Department of Human Nutrition and Consumer Sciences

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Genetic interaction between phaseolus vulgaris and bean common mosaic virus with implications for strain identification and breeding for resistance
(Wageningen, 1978) Drijfliout, E.
DRIJFHOUT, 嚣 TEic Mus with implications for strain identi^-aHon^nd^breeding for resistance. RepJVerllJandbouwk. Onderz.) 872. ISBN 90 220 0671 9. (vii) + 98 p.. summaries. 仙*撷 , 2 加*4两加卅、 Aho: Doctoral thesis, 'Vageningen^ } Various strains of bean common mosaic virus (BCMV) occur in susceptible cultivars of bean. To compare compare these strains, a standard procedure for identification ;ind a set of dif- bean. To ferentiM cultivars were established. The differentials are representatives of 11 resistance Roups'determined groups, < ---------- --- by testing - of about 450 lx?an cultivars with 8 to 10 strains. The virus strains and isolates were classified into 10 pathogenicity groups and subgroups, so that 10 strains were distinguished and the others considered as isolates of those strains. Twelve differentials were intercrossed and their F, and tested with most of the strains for genetical analysis of resistance in bean. Seven genes were distinguished: a necrosis gene /, already known from the literature. 5 strain-specific resistance guncs be』, be」,bc・2, bc-22 and bc・3, and a strain-unspccific gene be*, complementary to the strain-specific ones. Genes hc-1 and he-12 were allelic, as were bc・2 and bc・2:. The 5 loci segregated independently or nearly so. The 4 strain-specific genes bc・l to hc-22 had a gcnc-for-gcnc relationship with 4 pathogenicity genes, likely to be present in the virus strains. Gene bc-3 had not been overcome by a corresponding pathogenicity gene. Two bean genotypes were developed with resistance to all known strains. Some implica tions for resistance breeding arc discussed. Free descriptors: Phaseolus vulgaris, common bean, bean common mosaic virus. BCM V, breeding for resistance, genetics of resistance, iiost 一 virus relationship, pathogenic varimion, screening for resistance, strain identification. This thesis will also be published as Agricultural Research Reports 872. ® Sc 血 Agricultural Publishing and Documentation ,Wageningen, 1978. No Part of this book may be r:r._. rint, micro- reproduced and/or published in any form, by print, photop film or any other means without wri -• written permission from the publishers.
Nutritional evaluation of sorghum as affected by germination with main reference to dietary bulk and protein quality
(Sokoine University of Agriculture, 1984) Mosha, Alexander Clemence
The nutritional value of sorghum as affected by germination and different dehulling techniques was studied with emphasis on protein quality, dietary bulk and food intake. Two low-tannin and two high-tannin varieties were investigated. Nutrient content was affected by germination: minor changes occurred in proximate composition, except for a significant decrease in oil in all varieties. Thiamine, riboflavin and niacin content increased. Lysine increased in all varieties and the other essential amino acids in creased marginally. Dietary fibre was unaffected. Tannin content decreased significantly. Traditional and abrasive dehulling decreased the amount of protein, oil, dietary fibre, minerals, tannins and phytic-phosphorous. protein digestibility was Nutrient availability measured in vitro: significantly higher in the low-tannin varieties. Germination and dehulling increased digestibility in all varieties. Cooking reduced protein digestibility in the high-tannin varieties and significantly more than in the low-tannin cultivars. Iron availability was low in all varieties and increased only in one high-tannin variety after germination. Nutrient availability measured in vivo by rat-bio-assay: protein digestibility was high in low-tannin cultivars but low in high-tannin varieties. Germination increased digestibility only in one high-tannin variety. Biological values were higher in the high-tannin varieties. BV and NPU were not affected by germination. In vivo iron availability was higher in the low-tannin varieties and was increased by germination in only one of the high-tannin varieties. Zinc availability was low and was unaffected by germination and tannin content. Dietary bulk and food intake: When preparing weaning gruels, three times as much germinated flour of the low-tannin varieties, as compared to ungerminated, could be mixed into the same volume, while maintaining the same consistency of the gruel. Germinated flour of high-tannin varieties did not have this effect. Addition of 5% germinated low-tannin sorghum flour (enzyme-rich) to thick ungerminated gruels reduced the viscosity to acceptable weaning food consistency. This method of reducing dietary bulk of weaning food was accepted and used by mothers at village level. Food intake by 12-48 months old preschool children was significantly higher for bulk-reduced low viscosity gruel with 20% solids, compared to untreated gruel. It was concluded that sorghum nutrient content is comparable to other cereals except for the high tannin content. Germination generally improves nutritional value through increased lysine, better protein digestibility and reduction of anti nutritional factors, mainly tannins. The use of bulk-reduced high nutrient density weaning foods could eventually improve the nutritional status of young children.
