations in granule size and thermal properties between FPS likely affect FP's cooking and eating quality. The released accessions had significantly higher (p < 0.05) protein and ash, ranging from 5.1 to 8.7% and 5.1 to 6.5%, respectively, relative to the unreleased accessions. Four proteins commonly found in tuber crops (lipoxygenase, patatin, sporamin and tarin) and protease inhibitors (Bowman-Birk PIs) were identified in FPF based on their molecular weight (SDS-PAGE). Amino acids analyses (LC/MS) of the FPF identified seven (7) essential amino acids (Valine, Tryptophan, Threonine, Histidine, Methionine, Lysine, and Isoleucine). FPF showed similar functional properties, and their slurries exhibited typical shear-thinning pseudoplastic flow. Particle size analyses of FPF showed them to be generally fine particles, mostly passing through sieve size 100μm, and their sorption behaviour was characterised by a maximum allowable 10% EMC at about 0.5 aw. Considering their fine particle size distribution, relatively high protein content and other functional properties, FPF was used as a replacement for wheat flour in the processing of gluten-free bread. The results showed that the application of dough conditioners (egg-gelatin powder combination) followed by Transglutaminase treatment could technologically be used to develop gluten-free bread from FPFwith comparable attributes as that obtained from wheat flour (WTB). The dough and bread structure showed that the dough conditioners technologically mimicked the gluten-like network, as demonstrated by textural and dough properties. SEM revealed the improved network matrix and well-embedded starch granules in FPB comparable to WTB. A panel of nine (9) trained assessors were used to assess six (6) bread samples, five of which were gluten-free, and one was typical wheat bread, using the Quantitative Descriptive Analysis (QDA®) method. The products were differentiated in appearance by brown crust (top and bottom), smooth bottom crust and homogeneous bottom crust and by a minor bitter flavour note perceived in the gluten-free products. The top and bottom crusts of WTB and B14 had the lowest intensity (lightest) of brown colour in the sample set, but they differed statistically (p ≤ 0.05) from each other. All the bread samples smelled and tasted like typical wheat bread. Sensory profile of the products correlated strongly with the colour and dough properties of FPF. Thus, in developing bread from FPF, attributes of colour and dough properties should be considered. The study showed that FPF has characteristics that make it suitable for gluten-free bakery applications and can help address nutrition and food security in Ghana and Sub-Sahara Africa by promoting its utilisation.Item Microbial Diversity Of Economically Important Unprocessed Freshwater Fishes Sold At The Medina Coura Market In Bamako, Mali(University Of Ghana, 2020-10) Sissoko, A.Around the world, millions of people depend on fish for its high protein content, supply of micronutrients and added health benefits. Fish is extremely perishable; its quality changes very quickly after capture unless it is kept cold. Failure to comply with good preservation practices favors the risk of deterioration in market quality and safety, which may lead to foodborne illness. The purpose of this study was to determine the microbial diversity of fresh water fish and evaluate the food safety knowledge and practices of stakeholders of freshwater fish along selected fish value chains in Mali. A structured face-to-face questionnaire on food safety knowledge and practices was designed and administered to 247 respondents comprising 130 fish sellers and 117 fishermen between November 2018 and February 2019. Samples of three fresh water fish species (Lates niloticus, Clarias anguillaris and Oreochromis niloticus) were taken during cold and hot seasons in four fish production areas and at specific points (capture, landing and selling points) in the selected value chains (Niger Central Delta in Mopti, Selingue, Manantali, Markala) and from the Central fish market (Medina Coura market) using standard protocols for microbial analysis.Water samples at capture areas and swabs of fish containers at each of the landing points were also collected for analysis. The following assessments were carried out: enumeration for Aerobic Plate Count (APCs), Total Coliform counts (TCs), Fecal Coliform counts (FCs), and Spores of Sulphite Reducing Bacteria (SRB), Staphylococcus aureus and prevalence of Salmonella spp. were also determined. Bacterial isolates were identified using biochemical tests (catalase oxidase, API 20E and 20NE). Parasitic infestations of 120 specimens of three freshwater fish species, comprising Lates niloticus (44), Clarias anguillaris (40) and Oreochromis niloticus (36) sold at the Medina Coura market in Mali, were also investigated. The results of the questionnaire survey indicated that respondents had a good level of food safety knowledge but poor food hygiene practices. Most of the respondents had received no formal education in food safety. It is, therefore, important to put in place a good public health management strategy for food sales services, which will give stakeholders in the fish value chain the knowledge and skills necessary to provide hygienic and safe sales services. Microbial growth was observed in all of the fish species tested. APC ranged from 5.08 to 7.64 Log10 CFU.g-1, TC ranged from 4.11 to 7.62 Log10 CFU.g-1, FC ranged from 3.64 to 7.5 Log10 CFU.g-1 and all had 100% higher counts than the national standard. About 12.7% (17/134) of the samples recorded Sulphite Reducing Bacteria, 20.1% (27/134) had Staphylococcus aureus, and 93.3 % (125/134) Salmonella spp.. Three species of parasites were detected, namely, Salmincola edwardsii (crustacea) at the gills, and Philonema sp. and Raphidascaris sp. (nematodes) in the abdominal cavity. An overall prevalence of 10% (12/120) parasitic infestation was observed. The study showed that prevalence of parasitic infestation during the cold season was 5.2% and the hot season was 14.5%. The highest prevalence of infestation was observed in Oreochromis niloticus (16.7%) followed by Lates niloticus (9.1%) and Clarias anguillaris (5.0%). A total of 360 isolates (188 in the cold season and 172 in the hot season) were characterized and identified as 24 species of bacteria belonging to 15 families. This study is an important contribution to the knowledge of the bacterial and parasitological flora of fish along the value chain sold on the Medina Coura Market, and contributes, to my knowledge as the first attempt to evaluate the microbiological quality of these freshwater fish along the fish value chains.Item Prevalence, Perceived Barriers, Predictors And Associated Biomarkers Of Weight Loss Maintenance Success Among Previous Participants Of A Commercial Weight Loss Programme In Accra, Ghana.