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Publication Indigenous Technical Knowledge and Formulations of Thick (Ugali) and Thin (Uji) Porridges Consumed in Kenya(African Journal of Food Science, 2016-12-31) Wanjala, W. G.; Onyango, A.; Makayoto, M.; Onyango, CThick (ugali) and thin (uji) porridges are important sources of nutrients for millions of Kenyans. They are made from unblended or composite flours of cassava and whole milled maize, finger millet or sorghum. Ugali is eaten as a main meal at lunch or dinner whereas uji is taken as a refreshing drink any time of the day. Uji is also an important complementary food for children. In addition, some formulations of ugali and uji are used to manage non-communicable diseases such as cardiovascular diseases and type II diabetes. The aim of this study was to document indigenous technical knowledge on ugali and uji in Kenya. Primary information was collected through Focus Group Interviews in ten counties in western Kenya and corroborated with secondary literature. Unblended whole milled white maize and finger millet are the preferred flours for making ugali and uji, respectively. Whole milled maize, finger millet and sorghum are recommended for preparing ugali and uji for people suffering from non-communicable diseases. Uji prepared as a complementary food for child-feeding is usually supplemented with plant or animal proteins in order to improve its nutritional quality. The indigenous technical knowledge provided by the interviewees show that several opportunities exist for product innovations and quality and safety improvements.Publication Starch and Modified Starch in Bread Making: A Review(African Journal of Food Science, 2016-12-31) Onyango, CalvinStarch is an important source of energy in human nutrition. It is also widely used as a processing aid in several food and non-food industries. Starch in wheat flour contributes to the development of optimal bread crumb and crust texture. It is also responsible for physical deterioration of bread quality through staling. Starch is mainly extracted from starch-rich plants such as cereals, root and tuber crops and legume seeds. It can be modified using chemical, physical or enzymatic techniques to obtain modified starch. Traditional plant breeding or genetic modification can also be used to produce starches with modified functionalities. Modified starches are essential food processing aids because of their enhanced functional properties. The aim of this paper is to review the role of starch in bread making and subsequently elucidate the influence of modified starch on the quality of wheat bread.Publication Synthesis and In Vitro Digestion of Resistant Starch Type III from Enzymatically Hydrolysed Cassava Starch(International Journal of Food Science & Technology, 2008) Onyango Calvin; Mutungi ChristopherResistant starch type III (RS III) was synthesised from cassava starch by autoclaving followed by debranching with pullulanase, at varied concentrations (0.4–12 U g)1) and times (2–8 h), and recrystallisation ()18 to 90 C for 1–16 h). The highest RS III yield (22 g ⁄ 100 g) was obtained at an enzyme concentration of 4 U g)1 after 8 h incubation, followed by recrystallisation at 25 C for 16 h. Varying the recrystallisation conditions indicated that higher RS III yields (30–35 g ⁄ 100 g) could be obtained at 90 C within 2 h. Thinning cassava starch using a-amylase prior to debranching using pullulanase did not further increase the RS III content. In vitro digestion data showed that whereas 44% RS III was digested after 6 h, the corresponding value for cassava starch was 89%.Publication Nutrient composition, sensory attributes and starch digestibility of cassava porridge modified with hydrothermally-treated finger millet(Science Direct, 2020) Calvin Onyango; Susan Karenya Luvitaa; Guenter Unbehend; Norbert HaaseABSTRACT Cassava (CAS) porridge has low energy density and is a poor source of several nutrients. Its energy density and nutrient composition is normally improved by blending it with other flours. The aim of this study was to determine the effect of hydrothermally-treated (HTT) finger millet on nutrient composition, sensory attributes and starch digestibility of cassava porridge. Composite flour had higher