Thermic effect of food in man: effect of meal composition, and energy content
(British Journal of Nutrition, 1990-02) Kinabo, J. L.; Durnin, J. V. G. A
The effect of meal composition and energy content on the thermic effect of food (TEF) was investigated in sixteen adult, non-obese female subjects. Each subject consumed four different test meals, each meal on a different day. Meals were of high-carbohydrate-low-fat (HCLF) with 0.70, 0.19 and 0.11 of the energy content from carbohydrate, fat and protein respectively, and low-carbohydrate-high-fat (LCHF) with 0.24, 0.65 and 0.11 of the energy content from carbohydrate, fat and protein respectively. The energy contents of the test meals for each composition were 2520 k J (600 kcal) and 5040 k J (1200 kcal). The basal metabolic rate (BMR) and the postprandial metabolic rate (PP-MR) were measured by open-circuit indirect calorimetry using the Douglas bag technique while the subjects were in the supine position. The mean BMR value was 3.63 (SE 0.07) kJ/min (087 kcal/min (SE 0.017)). The 5 h-TEF value for the 2520 k J (600 kcal) HCLF meal was 228 (SE 11.8) k J (54 kcal (SE 2%)) and for the LCHF meal was 228 (SE 9.6) k J (54 kcal (SE 2.3)). The corresponding values for the 5040 k J (1200 kcal) meals were 356 (SE 20.4) k J (85 kcal (SE 4.9)) and 340 (SE 15%) k J (81 kcal (SE 3.8)). There was no significant (P = 049) effect of meal composition on TEF, but the energy content of the meals had a significant (P < 0,001) effect on TEF. In all subjects and for all meals, PP-MR had not returned to premeal level 5 h after a meal, indicating that the TEF values measured underestimate total TEF. The present study suggests that TEF is significantly influenced by the energy content of a meal but not by meal composition.
Thermic effect of food in man: effect of meal composition, and energy content
(1990-02) Kinabo, J. L; Durnin, J. V. G. A
The effect of meal composition and energy content on the thermic effect of food (TEF) was investigated in sixteen adult, non-obese female subjects. Each subject consumed four different test meals, each meal on a different day. Meals were of high-carbohydrate-low-fat (HCLF) with 0.70, 0.19 and 0.11 of the energy content from carbohydrate, fat and protein respectively, and low-carbohydrate-high-fat (LCHF) with 0.24, 0.65 and 0.11 of the energy content from carbohydrate, fat and protein respectively. The energy contents of the test meals for each composition were 2520 k J (600 kcal) and 5040 k J (1200 kcal). The basal metabolic rate (BMR) and the postprandial metabolic rate (PP-MR) were measured by open-circuit indirect calorimetry using the Douglas bag technique while the subjects were in the supine position. The mean BMR value was 3.63 (SE 0.07) kJ/min (087 kcal/min (SE 0.017)). The 5 h-TEF value for the 2520 k J (600 kcal) HCLF meal was 228 (SE 11.8) k J (54 kcal (SE 2%)) and for the LCHF meal was 228 (SE 9.6) k J (54 kcal (SE 2.3)). The corresponding values for the 5040 k J (1200 kcal) meals were 356 (SE 20.4) k J (85 kcal (SE 4.9)) and 340 (SE 15%) k J (81 kcal (SE 3.8)). There was no significant (P = 049) effect of meal composition on TEF, but the energy content of the meals had a significant (P < 0,001) effect on TEF. In all subjects and for all meals, PP-MR had not returned to premeal level 5 h after a meal, indicating that the TEF values measured underestimate total TEF. The present study suggests that TEF is significantly influenced by the energy content of a meal but not by meal composition.
Comparative evaluation of different methods of extraction and purification used in technical enzyme production from microorganisms
(1998) Gidamis, A.B.; Nnko, S.A.; Shayo, N.B.; Chove, B.E.; Kroner, H. K.
