Department of Nuclear Agriculture and Radiation Processing
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Item Radiation Preservation of Black Velvet Tamarind (Dialium guineense Wild.)(University of Ghana, 2010-12) Ofosu, D. O.The economic distribution and marketing of the lesser known fruit Dialium guineense Wild in Ghana has been studied using a structured questionnaire and the rapid appraisal system. The seasonality of the fruit (from January to May) makes it abundant in the peak season and rare or not all for the best part of the year. Some fruits also go to waste in the field owing to underexploitation. This thesis provides information on the resident fungi, mycological quality, sorption isotherm, and the effect of gamma irradiation and packaging on the physico-chemical properties of the fruit and the sensory evaluation of the pulp by a taste panel with the view to showing the economical and nutritional potential of the fruit. The resident fungi and mycological quality were assessed by the conventional decimal serial dilution technique and plating on three media (PDA, DG 18 and OGYE). Sorption isotherms at 29±J -c were determined under simulated Environmental Relative Humidity (20, 55, 65, 75, 85, 95%) provided by glycerol: water mixtures; physico-chemical properties were assessed by the method of the Association of Official Analytical Chemists. Descriptive and preference sensory evaluation were administered using prescribed international methods on a hedonic scale. The tamarind markets are in the southern sector of the country, namely Greater Accra, Eastern, Central, Ashanti and Volta Regions with the hub at Ho, Abor and Akatsi in the Volta Region. The local names of the fruit varied from one region to another. The fruit was purchased mostly by adult females (48.25%) followed by school children (37.06%) and adult males (14.68%). The produce is marketed predominantly in polypropylene sacks (81.81 %) with jute sack taking only 3.63% of the packaging. The sizes of the fruit as expected were variable. The pulp did not lose moisture at 75% ERH but lost moisture to the surrounding at ERI-I's 20, 55, and 65% and the same was true for the whole (intact) fruit. The resident fungi in the pulp belonged to 15 fungal species and 7 genera (Aspergillus, Candida, Cladosporium, Fusarium, Penicillium, Neurospora and Rhodotorula). The fungal flora was predominated by Aspergillus (A. alutaceus, A. candidus, A. flavus, A. fum igat us, A. niger, A. sulphureus, A. ustus) followed by Penicillium (P. digitatum, P. expansum) all of which are being recorded for the first time in the fruit of D. guineense. The fruits were also infested with an insect, Ephestia cautella, of economic importance. There was a commensurate drastic reduction in the mould count in the fruit as the irradiation dose increased from 0 to 10kGy. The resident fungi were not however completely eliminated with the variable residual species appearing after 3 months storage in the packaging materials (polypropylene, polyethylene and jute). The presence and isolation of mycotoxinproducing species A. flavus (Aflatoxins), A. alutaceus (Ochratoxins), P. expansum, P. digitatum (Patulin), F verticilloides (fumonisin) leave much to be desired. Packaging did not significantly influence pH and ash content; but influenced total titratable acidity with increasing dose and storage time. The crude fat content decreased with prolonged storage and increasing dose of gamma irradiation while there was no interaction between dose applied, packaging material and storage time. The panelists did not find significant (P>0.05) difference in the parameters tested for acceptance (colour, sweetness, acidity and tenderness) and they found no differences in the packaging material although they slightly preferred produce kept in jute sacks. The practical implications of these findings are discussed in the light of future promotion and preservation of the pulp for industrial use after gamma irradiation.Item Radiation Preservation of Black Velvet Tamarind (Dialium guineense Wild.)(University of Ghana, 2010-12) Ofosu, D.O.The economic distribution and marketing of the lesser known fruit Dialium guineense Wild in Ghana has been studied using a structured questionnaire and the rapid appraisal system. The seasonality of the fruit (from January to May) makes it abundant in the peak season and rare or not all for the best part of the year. Some fruits also go to waste in the field owing to underexploitation. This thesis provides information on the resident fungi, mycological quality, sorption isotherm, and the e ffect 0 f gamma irrad iation and packaging on the phys ico-chem ical properties of the fruit and the sensory evaluation of the pulp by a taste panel with the view to showing the economical and nutritional potential of the