(University of Ghana, 2020-07) Addo, S.A.ABSTRACT Background: Weight Loss Maintenance (WLM) although necessary for the preservation of the health benefits derived from weight loss, is difficult to attain. Research investigating the perceived barriers and predictors of WLM success as well as the impact of WLM success on cardiovascular related biomarkers are usually limited to short-term post weight loss periods not exceeding two years. Studies on commercial weight loss programmes are mostly limited to short-term efficacy studies with little known about the long-term outcomes. Additionally, investigations on WLM so far, are mostly carried out in developed countries with no data on WLM outcomes of commercial weight loss programmes in developing countries such as Ghana, and the associated factors of WLM success. Given the global importance of commercial programmes for weight loss, there is the need to gain insight into their long-term outcomes in developing countries including Ghana, and determine the perceived barriers, predictors, and the associated biomarkers of WLM success. Methods: A retrospective cohort study involving 230 participants who formerly enrolled in a commercial weight loss programme between 2008 and 2016 was undertaken in Accra, Ghana. The prevalence of WLM success was determined using a definition of successful WLM as achieving ≥ 5.0% weight loss below starting weight for a period of at least six months post weight loss intervention and unsuccessful WLM as otherwise. An interviewer-administered questionnaire was used to obtain information on the demographic, behavioural, psychosocial and programme based characteristics of participants as well as the perceived barriers to WLM success. A sub-sample of 112 individuals were selected for biochemical analysis on fasting blood lipids and glucose parameters. Categorical Principal Component Analysis (CATPCA) was employed to determine the various components of perceived healthy eating and physical activity related barriers to WLM success. Multivariate binary logistic regression analysis was conducted to identify the predictors of WLM success. Multiple linear regression was used to determine the association between WLM and the concentrations of lipids/glucose biomarkers. Results: The prevalence of WLM success was 23.9%. The healthy eating related barriers to WLM success were locational, cost of healthy eating, food craving, emotional factors and lack of social support and accounted for 66.9% of the variance in data. The physical activity related barriers to WLM success were the cost of physical activity, environmental factors and personal factors and accounted for 65.6% of the variance in data. Achieving ≥ 10% weight loss at the end of the weight reduction programme increased the odds of WLM success compared to not achieving ≥10.0% weight loss (AOR = 6.72, 95.0% C.I = 3.15-14.31). Similarly, logging physical activity compared to not logging (AOR = 3.52, 95.0% C.I = 1.49-8.32), limiting food portions at meal times compared to not limiting (AOR = 3.51, 95.0% C.I = 1.07-11.57), and a good/excellent perceived competence in carrying out behaviours for weight maintenance compared to a poor/disappointing perceived competence (AOR = 5.93, 95.0% C.I = 1.74-20.19), increased the odds of successful WLM. Being out of the weight loss treatment for three years or more as at the time of this study reduced the odds of WLM success compared to being out of treatment for less than three years (AOR = 0.46, 95.0% C.I = 0.22-0.97). Successful Weight Loss Maintainers (SWLM) compared to Unsuccessful Weight Loss Maintainers (UWLM) had significantly lower concentrations of adjusted serum total cholesterol (TC) (5.69±0.24mmol/L versus 6.26±0.18mmol/L, respectively, P<0.013) and triglycerides (TG) (1.11±0.10mmol/L versus 1.34±0.07mmol/L, respectively, P<0.021). SWLM with 10.0% or more weight loss had significantly lower concentrations of adjusted LDL compared to UWLM (3.86±0.31mmol/L versus 4.46±0.18mmol/L, respectively, P = 0.046). The adjusted serum High Density Lipoprotein (HDL), Fasting Blood Glucose (FBG) and glycosylated haemoglobin (HbA1c) concentrations did not differ between SWLM and UWLM. Conclusions: About a quarter (23.9%) of study participants were successful at WLM. Perceived priority barriers to WLM success were costs of healthy eating and physical activity, locational factors and food craving. Participants with varying baseline demographic backgrounds, previous weight loss attempt history and physical activity may be targeted for WLM. A high magnitude of weight loss (≥10.0%) achieved at the weight loss phase predicted WLM success. After the weight loss period, logging of physical activity, limiting food portions at meal times, and a good/excellent perceived competence in carrying out weight management behaviours increased the odds of WLM success. A longer time out of the weight loss programme (three years or more) decreased the odds of successful WLM. SWLM compared to UWLM had significantly lower levels of serum TC and TG but similar HDL, FBG, HbA1C levels. Additionally, SWLM with 10.0% or more weight loss had significantly lower LDL levels compared to UWLM.Item Prevalence, Perceived Barriers, Predictors And Associated Biomarkers Of Weight Loss Maintenance Success Among Previous Participants Of A Commercial Weight Loss Programme In Accra, Ghana.(University of Ghana, 2020-07) Addo, S.A.ABSTRACT Background: Weight Loss Maintenance (WLM) although necessary for the preservation of the health benefits derived from weight loss, is difficult to attain. Research investigating the perceived barriers and predictors of WLM success as well as the impact of WLM success on cardiovascular related biomarkers are usually limited to short-term post weight loss periods not exceeding two years. Studies on commercial weight loss programmes are mostly limited to short-term efficacy studies with little known about the long-term outcomes. Additionally, investigations on WLM so far, are mostly carried out in developed countries with no data on WLM outcomes of commercial weight loss programmes in developing countries such as Ghana, and the associated factors of WLM success. Given the global importance of commercial programmes for weight loss, there is the need to gain insight into their long-term outcomes in developing countries including Ghana, and determine the perceived barriers, predictors, and the associated biomarkers of WLM success. Methods: A retrospective cohort study involving 230 participants who formerly enrolled in a commercial weight loss programme between 2008 and 2016 was undertaken in Accra, Ghana. The prevalence of WLM success was determined using a definition of successful WLM as achieving ≥ 5.0% weight loss below starting weight for a period of at least six months post weight loss intervention and unsuccessful WLM as otherwise. An interviewer-administered questionnaire was used to obtain information on the demographic, behavioural, psychosocial and programme based characteristics of participants as well as the perceived barriers to WLM success. A sub-sample of 112 individuals were selected for biochemical analysis on fasting blood lipids and glucose parameters. Categorical Principal Component Analysis (CATPCA) was employed to determine the various components of perceived healthy eating and physical activity related barriers to WLM success. Multivariate binary logistic regression analysis was conducted to identify the predictors of WLM success. Multiple linear regression was used to determine the association between WLM and the concentrations of lipids/glucose biomarkers. Results: The prevalence of WLM success was 23.9%. The healthy eating related barriers to WLM success were locational, cost of healthy eating, food craving, emotional factors and lack of social support and accounted for 66.9% of the variance in data. The physical activity related barriers to WLM success were the cost of physical activity, environmental factors and personal factors and accounted for 65.6% of the variance in data. Achieving ≥ 10% weight loss at the end of the weight reduction programme increased the odds of WLM success compared to not achieving ≥10.0% weight loss (AOR = 6.72, 95.0% C.I = 3.15-14.31). Similarly, logging physical activity compared to not logging (AOR = 3.52, 95.0% C.I = 1.49-8.32), limiting food portions at meal times compared to not limiting (AOR = 3.51, 95.0% C.I = 1.07-11.57), and a good/excellent perceived competence in carrying out behaviours for weight maintenance compared to a poor/disappointing perceived competence (AOR = 5.93, 95.0% C.I = 1.74-20.19), increased the odds of successful WLM. Being out of the weight loss treatment for three years or more as at the time of this study reduced the odds of WLM success compared to being out of treatment for less than three years (AOR = 0.46, 95.0% C.I = 0.22-0.97). Successful Weight Loss Maintainers (SWLM) compared to Unsuccessful Weight Loss Maintainers (UWLM) had significantly lower concentrations of adjusted serum total cholesterol (TC) (5.69±0.24mmol/L versus 6.26±0.18mmol/L, respectively, P<0.013) and triglycerides (TG) (1.11±0.10mmol/L versus 1.34±0.07mmol/L, respectively, P<0.021). SWLM with 10.0% or more weight loss had significantly lower concentrations