A stlldy was conducted to compare the efficiency of two methods of microbial cell separation and enzyme purification using penicillin-G-acylase (PGA) from Escherichia coli. The efficiency of two methods of ceJ[ separation; centrifugation and cross flow filtration (CFF) were compared. The CFF method was found to have both higher separation efficiency and enzyme yield than centrifugation method. Centrifugation method gave a separation efficiency of 98.5% with enzyme yield of94 % whereas CFFmethod resulted in 100% separation efficiency and enzyme yield of98.8%. The Escherichia coli cells were disrupted by high pressure homogenization (HPH),and the disrupted cells were purified using two different techniques. Technique I was a combination of cross-flow-diafiltration (CFD) , ultrafiltration (UF) and heat/pH-shift treatments. This technique resulted in 47% enzyme yield with a purification factor of 12. Technique II which involved two extraction steps by' aqueous two - phase system (APS) coupled with UF resulted in 62 % enzyme yield with a pu;ificationfactor of 4. Technique I was therefore much better than techriique Il in purifying the enzyme. For higher enzyme yield, technique II would seem to be a better one than technique I.
Effects of weaver ants on fruitfly and disease-inflicted postharvest losses of oranges in small-scale farming in Tanzania
(1998) Msogoya, T.J.; Mamiro, D.P.; Mtui, H.D.
The objective of this was to evaluate the effect of African weaver ant (Oecophylla longinoda) on fruit fly disease-inflicted postharvest losses of oranges in small-scale farming in Coast region, Tanzania. The treatments consisted of weaver ant population estimated based on the number of nests (0, 2, 5 and 8) of weaver ants per tree and each was replicated three times. Orange fruits were randomly picked from farmers’ orchards at color breaker stage and were immediately transported and placed on benches in a postharvest laboratory at Sokoine University of Agriculture with average temperature of 19 and 28 °C during the night and day, respectively. Data were subjected to analysis of variance using GenStat Statistical Programme 12th Edition and treatment means separation was conducted based on LSD test at P ≤ 5 %. Results indicated that the incidence of fruit fly infection in orange fruits significantly (P < 0.05) decreased from 0.8 to 0.4 % as weaver ant population increased from 0 to at 2 nests per tree and the average number of pupae per fruit decreased from 0.58 to 0.04, respectively. Similarly, orange fruit decays significantly (P < 0.05) decreased from 20.4 to 10.2 % as weaver ant population increased from 0 to 2 nests per tree. Specifically, the incidence of decays due to anthracnose (Colletotrichium gloeosporioides Sacc.) decreased from 11.1 to 7.8 % and that caused by green moulds (Penicillium italicum Wehmer) decreased from 9.3 to 2.4 % as weaver ant population increased from 0 to 2 nests per tree. It is concluded that two nests of weaver ants per tree is an optimal population for substantial reduction of orange postharvest losses caused by fruit fly and fungal infections. The use of weaver ants can find wide applications in organic farming and small-scale orange farming where pesticide application is unaffordable. As the number of weaver ants per nest may differ, further studies are recommended to determine the actual number of weaver ants that can effectively reduce fruit fly and disease-inflicted decays, particularly in small-scale mixed cropping systems.
Molecular improvement of food functional properties of Soybean glycinin by protein engineering
(Tanzania Journal of Agricultural Sciences, 1998) Gidamis, A. B.; Nnko, S. A.; Bunzo, M.; Utsumi, S.; Kito, M.
A study was made to elucidate the three dimensional structure of soybean glydnin which is one of the dominant storage proteins of soybean seeds. Previously, the twodisulphide bonds Cys12-Cys45 and Cys88-Cys298 in the proglydnin AlaBlb subunit were deleted andCys residues were replaced by Gly and Ser by Oligonucleotide-directed mutagenesis. The mutant proglycinins Gly12, and Ser88 showed to have better gelation and emulsifying properties. The mutant proglydnins were crystallised along with the normal proglycinin (AlaBlb -3) and subjected to X-ray structure analysis in an attempt to determine their structure-junction relationships. The crystals diffracted X-ray to a resollttion limit of 2.9 - 3.4A on stillphotographs and belongto the tetragonal system, space group P41 or P43 with cell dimensions of a = b·= 114.3 - 115.2A. and d;= 145.7 - 147.1A with 3 protomers per asymmetric unit. Further refinement data for the' crystals of normal prpglycinin were obtained by multiple isomorphous replacement and solvent flattening techniques. The tri1?ler dimensions of tlie normal proglydnin as determined at 6A were 93A by 93A with·the thickness of 36A.
Comparative evaluation of different methods of extraction and purification used in technical enzyme production from microorganisms
(Tanzania J. Agric. Sc, 1998) Gidamis, A. B.; Nnko, A.; Shayo, N. B.; Chove, B. E.; Kroner, H. K.