fruit. The resident fungi and mycological quality were assessed by the conventional decimal serial dilution technique and plating on three media (PDA, DG 18 and OGYE). Sorption isotherms at 29±J -c were determined under simulated Environmental Relative Humidity (20, 55, 65, 75, 85, 95%) provided by glycerol: water mixtures; physico-chemical properties were assessed by the method of the Association of Official Analytical Chemists. Descriptive and preference sensory eval uation were adrn inistered using prescribed international methods on a hedonic scale. The tamarind markets are in the southern sector of the country, namely Greater Accra, Eastern, Central, Ashanti and Volta Regions with the hub at Ho, Abor and Akatsi in the Volta Region. The local names of the fruit varied from one region to another. The fruit was purchased mostly by adult females (48.25%) followed by school children (37.06%) and adult males (14.68%). The produce is marketed predominantly in polypropylene sacks (81.81 %) with jute sack taking only 3.63% of the packaging. The sizes of the fruit as expected were variable. The pulp did not lose moisture at 75% ERH but lost moisture to the surrounding at ERI-I's 20, 55, and 65% and the same was true for the whole (intact) fruit. The resident fungi in the pulp belonged to 15 fungal species and 7 genera (Aspergillus, Candida, Cladosporium, Fusarium, Penicillium, Neurospora and Rhodotorulai. The fungal flora was predominated by Aspergillus (A. alutaceus, A. candidus, /I. flavus, A. fum igat us, A. niger, A. sulphureus, A. us/us) followed by Penicillium (P. digitatum, P. expansum) all of which are being recorded for the first time in the fruit of D. guineense. The fruits were also infested with an insect, Ephestia cautella, of economic importance. There was a commensurate drastic reduction in the mould count in the fruit as the irradiation dose increased from 0 to IOkGy. The resident fungi were not however completely eliminated with the variable residual species appearing after 3 months storage in the packaging materials (polypropylene, polyethylene and jute). The presence and isolation of mycotoxinproducing species A. flavus (Aflatoxins), A. alutaceus (Ochratoxins), P. expansum, P. digitatum (Patulin), F verticil/oides (fumonisin) leave much to be desired. Packaging did not significantly influence pH and ash content; but influenced total titratable acidity with increasing dose and storage time. The crude fat content decreased with prolonged storage and increasing dose of gamma irradiation while there was no interaction between dose applied, packaging material and storage time. The panelists did not find significant (P>0.05) difference in the parameters tested for acceptance (colour, sweetness, acidity and tenderness) and they found no differences in the packaging material although they slightly preferred produce kept in jute sacks. The practical implications of these findings are discussed in the light of future promotion and preservation of the pulp for industrial use after gamma irradiation.Item Nodulation, Nitrogen Fixation and Biomass Yield of Selected Forage Legume Species in Coastal Savannah Zone of Ghana(University of Ghana, 2017-07) Dien, M.K.Two field experiments were carried out in the major and minor rainy seasons at the BNARI research farm at Kwabenya, Accra, Ghana from July – November, 2016 to investigate nodulation, biomass yield and nitrogen fixation potential of ten forage legumes (Macroptilium atropurpureum, Stylosanthes guianensis, Crotalaria ochroleuca, Pueraria phaseoloides, Centrosema pubescens, Calopogonuim mucunoides, Cajanus cajan, Flemingia macrophylla, Lablab purpurus and Desmodium distortum). Completely randomized block design (RCBD) with four replications of each of the above named forage legumes was used. Sampling was done at eight weeks after planting for all the legume plants for both major and minor rainy seasons. Sub – samples of both maize and legume species for both major and minor rainy seasons were oven dried at 65oc for 72hrs, milled to fine powder and per cent total N analyzed using Kjeldahl Digestion Method at ECO LAB, University of Ghana, Legon. Nitrogen content for each sample was calculated using the per cent N analyzed and nitrogen difference method used in determining the N-fixed by the legume species. Nodules harvested from sampled plants were washed, moped, weighed for both fresh and dry nodule weight, counted for nodule number and sliced for nodule effectiveness for both major and minor rainy seasons. Data collected was subjected to analysis of variance (ANOVA) of RCBD using GENSTAT statistical package version 16 edition and Duncan’s Multiple Range Test (DMRT) used to separate means where significant differences were observed. On the whole, Crotalaria ochroleuca, C. cajan, L. purpureus, D. distortum