protein, fibre, lipid and mineral content than cassava flour. The high α-amylase activity of HTT finger millet permitted the quantity of CAS-HTT flour to be raised from 9.5% w/v to 19% w/v without altering the free-flowing drinkable consistency of porridge. Partial substitution of CAS with HTT finger millet had no effect on starch digestibility and tannin content but increased the phytate content of CAS-HTT porridge. Hydrothermally-treated finger millet masked the aroma and colour of cassava resulting in dark-coloured CAS-HTT porridge with a bitter taste.Publication Crystallinity, Thermal and Morphological Characteristics of Resistant Starch Type III Produced by Hydrothermal Treatment of Debranched Cassava Starch(Wiley Online Library, 2009-11-25) Mutundi C.; Rost F.; Onyango C.; Henle D.; Rohm H.Cassava starch was debranched using pullulanase and the linear glucans recrystallized by incubation at 60°C or by temperature cycling at 120/60°C, and further subjected to heat-moisture treatment (HMT). Resistant starch (RS III) contents increased from 21.4 g/100 g in the debranched starch (DS) to 67.3 g/100 g in the debranched starch incubated at 60°C (DRS) and 47.8 g/100 g in the debranched starch subjected to temperature cycling (DCS), and further to 84.8 g/100 g and 88.4% g/100 g in HMT-DRS and HMT-DCS, respectively. Total crystallinity varied between 31.4-59.8% and the crystalline type was C in DS and DRS and A in DCS, HMTDRS and HMT-DCS. The melting properties were characterized by broad endotherms, but the exact melting region and enthalpy were dependent on recrystallization method. The main endothermic peaks of DS and DRS occurred at 103.9 and 109.8°C, respectively, whereas DCS exhibited split endotherms at 113.6 and 138.1°C. Heat-moisture treatment broadened the endotherms and increased their enthalpies. Scanning electron micrographs revealed surface topography differences related to size and aggregation of individual crystalline bodies.Publication Effect of Resistant Cassava Starch on Quality Parameters and Sensory Attributes of Yoghurt(Current Research in Nutrition and Food Science, 2017-12-04) Mwizerwa, Herve; Abong’, George Ooko; Okoth, Michael Wandayi; Ongol, Martin Patrick; Onyango, Calvin; Thavarajah, PushparajahResistant starch is known to impart a number of health benefits to consumers. It is therefore desirable to increase the content of resistant starch in popular foods such as yoghurt. The current research investigated the effect of cassava resistant starch synthesized by heat-moisture treatment of starch from I92/0057 cassava variety on physico-chemical properties and sensory attributes of yoghurt. Cassava starch rich in resistant starch was incorporated into yoghurt in the proportions of 0, 0.1%, 0.5% and 1%. Corn starch (0.6%) was used as control. Yoghurt was stored at 4oC for 21 days and the effect of starch modification on resistant starch content, viscosity, syneresis, total solids, acidity, lactic acid bacteria count and sensory properties were determined on weekly basis. Applying cassava starch rich in resistant starch into yoghurt in the proportions of 0.5% and 1% had significantly higher (p≤0.05) resistant starch content of yoghurt reaching 3.40 g/100 g and 5.58 g/100 g on day one and 1.92 g/100 g and 4.47 g/100 g on day 21, respectively. There was a significant correlation (p≤0.05) between resistant starch concentration and the physicochemical properties of yoghurt. Yoghurt treated with 1% resistant starch enriched cassava starch had the highest viscosity during cold storage which was determined as 2721.5 mPa s, mPa s, 2650.0 mPa s and 1034.5 mPa s at day 1, day 7, day 14 and day 21 respectively and it had the least syneresis (22.25%). Addition of cassava starch rich in resistant starch significantly increased (p≤0.05) the total solids content of yoghurt but did not significantly (P>0.05) change the sensory properties of yoghurt. The application of 1% of resistant starch enriched cassava starch as yoghurt thickener produces significant quantity of resistant starch in yoghurt with acceptable sensory and physico-chemical properties.Publication Rheological Properties of Wheat-Maize Dough and Their Relationship with the Quality of Bread Treated with Ascorbic Acid and Malzperle Classic® Bread Improver(African