A stlldy was conducted to compare the efficiency of two methods of microbial cell separation and enzyme purification using penicillin-G-acylase (PGA) from Escherichia coli. The efficiency of two methods of ceJ[ separation; centrifugation and cross flow filtration (CFF) were compared. The CFF method was found to have both higher separation efficiency and enzyme yield than centrifugation method. Centrifugation method gave a separation efficiency of 98.5% with enzyme yield of94 % whereas CFFmethod resulted in 100% separation efficiency and enzyme yield of98.8%. The Escherichia coli cells were disrupted by high pressure homogenization (HPH),and the disrupted cells were purified using two different techniques. Technique I was a combination of cross-flow-diafiltration (CFD) , ultrafiltration (UF) and heat/pH-shift treatments. This technique resulted in 47% enzyme yield with a purification factor of 12. Technique II which involved two extraction steps by' aqueous two - phase system (APS) coupled with UF resulted in 62 % enzyme yield with a pu;ificationfactor of 4. Technique I was therefore much better than techriique Il in purifying the enzyme. For higher enzyme yield, technique II would seem to be a better one than technique I.
Processing of cassava, residual cyanogens and mycotoxin content in traditionally processed cassava products
(The University of Reading, 1998-04) Muzanila, Yasinta C.
Cassava samples from some villages in Tanzania processed by wet fermentation, solid state fermentation and sun drying were analysed for residual cyanogens and presence of mycotoxins. Cassava samples (bitter varieties) processed by wet and solid- concluded that wet fermentation is very effective in reducing cyanogens in cassava. No mycotoxins (aflatoxins ) were detected in cassava samples. The chemical composition of these cassava samples was also determined. Wet fermentation showed lower content of vitamin C, reducing sugars and protein compared to samples processed by solid state fermentation and sun drying. In another experiment, cassava flakes were produced on a drum drier using varying pre cooking temperatures and drum speeds. Pre-cooking conditions were: no pre-cooking, pre-cooking at 75°C for 35 minutes and 100°C for 5 minutes. The drum speeds used were 11.5 and 14.0 r.p.m. which correspond to 4.0 and 3.4 seconds drying time respectively. The flakes were analysed for vitamin C, moisture, free starch, reducing sugars and protein content. Pre-cooking conditions affected vitamin C, moisture and free starch content while Hmm speed affected only the moisture content of the flakes. Prolonged pre-cooking time caused losses in vitamin C while pre-cooking at the higher temperature increased free starch content of the flakes. The moisture content increased with increasing drum speed. The soluble amylose test showed that starch retrogradation occurs when cassava is cooled after the pre-cooking stage. The textural characteristics of reconstituted mash from the flakes was analysed using the Texture Analyser, after adding emulsifiers (stearate monoglyceride, sodium caseinate and skim milk powder). Results from Texture Profile Analysis (TPA) (adhesiveness), tests showed that stearate monoglyceride Back extrusion and sensory evaluation emulsifier reduces the stickiness of reconstituted cassava flakes mash. The Differential Scanning Calorimetry (DSC) thermograms indicated the formation of an amylose monoglyceride complex. Cassava samples with stearate monoglyceride had low water absorption capacity and high bulk density. Also sample with stearate monoglyceride had low viscosity according to the results from the Brabender amylograph tests. Samples of cassava flakes and reconstituted mash with skim milk powder and sodium caseinate were darker in colour compared to those with stearate monoglyceride according to the results from both instrumental (Hunter Lab spectrophotometer) and sensory tests.