of adjusted LDL compared to UWLM (3.86±0.31mmol/L versus 4.46±0.18mmol/L, respectively, P = 0.046). The adjusted serum High Density Lipoprotein (HDL), Fasting Blood Glucose (FBG) and glycosylated haemoglobin (HbA1c) concentrations did not differ between SWLM and UWLM. Conclusions: About a quarter (23.9%) of study participants were successful at WLM. Perceived priority barriers to WLM success were costs of healthy eating and physical activity, locational factors and food craving. Participants with varying baseline demographic backgrounds, previous weight loss attempt history and physical activity may be targeted for WLM. A high magnitude of weight loss (≥10.0%) achieved at the weight loss phase predicted WLM success. After the weight loss period, logging of physical activity, limiting food portions at meal times, and a good/excellent perceived competence in carrying out weight management behaviours increased the odds of WLM success. A longer time out of the weight loss programme (three years or more) decreased the odds of successful WLM. SWLM compared to UWLM had significantly lower levels of serum TC and TG but similar HDL, FBG, HbA1C levels. Additionally, SWLM with 10.0% or more weight loss had significantly lower LDL levels compared to UWLM.Item Prevalence, Perceived Barriers, Predictors And Associated Biomarkers Of Weight Loss Maintenance Success Among Previous Participants Of A Commercial Weight Loss Programme In Accra, Ghana.(University of Ghana, 2020-07) Sandra, A. A.ABSTRACT Background: Weight Loss Maintenance (WLM) although necessary for the preservation of the health benefits derived from weight loss, is difficult to attain. Research investigating the perceived barriers and predictors of WLM success as well as the impact of WLM success on cardiovascular related biomarkers are usually limited to short-term post weight loss periods not exceeding two years. Studies on commercial weight loss programmes are mostly limited to short-term efficacy studies with little known about the long-term outcomes. Additionally, investigations on WLM so far, are mostly carried out in developed countries with no data on WLM outcomes of commercial weight loss programmes in developing countries such as Ghana, and the associated factors of WLM success. Given the global importance of commercial programmes for weight loss, there is the need to gain insight into their long-term outcomes in developing countries including Ghana, and determine the perceived barriers, predictors, and the associated biomarkers of WLM success. Methods: A retrospective cohort study involving 230 participants who formerly enrolled in a commercial weight loss programme between 2008 and 2016 was undertaken in Accra, Ghana. The prevalence of WLM success was determined using a definition of successful WLM as achieving ≥ 5.0% weight loss below starting weight for a period of at least six months post weight loss intervention and unsuccessful WLM as otherwise. An interviewer-administered questionnaire was used to obtain information on the demographic, behavioural, psychosocial and programme based characteristics of participants as well as the perceived barriers to WLM success. A sub-sample of 112 individuals were selected for biochemical analysis on fasting blood lipids and glucose parameters. Categorical Principal Component Analysis (CATPCA) was employed to determine the various components of perceived healthy eating and physical activity related barriers to WLM success. Multivariate binary logistic regression analysis was conducted to identify the predictors of WLM success. Multiple linear regression was used to determine the association between WLM and the concentrations of lipids/glucose biomarkers. Results: The prevalence of WLM success was 23.9%. The healthy eating related barriers to WLM success were locational, cost of healthy eating, food craving, emotional factors and lack of social support and accounted for 66.9% of the variance in data. The physical activity related barriers to WLM success were the cost of physical activity, environmental factors and personal factors and accounted for 65.6% of the variance in data. Achieving ≥ 10% weight loss at the end of the weight reduction programme increased the odds of WLM success compared to not achieving ≥10.0% weight loss (AOR = 6.72, 95.0% C.I = 3.15-14.31). Similarly, logging physical activity compared to not logging (AOR = 3.52, 95.0% C.I = 1.49-8.32), limiting food portions at meal times compared to not limiting (AOR = 3.51, 95.0% C.I = 1.07-11.57), and a good/excellent perceived competence in carrying out behaviours for weight maintenance compared to a poor/disappointing perceived competence (AOR = 5.93, 95.0% C.I = 1.74-20.19), increased the odds of successful WLM. Being out of the weight loss treatment for three years or more as at the time of this study reduced the odds of WLM success compared to being out of treatment for less than three years (AOR = 0.46, 95.0% C.I = 0.22-0.97). Successful Weight Loss Maintainers (SWLM) compared to Unsuccessful Weight Loss Maintainers (UWLM) had significantly lower concentrations of adjusted serum total cholesterol (TC) (5.69±0.24mmol/L versus 6.26±0.18mmol/L, respectively, P<0.013) and triglycerides (TG) (1.11±0.10mmol/L versus 1.34±0.07mmol/L, respectively, P<0.021). SWLM with 10.0% or more weight loss had significantly lower concentrations of adjusted LDL compared to UWLM (3.86±0.31mmol/L versus 4.46±0.18mmol/L, respectively, P = 0.046). The adjusted serum High Density Lipoprotein (HDL), Fasting Blood Glucose (FBG) and glycosylated haemoglobin (HbA1c) concentrations did not differ between SWLM and UWLM. Conclusions: About a quarter (23.9%) of study participants were successful at WLM. Perceived priority barriers to WLM success were costs of healthy eating and physical activity, locational factors and food craving. Participants with varying baseline demographic backgrounds, previous weight loss attempt history and physical activity may be targeted for WLM. A high magnitude of weight loss (≥10.0%) achieved at the weight loss phase predicted WLM success. After the weight loss period, logging of physical activity, limiting food portions at meal times, and a good/excellent perceived competence in carrying out weight management behaviours increased the odds of WLM success. A longer time out of the weight loss programme (three years or more) decreased the odds of successful WLM. SWLM compared to UWLM had significantly lower levels of serum TC and TG but similar HDL, FBG, HbA1C levels. Additionally, SWLM with 10.0% or more weight loss had significantly lower LDL levels compared to UWLM.Item Development and Validation of a Photographic Food Atlas with Portion Sizes of Commonly Consumed Animal And Plant Protein Source Foods in the Greater Accra Metropolitan Area(University of Ghana, 2020-10) Kuevi, A.D.Background: Accurate estimation of food portion size among free-living persons during dietary assessment is a common challenge. The weighed food intake presently regarded as the gold standard method is time and resource intensive with a high respondent burden. Retrospective methods such as the food frequency and 24-hour dietary recall where portion size estimation aids are employed in lieu of weighing are thus more frequently used. Among the portion size estimation aids, there is accumulated evidence that photographic food atlases are highly convenient and effective. So far, the only one based on the Ghanaian diet covers carbohydrate foods. Aim: To develop and validate a photographic atlas for portion size estimation of commonly consumed animal and plant protein source foods in the Ghanaian diet. Method: Fifty-four commonly consumed animal and plant protein source foods were identified in a cross-sectional survey among 834 adult residents (age £18 years) in Greater Accra Metropolitan Area. Colour photographs of each food in graduated portions of between 1 and 8 were produced and bound. Following a pilot study (n=50), the atlas was validated by the visual perception method in which 127 participants from the cross-sectional study estimated 