Department of Nutrition and Food Science
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Item Physicochemical, Functional Properties And Mycotoxin Occurrence Of Ghanaian Tigernuts (Cyperus Esculentus L.)(University of Ghana, 2022-06) Battuta-DawlahIn 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 University of Ghana http://ugspace.ug.edu.gh iii 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 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).