Improvement of the dehulling efficiency of sorghum and millet
(University of Newcastle upon Tyne, 1999-12) Lazaro, Ezra Lyimo
Methods for improvement of the dehulling efficiency of sorghum and millet were investigated. These included: studying the fundamental physical and mechanical properties of the grain and how these properties are influenced by different process variables, the use of different pre treatment methods to loosen the grain seed coat and hence facilitate its removal during the dehulling process, the use of alkali dehulling as an alternative method to conventional abrasive and traditional dehulling methods, development of a numerical model which could be used as a tool for further study of the abrasive dehulling process and finally development of a prototype dehuller combining dehulling principles from both traditional and mechanical dehulling systems which could dehull tempered grain without problems experienced in current mechanical dehullers. The effects of grain and process variables, such as moisture content, temperature and loading conditions on mechanical properties of grain were studied under uniaxial compression of individual whole grain kernels. Five temperature and moisture dependent parameters, which included modulus of deformability, ultimate strain, ultimate stress, energy to break point, force to break point and modulus of toughness were evaluated from force-deformation relations obtained. Each of these parameters except ultimate strain decreased with increase in kernel moisture content and temperature. Grain strength properties also depended heavily on the orientation of the grain during loading (flat loading vs. side loading), indicating that sorghum kernel was anisotropic with respect to mechanical properties. Effect of different pre-treatments on dehulling efficiency was investigated using hydrothermal pre-treatments. These included, treating the grain with steam or tempering with distilled water for different durations followed by drying using either unheated ambient air at 20°C or heated air at 60°C to their initial moisture content (12%db). A tangential abrasive dehuller was used to dehull the pre-treated grain and the effect of different pre-treatments on dehulling efficiency of the pre-treated grain was evaluated based on the extent of seed coat removal and crude fibre reduction in the dehulled grain. Results indicated that hydrothermal pre-treatments improved the dehulling efficiency of sorghum and millet by an average of 8.5% and 20% respectively in terms of seed coat removal and by 16% and 13.7% respectively in terms of crude fibre reduction in the dehulled grain compared to untreated grain. Tempering the grain for a short duration (<15 minutes) reduced the seed coat adhesion in sorghum and millet substantially without affecting the grain strength properties significantly. Seed coat adhesion strength at different tempering durations was quantified by measuring the tangential force required to remove a unit area of seed coat using a friction apparatus. Tempering for 15 minutes reduced the seed coat adhesion strength per unit area by 91.1% and 95.7% compared to untreated grain for sorghum and millet respectively. The effect of seed coat adhesion reduction due to tempering, however, was reversible as the grain kernel was dried. I Alkali dehulling of sorghum and millet was investigated using an aqueous solution of sodium hydroxide as a dehulling agent. Results indicated that alkali concentration, soaking time and temperature were significant factors during the dehulling process. Soaking the grain in 10% aqueous solution of sodium hydroxide for 10 minutes at 60°C was found to be the optimum alkali dehulling conditions for sorghum and millet. Under these conditions 90% yield of unbroken endosperm at 89% dehulling efficiency was achieved from a soft red sorghum variety, which is higher than can be achieved using any of the conventional dehulling systems. Moisture absorption characteristics of sorghum and millet during tempering were studied at different temperatures, initial grain moisture contents, and endosperm textures. Temperature had a significant effect on moisture absorption characteristics of both sorghum and millet, moisture absorption increased with increase in temperature for both sorghum and millet. The moisture absorption characteristic was modelled using Fickian diffusion model and Peleg's model. Peleg’s model was able to simulate the moisture absorption characteristics of both sorghum and millet at initial soaking stages more accurately than the Fickian diffusion model. A general model, based on Peleg’s model and Arrhenius function, was developed for prediction of tempering duration at different temperatures within 20 - 50°C temperature range. The abrasive dehuliing process was successfully modelled using a three-dimensional discrete element model. The computer code was validated by experiment, and good correlation was obtained between simulation and experimental results. Several numerical experiments were also carried out using the developed computer code to investigate the influence of mill and grain parameters on dehulling of sorghum and millet. This model thus provides a tool which can be used to study the dehulling process in more detail than is currently possible using other methods. Based on experimental results from the grain physical and mechanical property and pre treatment tests, a prototype dehuller incorporating a dehuliing surface, which enabled it to dehull moist grain without clogging, was designed and constructed. Grain-grain and grain- dehuller surface friction was the main dehuliing principle. The dehuller was able to achieve higher yield, dehulling efficiency and colour reduction tangential abrasive dehuliing device (TADD).
Estimation of body gain of entire and castrated male pigs at two feeding levels and three body weights, using energy/nitrogen balance and comparative slaughter techniques
(2000) Laswai, G.H.; Close, W. H.; Longland, A.C.
Rates of tissue gain and body composition of 18 entire (E) and 18 castrated (C) male pigs, fed at one of two levels offeeding (high (H) or low (L)), were investigated in a 2x2factorial experiment. Calorimetric, energy and rlitrogen balances were carried out on each animal at 30, 60 and 90 kg live weight. The animals were slaughtered at 95 kg and their body composition was determined. The higher feeding level resulted in greater (P < 0.001) rates of body weight gain, protein andfat deposition in all treatment combinations. Castration was associated with decreased and increased potentialfor protein andfat deposition, respectively. Mean values of shoulder fat thickness, loinfat and subcutaneousfat (P2) were greater (P< 0.01 )for the animalsfed at the high compared with thosefed at the low level and thesefat measurements were greater in the castrated than the entire male pigs. Relative to the slaughter method, the balance method overestimated and underestimated the rates of protein andfat deposition by 0.16 and 0.10, respectively.