47 predetermined portions of 12 test foods by comparing them with portions shown in photo series from the atlas. Participants’ estimations were categorized as correct (if the exact/correct picture of portion displayed was selected), adjacent (if picture immediately before or after the correct picture was selected) or distal (any other selections). Correct and adjacent estimations were classified as acceptable. Differences in proportions of accurate (correct) and acceptable (correct and adjacent) estimations across sex, age group, BMI and educational status were examined by Pearson’s chi square test of independence at p£0.05. Results: A total of 5894 references to 54 commonly consumed protein source foods were found in the 3-day 24HDR assessments. Fish and sea foods were most frequently consumed (34.6% of total protein food consumption occasions) followed by poultry (21.3%), legumes (18.8%), meat and meat products (13.6%), milk and milk products (11.7%). The atlas produced comprises 62 sets of serial, guide and range photos. In the validation, participants with tertiary education made a significantly higher proportion of accurate estimations than those with no formal education, primary or secondary school education. The proportion of accurate and acceptable estimations also differed according to the size of portion evaluated. Small portions were generally better estimated than large portions. No evidence of statistically significant differences in the proportions of accurate or acceptable estimations was found across sex, age group or BMI. Participants found amorphous foods challenging to estimate. In this regard, evaporated milk was the most difficult: nearly half (48.4%) of its portion size estimations were distal. The proportion of accurate (exact/correct) estimations observed for the 12 test foods ranged from 19.3% (fried tilapia fingerlings) to 88% (grilled sausage) while acceptable estimations ranged from 51% (evaporated milk) to 95.8% (boiled egg). Conclusion: In this study, a high proportion (i.e. 80%) of the 5969 portion size evaluations made during validation corresponded to either the correct portion or the one directly adjacent to it. Based on these results, the atlas produced is a potentially useful tool for portion size estimation of animal and plant protein source foods in the Ghanaian diet.Item Microbial Inactivation by Gamma Irradiation of Powdered Sun-Dried Legon-18 Pepper (CAPSICUM ANNUUM L.) and its Impact on Product Quality(University Of Ghana, 2019-07) Odai, B.T.Pepper powder (being a spice) has been known to be contaminated with several pathogenic microorganisms. These organisms tend to make red pepper powder a source of potential health hazard. The FAO/WHO preliminary report indicated a global concern on the management of these pathogens in foods and the need to reduce or eliminate the health hazards associated with them. Some of these pathogens have been identified with both dried and powdered pepper samples in Ghana. This warranted a study to investigate the use of gamma irradiation on these pathogens in Legon-18 (Capsicum annuum L.) pepper powder and also to determine the impact of the gamma radiation treatment on the quality parameters of the samples stored at two different temperatures. Samples of powdered Legon-18 pepper were obtained from a local farmer. Known weights of the samples were sterilised by gamma irradiation at 20 kGy, and a cocktail of Listeria monocytogenes, Bacillus cereus, Salmonella Typhimurium, Staphylococcus aureus and Escherichia coli of pre-determined cell count (colony forming unit/millilitre), were inoculated into them. The samples were irradiated at 1, 2, 4, and 5 kGy with 0 kGy as control, to determine an effective dose of gamma irradiation that could lead to complete inactivation of the pathogens inoculated in the samples. The samples were stored at 4 oC and 28±2 oC. Enumeration of the different pathogens was carried out on days 0, 2, 5, 12, 21, 30, 45 and 60 in storage. The effects of gamma irradiation and storage on the quality parameters of unsterile samples were determined. These were irradiated at 1, 2, 4 and 5 kGy. Unirradiated samples served as control (0 kGy). The CIELAB colour components were determined using the Minolta Chroma-meter. Carotenoids and capsaicinoids in the samples were quantified using high performance liquid chromatography. The results suggest that gamma irradiation treatment completely inactivated L. monocytogenes and S. Typhimurium only at day 60 at 2 and 4 kGy. E. coli could not thrive in the samples after 30 days of storage when not exposed to gamma irradiation. S. aureus could be completely inactivated at 4 kGy only after 45 days (no detection of S. aureus in the samples after). All the pathogens could be completely inactivated at 2, 4 and 5 kGy. The optimum dose for complete inactivation of the pathogens excluding B. cereus was 2 kGy which is subject to a storage period of over 45 days. All pathogens used in the study were completely inactivated at 5 kGy even on day zero. Gamma irradiation treatments and storage significantly (p<0.05) affected the quality parameters of the samples. Losses of colour parameters, carotenoids and capsaicinoids were more pronounced in the samples that were stored at 28±2 oC as compared with the samples that were stored at 4 oC. Percentage losses for the samples stored at 4 oC were in the range of 83.32 and 83.81%, 50.00% to 53.72%, 33.53% to 37.80%, 54.52% to 58.60%, 40.25% and 56.00%, 78.35 to 81.71% and percentage increase in the range of 372.36% to 429.14% for lightness, redness, yellowness, browning index, chroma, hue and total colour difference respectively. The total colour difference, hue, chroma, browning index, yellowness, redness and lightness of the samples that were stored at 28±2 oC were in the range of 410.72% to 417.50%, 80.13% to 84.75%, 39.55% to 57.00 %, 50.69% to 54.02%, 32.98% to 37.37%, 51.86 to 55.06, 72.77 to 76.98% respectively. Moisture content, total titratable acidity and pH of the samples were stable. Capsaicinoid content ranged from 118 in the unirradiated samples to 221.00 (mg/100g) in the irradiated samples. At the end of the storage period there was a loss of 22.46%, 9.95%, 11.78%, 9.86% and 9.53% in the samples that were irradiated at 0, 1, 2, 4and 5 kGy respectively and stored at 4 oC and for the unirradiated samples, 16.43%, 11.11%, 10.31% and 10.67% for the samples that were irradiated at 1, 2, 4 and 5 kGy respectively and stored at 28±2 oC. Gamma irradiation caused an increase of 6.33, 17.68, 18.79 % and 20.95% in the samples irradiated at 1, 2, 4 and 5 kGy respectively. Beta cryptoxanthin, beta carotene and capsanthin ranged from 1.04 to 2.11, 5.36 to 10.27 and 1.12 to 1.48 (mg/100 g) in the irradiated samples, respectively. Gamma irradiation and storage caused some reductions in the contents of all the pigments analysed (p<0.05).Item Effect of Fish Fortified Amaranthus Cruentus and Solanum Macrocarpon Powder on Anaemia and Vitamin A Status of 4 to 8 – Year – Old School Children in Kodzobi, Adaklu District of Ghana.