and M. atropurpureum produced high dry matter yields. However, the highest (6817kg ha-1) and lowest (1747 kg ha-1) mean shoot dry matter yield for the major rainy season was produced by L. purpureus and S. guianensis respectively. The highest mean dry matter yield for the minor rainy season was 255.30 kg ha-1 for C. ochroleuca while the lowest was 110.30 kg ha-1 for C. pubescens. The highest mean total N yield being 144.50 kg N ha-1 was produced by L. purpureus and 47.70 kg N ha-1 being the lowest value was obtained by S. guianensis during the major rainy season. Crotalaria ochroleuca produced the highest N yield with the value 77.96 kg N ha-1 while the lowest N yield of 38.37 kg N ha-1 was produced by C. pubescens during the minor rainy season. The highest and lowest mean number of nodules produced per plant for the major rainy season were 266.50 for C. cajan and 16.5 for C. mucunoides respectively while the highest and lowest mean number of nodules for the minor season were produced by L. purpureus (153.5) and C. pubescens (3.75) respectively. However, the highest and lowest mean effective number of nodules for the major rainy season were produced by C. cajan (238) and C. mucunoides (10) respectively while the highest and lowest values for the minor season were 139 and 2 for L. purpureus and C. pubescens respectively. Cajanus cajan had the highest mean effective nodules (237.75) and F. macrophylla produced the lowest (10.25) effective nodules (EN) for the major season while in the minor season, L. purpureus had the highest EN (139) with C. pubescens having the lowest EN (3.75). The highest total nitrogen derived from atmosphere (Ndfa) for major rainy season was 112.45 kg N ha-1 for L. purpureus and the lowest total Ndfa of 15.64 kg N ha-1 was produced by S. guianensis. The legume species, C. ochroleuca had the highest Ndfa of 52.93 kg N ha-1 whiles C. pubescens produced the lowest Ndfa of 13.35 kg N ha-1 for the minor rainy season. Statistical analysis indicated highly significant (p ≤ 0.001) seasonal effect on most of the parameters measured for the forage legume species except root dry matter and N yields that had non- significant (p ≥ 0.05) seasonal effect. In conclusion, the linear regression between dry weight of effective nodules and Ndfa for each season, showed positive relationship with R2 values of 0.5807 and 0.4513 respectively, implying that increasing dry weight of effective nodules results in increasing NdfaItem Decomposition and Mineralization of Some Organic Residues in Two Contrasting Agro-Ecological Zones(University of Ghana, 2017-07) Tetteh, D.M.Decomposition and mineralization from plant and animal residues are important processes that can improve soil fertility and build–up soil organic matter. Decomposition and mineralization of 5 and 10 t/ha of matured cow dung (CD) in Ada soil series of the coastal savannah agro-ecological zone, as well as 5 and 10 t/ha of artisanal empty fruit bunch (EFB-AT) and industrial empty fruit bunch (EFB-IN) in Kokofu soil series of the semi-deciduous forest agro-ecological zone were studied using pots. The objective of the study was to assess the decomposition and nutrient release patterns of manured CD and EFB-AT and EFB-IN in order to give an estimate of the release patterns and to synchronize the nutrient release to meet the nutrient demands of crops. The study was conducted between February and June 2017. The dry CD at the two application rates were used for the study in Ada soil series, classified as Entisols (USDA classification) by Brammer (1960), which corresponds to Fluvisols under FAO (1970) classification. Also dry EFBs were used for the Kokofu soil series which are classified Ultisols USDA (Brammer, 1960). Dry CD was put in nylon litter bags, and was buried at 8 cm deep in the soil (in the pots) as practised by farmers in the Sege area, where CD is incorporated into the soil on application. Chopped EFBs of 2cm mesh size were put in nylon litter bags, and placed on the surface of soil in the pots as practised by farmers in the Kade area, where EFBs are placed on the soil surface in most oil palm plantations to serve as mulch. The EFB samples were taken from artisanal palm oil producers (EFB-AT) and industrial palm oil producers (EFB-IN). Buried CDs in pots were sampled at 7, 14, 21, 35, 56, 72 and 90 days whiles EFB-AT AND EFB-IN were sampled 7, 14, 21, 35, 56, 72 90,120 and 150 days after being placed on soil surface in pots. Sixty percent (60%) of the initial weight of the CD decomposed within 90 days with no significant difference (t=0.05) in the fractions lost between 5 and 10t/ha by t- test analysis, based on pair comparison. In the case of EFB-AT, about 20% of the 5 t/ha and 50% of 10 t/ha, of the initial weight had decomposed over the 150 days period. For EFB-IN