Characterisation of Tmmmian Local Sorghmn Varieties
(2000) Laswai, H. S.; Shao, M. R.; Mosha, T. C. E.; Muzanila, Y. C.
Many local varieties of sorghum grown in Tanzania have not been characterised in terms of their end uses. This study was conducted to characterise 14 such varieties. Three improved varieties commonly grown in this country were includedfor comparison. Physical analyses that included 100-grain weight, percent dehulling loss and percent water absorption were done. Chemical analysis of the samples to determine protein, crude fibre, fat, ash, and carbohydrate contents was done. Results showed that the 1 OO-kernel weight ranged between 1.48 and 3. 18 g. Some of the local varieties had kernel sizes that were greater than those of the improved ones. Dehulling losses for the studied varieties ranged from 4.63 to 29.85%. These losses were generally low for the commonly used local varieties. Water absorption ranged between 6.10 and 28.85%. The flour making varieties showed low water absorption capacity. The protein contents of the studied varieties (8.27-13.52%) differed significantly (P<0.05). However, the crudefibre {1.23-2.30%),fat (3.00-4.30%), ash (1.96-4.25%), and carbohydrate contents (78.84-83.96%) ofsorghum varieties did not differ significantly (P>0.05). Studies on endosperm texture revealed that most floury varieties had generally high dehulling losses and were therefore unsuitable for producing dehulled products. Corneous varieties were considered suitable for producing dehulled products due to their low dehulling losses. The intermediate endosperm texture varieties, which also experienced intermediate dehulling losses, need more studies in order to be properly classified Some of these, varieties such as Langalanga are already being used for flour making without prior dehulling. The study, therefore, calls for more screening of the local sorghum varieties not used in this study to identifY their potential in relation to end uses for future exploitation and, where possible, to exploit the promising trait for incorporation in breeding programmes.
Soybean moisture absorption properties and their related size changes by imaging (Part 2) 3D size changes-
(J SASJ, 2000) Urasa, R. L.; Tanaka, S.; Tanaka, F.; Morita, K.
The study was conducted by using 2D image processing technique, actual measurements of three dimensions 'a' , 'b' and 'c' mutually perpendicular axes by vernier caliper and actual volume of grain by picnometer during soaking, with an objective of estimation of volume. The study revealed that; (1) the ratio of instantaneous size to initial size a/a0, b/b0 and c/c0 change with moisture content have a significant disproportion as moisture content increases. (2) The ratio 'b/a' and 'c/a' changes with moisture content have 3 periods: constant, falling, and equilibrium. (3) Shape factor has linear relationship with moisture content, and temperature is insignificant. (4) The product of the sizes 'a', 'b' and 'c', that is volume of the circumscribing rectangular box, closely estimates measured volume of grain based on circumscribed theoretical volume within r2=0.90. (5) Specific volume (abc) and actual specific volume have linear relationship with moisture content, and temperature is insignificant. (6) Actual dry solid density of soybean can be extrapolated from specific volume-moisture content relation, and evaluated as 1.36 (g/cm3). Difference in initial moisture content is insignificant. (7) Image pixels raised to the power of 1.5 modified by shape factor can estimate measured volume within r2=0.90.
Chemical, functional and organoleptic evaluation of african breadfruit (treculia africana Decne) kernel flour for making cookies
(2000) IBadifu, G.I.O.; Akuboil, P.I.; Akpapunam, M.A.
African breadfruit (Treculia africana Decne) seeds were parboiled and their kernels dried and milled into flour. The flour was packed in two different materials and stored under ambient (30 .±... 2°C) conditionsfor 5 months. Chemical,junctional and organoleptic properties oftheflour before and during storage were evaluated. Cookies were made with the flour in addition to wheat flour. Results showed that parboilingfor 15 min did not adversely affect the vitamin C and total carotenoids contents of the kernel. Other nutritional components - protein, oil, ash andfibre of the kernels were not deleteriously affected by parboiling. Within 2 months of storage, 20- 28% vitamin Cand 13-17% and total carotenoids were lost whereas after 5 months, 48-50% and 36744% of vitamin C and carotenoids were lost, respectively. There was significant difference (P< 0.05) between the rate of depletion of vitamin .C and carotenoids. During storage of the flour, apart from its bulk density and swelling index other junctional properties (foam stability, emulation activity, nitrogen solubility) changed irrespective of the packaging material. However, the flour could store for 2 months under ambient (30+ 2°C) conditions without adverse changes in quality. Cookies made from composite
Effects of castration, level of feeding and body weight on Energy partition and efficiency of energy utilisation in growing pigs
(2001) Laswai, G.H.; Close, W.H.; Mtenga, W. H.