(University Of Ghana, 2019-06) Tohouenou, M.M.Background: Anaemia, vitamin A deficiency and infections are widespread among Ghanaian children of school-going age and are topics of public health concern. Several interventions including supplementation have been implemented over the years to improve the situation, however the problem persists. Globally, food-based approaches have been recognized as more sustainable in addressing micronutrient deficiencies. In Ghana there is a lack of knowledge on using a combination of fish and vegetables powder as a food-based intervention in combating anaemia and vitamin A deficiency. Objective: The research sought to investigate the effect of consumption of fish fortified Amaranthus cruentus and Solanum macrocarpon powder on anaemia and vitamin A status of 4 to 8-year old school children at Kodzobi in Adaklu District of the Volta Region of Ghana. Methods: The study was a randomized controlled trial with data collection point at baseline and end line and a four-month nutrition intervention period. Three groups made up of 54 children each were identified to participate in the study through random sampling. Parental and participant background information was collected using questionnaires. Haemoglobin and serum retinol concentrations were determined using the heamocue haemoglobinometer and the high-performance liquid chromatography respectively. The Giemsa staining and the Kato-Katz techniques were employed to examine malaria-parasitaemia and soil-transmitted helminths infections respectively. Dietary data were collected using the 24-hour recall method and a food frequency questionnaire. Using WHO standard procedures, weight and height measurements were taken to assess participants‟ anthropometric nutritional status. Haematological indices and dietary data were normally distributed so means ± standard deviations were used to present their summary values. Outcome measures of variables (haemoglobin, serum retinol, dietary nutrient intakes, Z - scores) were compared within groups using paired T-test for continuous variables and chi-square for categorical variables. Analysis of co-variance (ANCOVA) was used to test for differences in mean changes among the 3 groups and between paired groups to determine any significant differences. Binary logistic regression was used to determine factors associated with anaemia and vitamin A deficiency whilst adjusting for potential confounders. Results: At baseline, the mean haemoglobin concentration of the two intervention groups A and B and the control group C were 12.0 ± 1.1 g/dl, 11.4 ± 1.0 g/dl and 11.6 ± 1.0 g/dl respectively. At end line, it was 12.4 ± 1.3 g/dl, 11.8 ±1.9 g/dl and 11.6 ± 1.3 g/dl for groups A, B and C respectively. A significant difference in mean haemoglobin concentration was recorded across the groups at p = 0.024 at post-intervention. At baseline, the prevalence of anaemia was 46.3 %, 51.9 % and 42.9 % for groups A, B and C respectively. At the end of the intervention period, the prevalence of anaemia reduced to 34.5 %, 45.2 % 41.2 % for intervention groups A, B and the control group C respectively. The difference in the prevalence of anaemia across the groups was significant at p = 0.036. The mean serum retinol concentrations of the three groups (A, B and C) at baseline were 23.1 ± 7.3 μg/dl, 22.3 ± 5.6 μg/dl and 22.8 ± 6.8 μg/dl respectively. At end line, it increased to 28.3 ± 8.8 μg/dl, 24.7 ± 6.5 μg/dl and 23.8 ± 6.5 μg/dl for groups A, B and C. A significant difference in serum retinol concentration was recorded across the groups at p = 0.044. Prevalence of vitamin A deficiency decreased from 31.5 % to 9.6 % for intervention group A; 29.6 % to 20.0 % for intervention group B and 35.2 % to 29.4 % for the control group C from baseline to end line respectively. Across the groups, differences in vitamin A deficiency (VAD) at the beginning and end of the study were not significant. Malaria was prevalent among the participants at the baseline and at the end of the study. Malaria prevalence declined from baseline to end line within the three groups: group A 46.3 % to 13.5 %; group B 25.9 % to 10.0 % and group C from 38.9 % to 9.8 %, however, the decreases were not statistically significant. Only one participant was reported to have hookworm infestation. Serum retinol level was significantly associated with anaemia. Marital status and anaemia status were the factors significantly associated with vitamin A deficiency. Conclusion: Anaemia and vitamin A deficiency are problems of public health significance in school-aged children in Kodzobi at Adaklu District. Fish fortified Amaranthus cruentus and Solanum macrocarpon powder improved the haemoglobin concentration of participants significantly and so has the potential to reduce anaemia prevalence but not vitamin A status of the study participants.Item Optimisation of the Parameters for Bio-Processing of Cassava Peel to Increase Fermentable Sugars and Lysine Production(University of Ghana, 2017-07) Bayitse, R.Bio-processing of cassava peel for Lysine production was done by characterising the cassava peel for carbohydrate types. The process of enzymatic hydrolysis of the cassava peel was optimised to produce fermentable sugars using response surface methodology. The hydrolysed cassava peel was used as a source of carbon to optimise the conditions for lysine production using mutant Corynebacterium glutamicum (AHP3) strain. Cassava peel is a biomass generated as a result of processing cassava tuber by peeling operations. It is a natural resource that shows heterogeneity in structure and chemical composition. Physical and chemical composition analysis was done using standard methods. It was found that nearly 83 % dry matter (DM) composition of the cassava peel was glucose whiles xylose and arabinose have made up only small amount of 2.31 and 2.35 % respectively. The cellulose and hemicellulose were 6.0 % DM and 2.23 % DM respectively and the residual starch content was 47.16 %. The protein was 2.40 % and the cyanide level was 9.3 mg/kg. The lignin and the ash contents were 1.92% and 6.30% respectively. The high level of residual starch and low amount of lignin make the cassava peel very susceptible to enzymatic hydrolysis without laborious pretreatment regimes. Importantly, this study provides a useful base line data for agro-economic evaluation of cassava peel as a feedstock for an integrated biorefinery, because the valorisation of cassava peel is still overlooked and not fully exploited. Additionally, deep understandings of the biomass chemical and physical characteristics need to be known in order to assist in designing safe processing facilities. Cassava peel is normally considered as waste because of its limited use. Composition analysis revealed that it contained appreciable amount of starch which can be hydrolysed to fermentable sugars. Response Surface Methodology using Central Composite Design (CCD) was applied to optimise the enzymatic hydrolysis of cassava peel in order to produce glucose. Two effective approaches were used in the study. The first one was to optimise the enzymatic hydrolysis process using cellulase, β-glucosidase, amyloglucosidase and α-amylase. The second approach was to optimise enzymatic hydrolysis using the mixture of these enzymes. The effects of enzyme loading, hydrolysis time, substrate concentration, pH and temperature on glucose recovery were investigated. The results were subjected to analysis of variance (ANOVA) to produce polynomial regression model. Mean interaction plot and their effect on glucose recovery were drawn to determine the optimal conditions for enzymatic process. Targeted hydrolysis of specific carbohydrate types in cassava peels with single enzymes showed optimised levels of glucose recovery of over 80% for starch hydrolysing enzymes and about 5% for cellulose hydrolysing enzymes at 0.06 g/ml substrate water ratio at 24 hours of hydrolysis. Single step hydrolysis of cassava peel with mixed enzymes of starch and cellulose hydrolysis enzymes at optimised conditions of celulase (30 FPU/g), β- glucosidase (1.25 U/g), amyloglucosidase (30 U/g), α-amylase (30 U/g), pH 4 and 50 ᵒC at 24 hours produced recovered glucose of about 100%. The present study revealed that lysine biosynthesis from Corynebacterium glutamicum can be significantly enhanced by optimising the fermentation process. Different ingredients have an essential role in the metabolic pathway of the organism for lysine production. Carbon and nitrogen sources from cassava peel hydrolysate have also been found to have influential role in the amino acid production. Central Composite Design (CCD) was applied to optimise the amino acid fermentation process in order to produce lysine. The effects of substrate concentration, microbial load and time of fermentation on growth of C glutamicum, glucose utilisation and lysine production were investigated. The results were subjected to analysis of variance (ANOVA) to produce polynomial regression model. Mean interaction plot and their effect on microbial growth, glucose consumption and lysine production were drawn