about 78% of the 5 t/ha and 75% of the 10t/ha of the initial weight decomposed over the 150 days period. Comparatively, a t-test analysis, based on pair comparison, showed a significant difference (t=0.08) between the fractions lost by EFB-AT and EFB-IN at the two application levels. The estimated half-life (t ½) for the decomposition of CD were 82 and 99 days for 5 t/ha and 10 t/ha, respectively. For EFB-AT, the estimated half-life were 112 and 130 days for 5 and 10 t/ha, respectively, while for EFB/IN half-life was 83 and 87 days for 5 and 10 t/ha, respectively. Approximately between 10 and 20% of the initial TN content of the CD was released during the 90 days period with significant difference (t=0.07) in the fractions released between 5 and 10t/ha of CD. Similarly, approximately 15-20% of the initial TN of the EFB-AT and between 30 and 38 % of TN in EFB-IN was released during the 150 days period. Based on pair comparison, the difference in the TN released between EFB-AT and EFB-IN was significant (t=0.07) even between the two application rates (5 and10t/ha). Between 30-38% of the initial P content of the CDs was released while about 60% of the EFBs was released with significant difference (t=0.06) in the fractions released between 5 and 10t/ha, and between EFB-AT and EFB-IN. About 90% of the initial K content in EFBs was released while about 40-50% of the initial K content of the CDs was released during the experimental period, with significant difference (t=0.07) in the fractions of K released between 5 and 10t/ha CD and between EFB-AT and EFB-IN.Item Radiation Preservation of Black Velvet Tamarind (Dialium guineense Wild.)(University of Ghana, 2010-12) Odamtten, G.T.The economic distribution and marketing of the lesser known fruit Dialium guineense Wild in Ghana has been studied using a structured questionnaire and the rapid appraisal system. The seasonality of the fruit (from January to May) makes it abundant in the peak season and rare or not all for the best part of the year. Some fruits also go to waste in the field owing to underexploitation. This thesis provides information on the resident fungi, mycological quality, sorption isotherm, and the e ffect 0 f gamma irrad iation and packaging on the phys ico-chem ical properties of the fruit and the sensory evaluation of the pulp by a taste panel with the view to showing the economical and nutritional potential of the fruit. The resident fungi and mycological quality were assessed by the conventional decimal serial dilution technique and plating on three media (PDA, DG 18 and OGYE). Sorption isotherms at 29±J -c were determined under simulated Environmental Relative Humidity (20, 55, 65, 75, 85, 95%) provided by glycerol: water mixtures; physico-chemical properties were assessed by the method of the Association of Official Analytical Chemists. Descriptive and preference sensory eval uation were adrn inistered using prescribed international methods on a hedonic scale. The tamarind markets are in the southern sector of the country, namely Greater Accra, Eastern, Central, Ashanti and Volta Regions with the hub at Ho, Abor and Akatsi in the Volta Region. The local names of the fruit varied from one region to another. The fruit was purchased mostly by adult females (48.25%) followed by school children (37.06%) and adult males (14.68%). The produce is marketed predominantly in polypropylene sacks (81.81 %) with jute sack taking only 3.63% of the packaging. XIV xv The sizes of the fruit as expected were variable. The pulp did not lose moisture at 75% ERH but lost moisture to the surrounding at ERI-I's 20, 55, and 65% and the same was true for the whole (intact) fruit. The resident fungi in the pulp belonged to 15 fungal species and 7 genera (Aspergillus, Candida, Cladosporium, Fusarium, Penicillium, Neurospora and Rhodotorulai. The fungal flora was predominated by Aspergillus (A. alutaceus, A. candidus, /I. flavus, A. fum igat us, A. niger, A. sulphureus, A. us/us) followed by Penicillium (P. digitatum, P. expansum) all of which are being recorded for the first time in the fruit of D. guineense. The fruits were also infested with an insect, Ephestia cautella, of economic importance. There was a commensurate drastic reduction in the mould count in the fruit as the irradiation dose increased from 0 to IOkGy. The resident fungi were not however completely eliminated with the variable residual species appearing after 3 months storage in the packaging materials (polypropylene, polyethylene and jute). The presence and isolation of mycotoxinproducing species A. flavus (Aflatoxins), A. alutaceus (Ochratoxins), P. expansum, P. digitatum (Patulin), F verticil/oides (fumonisin) leave much to be desired. Packaging did not significantly influence pH and ash content; but influenced total titratable acidity