Efects of castration, feeding level and body weight on energy partition and efficiency of energy utilisation in growing pigs were studies. Eighteen entire and 18 castrated males, fed on either high (3.34 x maintenance) or low (225 x maintenance) level of feeding in a 2x2 factorial design, with 9 pigs per treatment were used. Energy nitrogen balance and calorimetry were recorded at 30, 60 and 90kg body weight. Increased feeding level resulted into increasing rates of energy (ER), protein energy (Pe) and fat energy (Fe) retention by 0.45, 0.29 and 0.62, respectively. Castration increased ER and Fe by 0.16 and 0.42, respectively but decreased protein energy retention by 0. 13. Energy requirement for maintenance (MEm) was 0. 10 higher in the entire than castrated males and tended w increase with increased protein energy retention. Net energetic efficiences for protein (kp) and fat retention (kj) were higher for the entire (0.61 and 0.98) than for castrated males (0.56 and 0.92) The results indicate that an increase in the rates of energy expenditure with increased lean tissue growth potential may be attributed to increased energy requirement for maintenance.
Proximate composition and mineral content in different, types of traditional TOGWA used in Tanzania as a weaning food
(2001) Ndabikunze, B.K.; Sorhaug, T.; Mtebe, K.I.
Six types of traditional togwa (a traditional fermented gruel prepared from a mixture of malted and unmalted cereal grains), six simulated togwa and their ingredients were analysed for proximate composition, energy and mineral contents. The cereals used were maize (Zea mays), finger millet (Eleusine coracana) and sorghum (Sorghum bicolor). Malt was prepared from sorghum and finger millet. The: concentration of protein in traditional and simulated togwa was higher compared to their main ingredients. The ranges were 9.1-12.5, 9.9-12.9 and 8.7-12.0% respectively. Crude fibre was also higher in traditional and simulated togwa than in the main ingredients, while carbohydrate percent of DM and energy contents were lower than in the ingredients. Ash contents in traditional togwa was 1.44-2.21% and for simulated togwa 1.32-2.2%. Results for mineral contents indicated that phosphorus; magnesium and potassium were the major mineral constituents in both the traditional togwa and laboratory simulated samples. In the traditional and simulated togwa samples, phosphorus content ranged, respectively befween 196-334 and 191-332 (mg/100g), magnesium between 59.5-123.7 and 59.4-123 (mg/100g) and potassium between 167-315 and 167-313 (mg/100g). Calcium range was 3.95-12.32 (mg/100g) in traditional togwa and 3.40-11.92 (mg/100g) in simulated togwa compared to 5.57-14.59 (mg/100g) in the main ingredients. Iron, zinc and copper contents were slightly higher in traditional and in simulated togwa compared to their levels in the main ingredients. Iron ranged between 18.5-23.8 and 18.5-24.8 (mg/100g) in traditional and simulated samples respectively, and zinc ranged between 1.39- 1. 82 (mg/100g) in traditional togwa and 1.41-1.81 (mg/100g) in simulated samples. The contant of coppel in traditional and simulated togwa were 0. 33 - 0.69 and 0.32-0.70 (mg/100g), respectively. Apparently, the choice of cereal and malt and the processes of germination and fermentation for togwa production affects the proportions of nutrients found in the product. This results in different types of togwa with variation in proximate composition, energy density and mineral content.
Emulsifying properties of soy protein isolates obtained by microfiltration
(Society of Chemical Industry, 2002) Chove, B. E.; Grandison, A. S.; Lewis, M. J.