to determine the optimal conditions for amino acid fermentation process for lysine production. Glucose utilisation reduced at higher hydrolysate concentration thereby affecting microbial growth. Lysine production was optimum at low initial microbial load of 0.05 nm (OD) and cassava peel hydrolysate concentration not more than 35% (v/v) at 48 hours fermentation.Item Association between Obesity and Oral Health in Ghanaian School Children: The Role of Dietary and Oral Hygiene Practices(University Of Ghana, 2015-07) Ndanu, T.ABackground: Obesity is associated with diabetes, hypertension, cardiovascular diseases, caries and periodontal diseases, and other morbidities. The association between childhood obesity and oral disease is, however, not well defined. This study examined the association between obesity and oral health in school children and explored possible dietary and oral hygiene risk factors. The study hypothesized that there was poorer oral hygiene status and higher caries and gum disease among the obese than the non-obese. Also oral bacteria associated with caries and gum diseases would be more common in obese than the non-obese school children. Method: The first phase of the study consisted of a single cross-sectional survey of 547 school children from private schools in Accra made up of 233 obese and 314 non-obese schools children between the ages of 9 and 15 years. Dietary and oral hygiene information were collected and respondents were orally examined by two dental surgeons. The second phase was a case-control design of 493 public school children made of 210 cases of caries and gum diseases, and 283 controls. Bacteria samples were cultured from oral plaque samples collected from 75 obese and 75 non-obese children. Results: Mean age of the school children from the private school was 11.5 ±1.7. Dietary habits and oral hygiene practices as well as caries and gum disease prevalence were similar in the obese and non-obese children. Caries prevalence among the obese was 14.9% and among the non-obese was 15.1%. The caries experience among the 12 years old (WHO index age for caries) obese children was 15.4% and among the non-obese was 8.2%. Gum disease prevalence among the obese was 3.7% and among the non-obese was 5.5%. None of these differences was significant, p>0.05. The overall oral disease (caries and gum disease) prevalence among the children was 19.2% and not different by obesity status. In the public schools, caries experience among the obese children was 33.3% and non-obese was 19.4%. Gum disease among the obese was 38.9% and the non-obese was 33.3%, p=0.620. None of the dietary and oral hygiene factors showed any significant association with the oral conditions in the two groups. Only breakfast intake among the children in the public school was associated with low caries prevalence (p=0.0314). Streptococcus infection was significantly higher in the obese (41.3%) than the non-obese (26.0%) but this did not show any significant association with the caries experience in the two groups. Lactobacillus species was very low (1.3%) but Actinobacillus actinomycetemcometans (aa) among the non-obese was 15.6% and the obese 6.7% but was not significantly different, (p=0.068). Conclusion: Dietary and oral hygiene practices were similar between the obese and the non-obese school children, whether in private or public schools. Similarly, caries and gum disease prevalence were not significantly different in the children irrespective of weight category and obesity status and whether they are in private or the public schools. Oral microbial infections of the four bacteria investigated (Lactobacillus species, P. gingivalis, aa) were similar except for streptococcus mutans which was significantly higher in the obese but was not significantly associated with caries prevalence. Obesity in Ghanaian children was not associated with oral health status.Item Process Optimization and Product Characteristics of White Kenkey (Nsiho)(University of Ghana, 2015-06) Oduro-Yeboah, C.; Saalia, F.K.; Amoa-Awua, W.; Mestres, C.; Sakyi-Dawson, E.; University of Ghana, College of Basic and Applied Sciences School of Biological Sciences Department of Nutrition and Food ScienceKenkey, is a maize based sour, stiff dumpling, and it is among the most common fermented cereal food products in Ghana. There are several types of kenkey, and while some are made from whole maize grains others are produced using degermed/and dehulled maize grains. The kenkey types made using dehulled maize grains are less popular and have largely remained at the level of “ethnic food”, restricted to very few socio-cultural communities. Current trends in urbanization, and the increasing popularity of kenkey among consumers, require larger scale production with consistent quality. The study was carried out to examine the traditional white kenkey process and to optimize the key processing variables in order to obtain reproducible quality white kenkey that will be acceptable to native and non-native consumers. A survey was conducted in three white kenkey production districts to collate information on production, vending and consumption practices. The sensory profile and consumer acceptance of different types of kenkey and other fermented maize products in Ghana were investigated. A total of two hundred consumers including 110 Ghanaians and 90 internationals were used for the consumer test. Traditional white kenkey types were analyzed for their physicochemical, textural, microstructure and sensory characteristics. Physicochemical analysis involved determination of pH, titratable acidity, sugars, lactic acids, minerals, vitamins and amino acids using high performance liquid chromatography procedures. The textural characteristics of white kenkey randomly obtained from traditional processors were determined using instrumental (texture analyser) and consumer assessments. The effects of processing variables of steeping time (12, 30 and 48 h) and dough fermentation time (0, 12 and 24 h) on the physicochemical properties of white kenkey were determined. A (three variable) Box-Behnken design was used to optimize the processing variables of steeping time, steeping temperature, and fermentation time on white kenkey quality parameters of moisture, pH, titratable acidity, glucose and lactic acid content. The optimum region of the process variables was obtained by hedonic tests on the white kenkey using balanced incomplete block design (for k= 5, b= 21, λ=2, r =7) Quantitative Descriptive Analysis (QDA) was conducted on white kenkey made from within and outside the optimum region of the process variables, as well as white kenkey obtained from vendors using a panel of 18 trained members. Consumer acceptance study was conducted using 65 consumers for white kenkey obtained from the optimum region and traditionally processed white kenkey obtained from vendors. The results of the survey showed that there were two main types of white kenkey, nonsweetened white kenkey and sweetened white kenkey to which sugar is added during production. All three procedures involved steeping of dehulled maize grains which is then milled into a meal. In the (procedure at Atimpoku), the meal was not fermented any further but precooked, moulded into balls wrapped in leaves and steamed. In the (procedure at Anum), the meal was kneaded into dough and allowed to ferment for 12hours, the fermented dough (70%) is precooked and mixed with the remaining dough, moulded into balls and steamed. Three classes of behaviours of consumers were identified. Those who liked all the products ‘all likers’ (36%), those who preferred the white kenkey ‘white likers’ (30%) and those who preferred Banku ‘banku likers’ (34%). Sensory attributes important for the white likers were whitish colour, fruity odour, smooth and nonsticky texture, a less sour product without a pronounced fermented odour, and a bland taste. The white kenkey samples randomly obtained from vendors contained 70 – 77 % moisture, 0.58-0.88 g/100 g ash, 0.09-0.19 g/100 g fat, 2.45-2.84 g/100 g protein, vitamin B1 of 17-47 g/100 