with increasing dose and storage time. The crude fat content decreased with prolonged storage and increasing dose of gamma irradiation while there was no interaction between dose applied, packaging material and storage time. The panelists did not find significant (P>0.05) difference in the parameters tested for acceptance (colour, sweetness, acidity and tenderness) and they found no differences in the packaging material although they slightly preferred produce kept in jute sacks. The practical implications of these findings are discussed in the light of future promotion and preservation of the pulp for industrial use after gamma irradiation.Item Studies Of Essential And Non-Essential Elements In Cereal-Based Weaning Foods For Infants Commercially Available On The Ghanaian Market(University of Ghana, 2013-07) Bawol, S.Cereal-based weaning foods, which abound on the Ghanaian market, are nutritionally vital in the growth and development of infants. Recent reports in scientific literature however indicate that rice and other cereals used in the manufacture of the weaning foods contribute significantly to the intake of arsenic (As), cadmium (Cd) and lead (Pb) by infants. In view of this, frequent monitoring of the cereal-based weaning foods has become imperative. The study assessed the beneficial health effects and risks posed by the consumption of cereal-based weaning foods commercially available on the Ghanaian market with respect to the essential elements (Ca, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Se, V and Zn) and, non-essential, potentially toxic elements (As, Br, Hg, Pb and Sn). Twenty (20) different brands of weaning foods were purchased from various retail outlets in Accra and used for the study. Instrumental neutron activation analysis (INAA) and atomic absorption spectrometry [with flame atomisation (FAAS) and hydride generation (HGAAS)] were used in analysing the samples. Determination of Pb using FAAS was done following its extraction with dithizone. The analytical methods were validated using certified reference materials NIST 1568a (Rice flour) and NIST 1547 (Peach leaves). The levels (μg/g, in ranges) obtained for the elements were: As (< 0.025), Br (<0.17-402), Ca (405-2002), Cl (158-5521) and Cr (<0.03-1.23). Others are: Cu (0.83-55.80), Fe (1.07-11.78), Hg (< 0.025), K (49-3845) Mg (20-280) and Mn (0.84-38.94). The rest include: Na (13-1588), Pb (0.025-0.093), Se (0.145-0.317), Sn (35.8-91.8), V (<0.01-0.990) and Zn (0.50-7.17). The daily intakes of the essential elements were also estimated, and generally found to be lower than recommended values set either by the FAO/WHO, the European Food Safety Authority (EFSA), the US Food and Nutrition Board, or the Joint Societies for Nutrition of Germany, Austria and Switzerland. The estimated intake levels of the non-essential, potentially toxic elements As, Hg, Sn and Pb were all lower than their respective provisional tolerable weekly intake (PTWI) values established by the Joint FAO/WHO Expert Committee on Contaminants and Food Additives (JECFA). The results indicated that the analysed food samples were generally safe for consumption with respect to their content of the non-essential elements analysed. However, the contributions of the food samples to the daily essential element needs of the infant were mostly woefully inadequate, and this may not augur well for the proper growth and development of infants that consume them.Item Investigations Into The Shelf Life And Nutritional Quality Of Fresh Tomato Fruit (Solanum Lycopersicon) Following Two Post - Harvest Treatments(University of Ghana, 2013-07) Gyimah, L.A.Tomato production in Ghana is characterized by a glut and high post – harvest losses during the major season followed by scarcity and high prices during the off season. This is the result or absence of a standard method for preservation of fresh fruits. This research was conducted to determine an effective method for the post - harvest treatment of fresh tomato fruits to enhance shelf life while preserving its physicochemical and nutritional properties. Two experiments were conducted, each with a factorial design of 5x2. In experiment one, the fruits were subjected to 0, 1, 2, 3 and 4 kGy gamma radiation and stored at 10±1ºC and 28±1ºC. In experiment two, CaCl2 dissolved in distilled water at 0, 1.00, 1.50, 2.00 and 2.50 % concentrations were used to coat tomato fruits and stored at 10±1ºC and 28±1ºC. Gamma radiation at 4kGy extended the shelf life of tomato by 5 and 9 days above control when stored at 28±1ºC and 10±1ºC respectively. The use of CaCl2 at 2.50% greatly extended the shelf life of tomato by 11 days and 18 days above control when stored at 28±1ºC and 10±1ºC respectively. For both treatments, shelf life increased with increasing dose of radiation/ concentration of CaCl2. Weight loss was higher in control fruits as well as fruits treated with gamma radiation or CaCl2 coating stored at 28±1ºC temperature than treated fruits stored at 10±1ºC. Tomato fruits treated with gamma radiation at 1 and 2 kGy and untreated fruits showed an increase in pH and Total Soluble Solids (TSS) which was paralleled by a decrease in Total Titratable Acidity (TTA) as storage period advanced at both storage temperatures. However, fruits treated with CaCl2 at 1.00% had little effect on pH and TTA of tomato during the storage period. Nutritionally, CaCl2 coating significantly maintained the vitamin C and lycopene concentrations in tomato fruit more than control and gamma irradiation which reduced vitamin C and lycopene contents in the fruits significantly with days of storage. Storage at 10±1ºC better preserved the antioxidants properties of the fruits better than storage at 28±1ºC. Elemental composition (Na, K, Zn, Cu and Mn) of the tomato fruits analysed on the initial and final days of storage showed K to be the element with the highest concentration whilst Zn was the least. Generally, gamma irradiation led to an increase in the concentration of Na and K for all doses whilst CaCl2 coating significantly decreased the concentrations of the same elements at both storage temperatures. Concentrations of Zn, Cu and Mn reduced significantly in the tomato fruits by the final day of storage for all treatments following storage at 10±1ºC whilst there were inconsistencies in the contents of the elements in tomato fruits stored at 28±1ºC. Gamma radiation and CaCl2 significantly reduced the microbial load in tomato at both temperatures compared to the control. The reduction was proportional to increasing dose of irradiation and concentration of CaCl2. However, CaCl2 significantly reduced Total Aerobic Mesophiles as well as Mould and Yeast growth in tomato fruits compared to gamma irradiation at both temperatures. In general, treated tomato fruits stored at lower temperature (10±1ºC) had more stability and longer shelf life as well as the ability to maintain nutritional properties than those stored at 28±1ºC.Item Effect Of Npk Fertiliser On Growth, Flowering And Yield Of Fonio (Digitaria Exilis) In A Coastal Agro-Ecological Environment Of Ghana(University of Ghana, 2013-07) Amekli, Y.Fonio (Digitaria spp) is a neglected and underutilised crop traditionally grown in the Sahelian savannah agro-ecological zone of Ghana for its grain which is rich in crude protein, fibre and has medicinal properties. Decline in production of the crop is attributed to poor agronomic and yield characteristics and changing agro-climatic conditions as a result of global warming which has rendered traditional growing areas too dry to support cultivation of the crop. There is a need to explore the possibility of growing the crop in new agro-ecologies to sustain the production. The study was therefore conducted in Kwabenya-Atomic area which is located in the coastal savannah agro-ecological zone of Ghana, to evaluate the adaptability of three fonio landraces (Yadema, Nomber and Nvoni) to the coastal zone, their growth and response to NPK 15:15:15 fertiliser treatment, apparent fertiliser nitrogen recovery (AFNR) as well as presence of basic elements, in the grains. Field experiments were conducted in 2012 during the major cropping season, using three fonio landraces grown at a planting distance of 0.05 m 0.45 m. The experiment design used was the split plot in three replicates. Plants were sampled every two weeks throughout the growing season. Grain yield (GY) and its associated apparent fertiliser nitrogen recovery were significantly different (P ≤ 0.05) among the fonio landraces during the cropping season with the landrace Nvoni producing the highest grain yield of 964 kg ha−1 at NPK fertiliser rate of 60 kg ha−1 and with a AFNR of 33.1%. The study also established a positive correlation between biomass accumulation and grain yield. The efficiency of grain production per unit of fertiliser nitrogen (FN) increased, but at a diminishing rate with each additional unit of FN. Additionally, ten essential mineral elements (Na, Mg, K, Ca, I, Cl, Cu, Al, Mn and V) were detected among the grain of the three fonio landrace using Instrumental Neutron Activation Analysis (INAA).Item Development And Preservation Of A Cocktail Beverage Produced From Carrot (Daucus Carrota), Pineapple (Ananas Comosus) And Mango (Mangifera Indica L,)(University of Ghana, 2013-07) Boateng, A.A.Carrot is known to have the potential of providing vital nutrition as well as health and well-being to consumers. In this study, carrot juice was envisaged as a good vehicle for spreading its nutraceutical benefits. The study was then designed in two parts: (a) Survey to establish the beverage