Soy protein isolate (SPI) fractions were produced using two different pore size micro®ltra- tion membranes. Micro®ltration was carried out on SPI produced by isoelectric precipitation of a crude protein extract. Five fractions were obtained: two retentates and two permeates from the two membranes plus an intermediate fraction obtained as the retentate on the small-pore-size membrane using the permeate from the larger-pore-size membrane. Emulsions stabilised by the retentate fractions exhibited higher values (P < 0.01) of emulsion stability index (ESI) and emulsifying activity index (EAI) than those stabilised with fractions made from the permeates. The intermediate fraction gave intermediate ESI values, while the EAI values were not signi®cantly different from those for SPI and one of the retentates. SDS-PAGE pro®les indicated that the fractions exhibiting high functionality in terms of ESI and EAI were also richer in 7S globulin soy protein subunits
Nutritional status and socio-economic problems of adolescent pregnant girls: A case study of Morogoro, Coast and Dar es salaam regions
(Sokoine University of Agriculture, 2002) Shirima, Candida Philip
Adolescence is a distinct and dynamic phase of development and considered to be the period between 10 and 19 years of age. It marks the onset of puberty. In some communities, it means the girl child is ready to engage in marital affairs and bear children. This dissertation presents the results of a study conducted in Temeke, Kibaha and Morogoro districts to examine the socio-economic factors and nutritional problems of adolescent pregnant girls. Specifically, the study examined prevalence of adolescent pregnancies, factors contributing to early pregnancies, problems faced by pregnant adolescent girls, pre-pregnancy nutritional status, nutritional status during pregnancy and pregnancy outcome. Primary data were collected from 180 pregnant adolescent girls and 600 non-pregnant adolescent girls. Nutritional status was assessed by anthropometric and biochemical methods. Statistical Package for Social Sciences (SPSS) was employed to analyse the data. Prevalence of adolescent pregnancy was found to be 21.5% for Temeke district, 19.5% in Kibaha district and 17.7% in Morogoro district. Factors identified to contribute to early pregnancy are: traditions and culture of initiation rites, lack of knowledge on family planning, fear of side effects associated with family planning methods and economic hardship among adolescent girls. It was further observed that adolescent girls encounter many problems such as unplanned pregnancies and marriages, dropout from school, late detection of pregnancy, late antenatal visit to detect any abnormalities, rejection by their partners after conception, and economic dependence.
Improving sweet potato processing and storage performance throug slicing, drying and packaging
(2003) Silayo, V.C.K.; Laswai, H.S.; Makungu, P.J.
Sweet potato is an important food security crop in, many parts of Tanzania. Despite this potential, research into its post-harvest handling for maximum utilisation hass been low. The objective of this study was therefore, to assess slicing performance of a fabricated hand operated slicing machine against the traditional knife slicing by hand in the production of michemhe. It also assessed how slice thickness, the drying surfaces, and packaging of the slices influenced quality during storage. The slicing machine was set to produce slices of 4.8 12 and 16 mm thickness. Together with the traditionally obtained slices the samples were dried on three surfaces (perforated surface, thatched roof and on the ground) for three days. Dry samples were then packaged in polypropylene bags, perforated polyethylene bags and sealed plastic containers and stored for nine months with observation carried in three months intervals. The investigations included moisture content, fungal count and mycotoxin detection discoloration and insect infestation aa quality attributes. Results showed that the slicer throughput ranged between 16 and 46 kg/h of fresh peeled roots in the thickness range of 4-16 mm, against 17 kg/h for traditionally sliced (75 mm) sweet potatoes. During drying, weight of slices decreased exponentially with time. In terms of drying effectiveness, the three drying surfaces used displayed almost the same final mean moisture content in the lower slice thickness range (4-8 mm). With increased slice thickness to 12 and 16 mm: the perforated surface was the most effective (10. 63-18. 03%) followed by the ground floor- (15.67-18.65%) and thatched roof the least (16.5-19.36%) Quality of dried michembe decreased with storage time and the best performance was obtained in polypropylene bags for the nine months storage. Packaging in sealed plastic containers produced the worst results. Quality was also influenced by the drying surfaces used with ground floor resulting in poor product and perforated surface the best. Increasing the slice thickness affected the quality of the dry product except in the range of 4 to 8 mm. Slicing of the roots to 4-8 mm drying on perforated surface and packging in polypropylene bags for room temperature storage of up to six months produced michembe of acceptaple quality. Use of improved slicing machines including mechanically powered machines requires further investigation. Studies on more drying surfaces more packaging materials, and nutrition of michembe are also recommended
Physicochemical properties of curd prepared from melon seeds
(2003) Egbekun, M.K.; Akubor, P.I.
Melon seed was investigated as an alternative to soybeans for production of high protein curd. The coagulating properlies of calcium sulphate and the nature of the curd obtained from melon seeds were investigated. The yield proximate composition and sensory properties of the melon curd were determined. The yield curd from melon seed at 0.54% calcium sulphate concentration was 21% with the protein yield of 33%. Among the concentratiom of calcium sulphate studied 0. 54% appeared to be most suitable for making curd of smooth texture. In general scores for all the sensory attributes evaluated increased with increased calcium sulphate concentration. The melon curd was highly rated and very well accepted.

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