g, had pH of 4.07 –4.54, titratable acidity 0.42-0.60% lactic acid, 2-28 mg/g glucose, and 0.6-2 mg/g lactic acid. The amino acids lysine, methionine, Gaba and Ornitine values were less than 0.2 g/100g. Steeping time of maize was complimentary to fermentation time since both influenced the conversion of glucose by lactic acid bacteria into lactic acid. Generally, the longer steeping and fermentation times gave higher levels of glucose and lactic acid in the white kenkey. However, whilst steeping increased glucose level, dough fermentation reduced it. The intensity of whiteness (L) in white kenkey diminished as steeping time increased. On the other hand, fermentation time improved whiteness of kenkey. High aflata (i.e ratio of precooked to uncooked dough) produced kenkey with softer texture, whilst reducing the aflata ratio increased the hardness and stickiness of white kenkey. Consumers preferred white kenkey made using high aflata ratio and steamed for longer periods. The optimization studies showed that processing variables had significant effects on the physicochemical and sensory characteristics of white kenkey. The optimum region for the process variables at which the most acceptable kenkey was obtained were steeping time of 30-45 h at 30-35ºC temperature followed by 12 h dough fermentation. Consumer acceptance test indicated no significant difference in acceptance between the traditionally processed white kenkey samples and those obtained from the optimum region. White kenkey samples of higher quality potential has been identified. The process for production of white kenkey has been standardized, saving production time.Item Evaluation of Traditional Weaning Meals, Supplemented With Protein-Rich Foods to Promote Growth in Malnourished Preschool Children(University of Ghana, 2000-01) Opare-Obisaw, C.; Orraca-Tetteh, R.; Asibey-Berko, E.; Klemesu, M. A.; Sefa-Dedeh, S.; University of Ghana, College of Basic and Applied Sciences, School of Biological Sciences, Department of Nutrition and Food ScienceThis study was aimed at constituting nutritious home-made weaning meals, using local foods that would curtail malnutrition among pre-school children and facilitate a smooth transition from breast milk and cereal porridges to adequate post weaning food consumption. Nine weaning meals were formulated. Three meals each were formulated using comdough, commeal and yam as staple. To one meal in each group of 3 meals, cowpeas, fish or melonseeds were added as the effective source of protein supplement. The same quantities of palm oil, tomatoes, onion and cocoyam leaves were added to each of the meals. Proportions of ingredients were selected so that one third of energy and half of the protein requirements of a 1-3 year old child is met. Considerations were made to incorporate the minimum amount of supplement that would maximize protein nutritional value, at minimum cost, and to provide enough food to suit the stomach capacity of the child at a sitting. Biological utilisation of the protein in the meals was determined by nitrogen retention in rats and compared with casein and koko [a favourite local maize weaning food]. Protein quality determined by using analysed amino acid compositions to calculate amino acid scores, were compared with koko. Protein, fat, energy, vitamin and mineral contents of the meals were also determined. Thirty-five malnourished children aged 1-3 years were assigned to the experimental meals and fed for 4 weeks. Mean weight and height gains as well as increases in haemoglobin levels of the experimental children were determined and compared with those of 10 children, who served as controls. Comparisons of data employed Analysis of Variance or Analysis of Covariance and Tukey’s HSD test where appropriate. Differences were considered significant when the probability of obtaining them was 5% or less. Protein, fat, ash and total energy contents of all the meals were greatly improved over that of koko. Protein concentrations of the meals were satisfactory and adequate to support catch-up growth of 20-30g per day. Energy densities were all well above 85 kcals/lOOg of food, considered adequate for supporting rapid growth. Protein quality as expressed by BV% and NPUop%, although lower than casein values, were significantly higher (P<0.003) than koko values, and supported growth in the essential amino acid compositions showed great improvement upon that of koko. Consequently, the protein scores of the meals ranged from IV2 times to over double that of koko. Except for calcium, the mineral and vitamin contents of the meals were adequate. The mean weight gained by the children in the experimental group was 410 grams, which was significantly higher (p = 0.007) than the gain of 50g by the control group. Irrespective of staple or supplement used, differences in weight gains among the experimental groups were not significant. However, the group fed yam meals gained about twice as much weight as those fed comdough and commeal. The group fed meals supplemented with melonseeds gained about 1/3 more weight than those fed cowpeas and fish. The gains in WAZ and WHZ scores for the experimental group were significantly higher (p = 0.027 and p = 0.40 respectively) than those of the control group. The height gains by the experimental and control groups were not significantly different. The mean increase of 8% in haemoglobin level by the experimental group was significantly higher ((p=0 .012) than the decrease of 1% in the control group. The study has demonstrated that, carefully constituted weaning meals, using local foods can meet energy, protein, mineral, and vitamin needs and are capable of promoting growth even in malnourished children. The meals prepared with comdough and yam are particularly recommended for weaning, because they are not bulky and therefore suit the stomach capacities of young children. The use of melonseeds must be encouraged in meals for young children. Yam, which produces softer meals, must be encouraged for weaning meal preparation, because it yields meals that are as nutritious as meals prepared with cereals, when supplemented with protein-rich foods.Item Molecular Diversity and Technological Properties of Predominant Microorganisms Associated with the Processing of Millet into Fura, A Fermented Food in Ghana(University of Ghana, 2013-12) Owusu-Kwarteng, J.; Tano-Debrah, K.; Jespersen, L.Fura is a millet-based spontaneously fermented dumpling produced and consumed in parts of West Africa, particularly Nigeria, Burkina Faso and Ghana. From eight (8) traditional fura production sites in northern Ghana, lactic acid bacteria (LAB) and yeasts were isolated, characterized and identified using genotypic methods. These included (GTG) 5 -based rep-PCR fingerprinting, sequencing of the 16S rRNA gene, multiplex PCR by means of recA gene sequence comparison and sequencing of D1/D2 region of 26S rRNA genes. Following identification, the predominant LAB were assessed for some technological properties including rates of acidification, exopolysaccharide production, amylase production and bacteriocin activities. The identified yeasts were also assessed for their probiotic potential by measuring tolerance to low pH (2.5), bile salt (0.3% oxgall) and temperature (37°C). Based on the genotypes, the LAB species associated with fura processing include L. fermentum (40.8%), W. confusa (19.0%), L. reuteri (13.9%), P. acidilactici (11.8%), L. salivarius (8.1%) and L. paraplantarum (6.3%). L. fermentum predominated in all fermentations (p< 0.05) and uniformity was observed among production sites regarding the dominance of L. fermentum. L. fermentum and W. confusa were isolated in all production sites and almost at all fermentation stages indicating that they are indigenous to traditional fura processing. The yeast species identified include Candida krusei (60%), Kluyveromyces marxianus (38%), Candida tropicalis (0.6%), Candida rugosa (0.2%), Candida fabianii (0.4%), Candida norvegensis (0.6%) and Trichosporon asahii (0.4%). C. krusei and K. marxianus were found to be the dominant species