consumption pattern in the Anyaa-Sowutuom District in the Greater Accra Region of Ghana and (b) Carrot juice formulation and optimisation. The survey was conducted by administering a questionnaire to volunteer adult consumers. To develop an acceptable carrot juice beverage, pineapple juice and mango juice were included as components to improve taste and flavour respectively. A constrained, simplex centroid mixture design for three components was employed to optimise the proportions of the components in the final product based on sensory attributes. Chemical analyses as well as shelf stability studies were conducted for the optimised beverage preserved by chemicals and gamma radiation. Data obtained from the survey revealed that juices were very popular among consumers. The choice of a particular beverage was dependent on nutrition, taste and colour. Contour plots generated from sensory data of the products were overlaid to determine the optimum ratios of the components of the cocktail beverage. The optimised product consisted of 50-52 % Carrot, 18-20 % Pineapple and 28-30 % Mango. Analysis of the beverage revealed 223 mg/100ml Potassium, 3.92 mg/100ml Pro-vitamin A (Beta carotene) and 43 mg/100ml Vitamin C. After 8 weeks of storage 77 % Pro-vitamin A was retained in products chemically treated and as well as products irradiated at 1 kGy. However, about 60 % of this same nutrient was retained even under relatively higher dose (2.5 kGy) of gamma radiation. The microbial quality of the beverage was good under all conditions studied.Item Effect Of Irradiation On The Shelf Life And Nutritional Quality Of Tomato (Solanum Lycopersicon L.) Powder(University of Ghana, 2013-07) Atuobi-Yeboah, A.A.Tomato (Solanum lycopersicon L.) is a major horticultural crop with an estimated global production of over 153 million metric tons. It is the most important fruit vegetable and the second most widely cultivated crop in the world after potato, with a total production of about 141 million tons. In 2009, the average total yield in Ghana was 7.5 Mt ha-1 compared to the achievable yield of 15.0 Mt ha-1. The tomato industry in Ghana for the past decade has been bedevilled by a myriad of problems of which post-harvest losses range between 30% and 70% in the major seasons of production, hence a study was conducted into the preservation of S. lycopersicon L. through drying and packaging to reduce post-harvest losses. Two drying methods comprising of solar and freeze drying were employed for three varieties of tomato which are cultivated locally. The methods were compared to determine the more efficient for the three varieties used in the study and the impact of drying and radiation on some physico-chemical properties, microbial load as well as shelf-life of the samples. Evaluation of the packaging material for the dried samples was also carried out. The samples were exposed to gamma irradiation at 0 kGy, 1 kGy, 2 kGy and 3 kGy. The parameters determined included moisture content, pH, titratable acidity; total soluble solids total carotenoids, lycopene, lutein and beta carotene. Microbial analysis carried out included total aerobic mesophilic bacteria count, total coliform count and moulds and yeasts using standard methods. Data were analyzed using ANOVA. Storage had significant effect (p<0.05) on the pH, TSS, TTA, colour and microbial load of the various varieties used. Irradiation had a significant effect (p<0.05) on pH, colour, microbial quality, lycopene content, beta carotene, and total carotenoid content of the varieties used; however irradiation had no significant (p>0.05) effect on moisture content, total soluble solids and microbial quality of the varieties used. Comparing powders obtained from freeze dried and solar dried tomatoes (Akoma), solar drying emerged as a more efficient method of drying. In Akoma, significant differences (p<0.05) were observed in all the parameters due to the difference in drying methods. Gamma irradiation did not affect (p>0.05) the moisture content, total soluble solids, of the Akoma variety irrespective of the drying method used. However, gamma irradiation had a significant effect (p<0.05) effect on pH, colour, total aerobic mesophilic counts, total coliforms; moulds and yeast, total carotenoid, lutein and beta carotene. Storage had significant (p<0.05) effect on the colour, total carotenoid content, and lycopene of the powders from the two drying methods. The packaging material used was suitable for the solar dried powder but not the freeze dried powder. Varietal differences (p<0.05) existed between the tomatoes in terms of moisture content, total soluble solids, pH, titratable acidity, colour, total aerobic mesophilic counts, total coliform count and total moulds and yeast counts.
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