throughout the fermentation and were isolated from all production sites. Generally, majority of predominant LAB strains showed faster acidification rates, high exopolysaccharides production and the ability to inhibit pathogens through the production of bacteriocins. Yeasts isolated from fura survived and grew at human gastrointestinal conditions of pH 2.5 and 0.3% (w/v) oxgall at 37°C over 4 h duration. Additionally, strains of C. krusei, K. marxianus, C. rugosa and T. asahii were able to increase the relative TEER of Caco-2 monolayers after 48 h, making them possible candidates for the development of starter/co-cultures with probiotic potentials. The study has shown the diversity of microorganisms associated with fura processing. It has also revealed the technological properties of the microorganisms that impact on the product and therefore provided the basis for development of starter cultures.Item Microbial Growth Responses in Fermented Maize Dough Systems(University of Ghana, 2004-10) Halm, M.Food safety and the occurrence of diarrhoea are a challenge in the management of food systems in Africa. Infections arising from diarrhoea can be very devastating on the population, especially children. The traditional fermented maize dough systems have been identified as being able to reduce considerably the growth of diarrhoeal causing organisms and improve safety The study was set up to investigate: 1. The survival of selected diarrhoeal causing bacteria (Salmonella, Shigella and Escherichia coli) in maize dough fermenting systems (steeping water, maize dough, Ga kenkey water and maize dough porridge koko) to determine the safety of the products; 2. The survival of four Escherichia coli strains in synthetic medium containing lactic and acetic acids; 3. Tolerance of the dominant yeasts (Candida krusei and Saccharomyces cerevisiae) involved in maize fermentation for lactic acid. 4. Changes in short-term intracellular pH of single cells of Candida krusei and Saccharomyces cerevisiae in the presence of high and low concentrations of lactic acid to explain their tolerance for lactic acid. Five Salmonella species, three Shigella species, five pathogenic Escherichia coli strains and two non-pathogenic strains were inoculated into fermented maize dough systems at a concentration of 106 - 107 cfu/ml at 28 °C. Viable cells were recovered on selective and non-selective media. Almost all the bacteria survived in maize steeping water for 48 h without reduction in numbers. All the salmonellae and shigellae and two E. coli strains were completely inhibited in fermenting maize dough after 48 hours whilst three E. coli strains (026 (VTEC), 0157 (VTEC II) and 03 EAggEC) survived for 48 h but were significantly reduced by more than 3 log units. None of the Salmonella strains survived in koko for 24 h but Sh. flexneri 2a II and four pathogenic E. coli strains (0157 (VTEC II), 026 (VTEC), 03 (EAggEC), 0111 (EPEC)) and one laboratory strain E. coli K12, survived in koko for 48 h with less than 2 log reductions. All the bacteria were completely inhibited in kenkey water after 24 h. The decrease in populations of the bacteria in the different fermentation systems was observed at pH of < 4. Greater numbers of survivors were recovered with non-selective medium than with a selective medium for Gram-negative bacteria. In Trypticase Soy Broth Yeast Extract (TSBYE) supplemented with lactic and acetic acids in concentrations found in fermented maize dough systems, E. coli strains 0111 (EPEC), 03 (EAggEC), K12 and M23 were inhibited to various extents. Concentrations of 31 - 62 mM, undissociated lactic acid had only a bacteriostatic effect on the four pathogens, while above 62 mM, a bactericidal effect was noted after 24 h. Concentrations of > 17 - 33 mM undissociated acetic acid were required to completely inhibit the four E. coli strains. These results confirm that fermented maize dough systems have antimicrobial properties which may inhibit the survival of some pathogenic and non-pathogenic bacteria. The extent of inhibition varied among the species investigated, namely Salmonella, Shigella and Escherichia coli; and also among the maize dough systems. The presence of lactic acid at low pH was found to be the main anti-microbial property of the fermented maize dough systems. The influence of different lactic acid concentrations (0.2, 0.4, 0.8 and 1.2% V/V), within a pH range of 3.5 to 4.2 on the survival kinetics of E. coli 0111: H2 (EPEC) was determined in TSBYE at 30 °C. Survival data were analysed and fitted with the model of Peleg and Cole (1998). The model parameters b and n were estimated and used to calculate the time to one log decrease in bacterial population. The model of Peleg and Cole gave a good description of the survival of E. coli under the experimental conditions tested. A strong correlation of the time to one log reduction in bacterial numbers with the undissociated lactic acid concentration was demonstrated. Also using the Number Cruncher Statistical Sytems (NCSS), a multiple regression analysis was performed on the data and a model was obtained which relates the death rate (time to one log reduction) to the lactic acid concentration and pH. The proposed model for the death rate of E. coli 0111 (EPEC) in response to pH and total lactic acid concentration in TSBYE provided a good description of the data. Except for the low pH of 3.5 and 1.2% lactic acid, where the model predicted a negative value for the death rate, all other predicted values were in agreement with actual values obtained in the broth studies. Growth responses of two strains each of Candida krusei and Saccharomyces cerevisiae singly and as mixed cultures were determined in MYGP broth, pH 2.5 and pH 3.5 with or without lactic acid at 30 °C. At pH 2.5, in the presence of 106.4 mM undissociated lactic acid, C. krusei strains grew within 48 h from 4.0 log10 cfu/ ml to 7.0 logio cfu/ ml irrespective of whether cultured singly or combined as mixed cultures with either strain of Sacch. cerevisiae. But Sacch. cerevisiae strains did not grow when cultured individually in combination with either strain of the two C. krusei investigated. When the Sacch. cerevisiae strains were cultured individually as single cultures only one grew at pH 2.5 in the presence of 106.4 mM undissociated lactic acid. At pH 3.5, irrespective of the presence or absence of 77 mM lactic acid, C. krusei 29 grew from 4.0 logio cfu/ml to about 8.0 logio cfu/ml whether cultured singly or in combination with either strain of Sacch. cerevisiae. In contrast, both strains of Sacch. cerevisiae showed good growth as single cultures but reduced growth when cultured with C. krusei as mixed cultures and the reduced growth was greater in the presence of lactic acid. These results indicate that C. krusei is more tolerant to lactic acid at low pH than Sacch. cerevisiae. To explain the differences in lactic acid tolerance of the two yeast species, fluorescence-ratio-imaging microscopy and a perfusion system were used to determine the short-term intracellular pH (pH,) changes in single cells of C. krusei and S. cerevisiae. The changes were investigated both in the presence of low (20.7 mM) and high (106.4 mM) concentrations of undissociated lactic acid. For both the investigated species 20.7 mM undissociated lactic acid did not seem to influence the initial pH; which for C. krusei was found to be approx. 8.0 and for S. cerevisiae 6.9- 7.5. For both C. krusei strains, perfusion with 106.4 mM undissociated lactic acid induced only weak short-term pH responses with a decrease in pH of less than one pH unit. Contrary for both strains of Sacch. cerevisiae, perfusion with 106.4 mM undissociated lactic acid resulted in a significant decrease in pH from initially 6.9 – 7.5 to 6.2 - 6.4 after 1 min and further to a pH, of < 5.5 after 3 min after which it remained constant. The results obtained show that C. krusei is more resistant to short-term pHj changes caused by lactic acid than S. cerevisiae, and this, in turn, may explian why C. krusei is more tolerant to lactic acid than S. cerevisiae.