Journal of Food Science, 2015-02-28) Onyang, Calvin; Unbehend, Ljiljana; Unbehend, Guenter; Lindhauer, Meinolf G.The aim of this work was to investigate the effect of ascorbic acid and a commercial bread improver on the physical quality of wheat-maize bread, and establish correlations between the physical properties of the bread and rheological properties of the dough. Wheat flour was substituted with 10, 20 or 30% maize flour and the farinograph and extensograph properties of the dough were evaluated. Farinograph water absorption, dough development time, dough stability and farinograph quality number decreased whereas the degree of softening increased with increasing substitution of wheat flour with maize flour. Extensograph dough energy, resistance to extension, extensibility and maximum resistance decreased with increasing substitution of wheat flour with maize flour. Ascorbic acid and commercial bread improver improved bread specific volume and form ratio; decreased crumb firmness, resilience and chewiness; and increased crumb springiness and cohesiveness. Farinograph water absorption and degree of softening; and extensograph energy, extensibility, maximum resistance and ratio number showed the highest number of significant correlations (P ≤ 0.01 or P ≤ 0.05) with the physical properties of wheat-maize bread.Publication Physical Properties of Dry-Milled Maize Meals and Their Relationship with the Texture of Stiff and Thin Porridge(African Journal of Food Science, 2014-08-31) Onyango, CalvinSelected physical properties of white maize meal, obtained by different dry-milling techniques were evaluated and correlated to the texture of stiff and thin porridge. Sifted or par-cooked maize meals had finer particles than hammer-milled maize meals. Hammer-milled maize meals had lower water absorption indices (17-38%) and higher water solubility indices (WSI, 4-5%) than sifted (41-42 and 2-3%, respectively) or par-cooked (114 and 2%, respectively) maize meals. Sifted or par-cooked maize meals had lower breakdown viscosities (0-19 BU) and higher final viscosities (818-1925 BU) than hammer-milled maize meals (89-173 BU and 530-780 BU, respectively). Stiff porridge prepared from par-cooked maize meal (34% w/v), and thin porridge from dehulled and hammer-milled maize meal (10% w/v) had the firmest textures at 80.93 and 1.28 N, respectively. There was a negative correlation (P < 0.05, r = -1.00) between the WSI and total shearing force of stiff porridge prepared from par-cooked maize meal.Publication Functionalization of sweet potato leaf polyphenols by nanostructured composite β-lactoglobulin particles from molecular level complexations: A review(Food Chemistry, 2022-03-15) Shadrack Isaboke Makori; Tai-Hua Mu; Hong-Nan SunSweet potato leaf polyphenols (SPLPs) have shown potential health benefits in the food and pharmaceutical industries. Nowadays, consumption of SPLPs from animal feeds to foodstuff is becoming a trend worldwide. However, the application of SPLPs is limited by their low bioavailability and stability. β-lactoglobulin (βlg), a highly regarded whey protein, can interact with SPLPs at the molecular level to form reversible or irreversible nanocomplexes (NCs). Consequently, the functional properties and final quality of SPLPs are directly modified. In this review, the composition and structure of SPLPs and βlg, as well as methods of molecular complexation and mechanisms of formation of SPLPsβlgNCs, are revisited. The modified functionalities of SPLPsβlgNCs, especially protein conformational structures, antioxidant activity, solubility, thermal stability, emulsifying, and gelling properties including allergenic potential, digestibility, and practical applications are discussed for SPLPs future development.Publication Modification Of Gluten-Free Sorghum Batter and Bread Using Maize, Potato, Cassava or Rice Starch(LWT - Food Science and Technology, 2011-04) Calvin Onyango; Christopher Mutungi; Günter Unbehend; Meinolf G. LindhauerGluten-free sorghum bread was made from cassava, maize, potato or rice starch and sorghum in the ratios 10:90, 20:80, 30:70, 40:60 and 50:50. The other baking ingredients, on flour-weight-basis, were water (100%), sugar (6.7%), egg white powder (6%), fat (2%), salt (1.7%) and yeast (1.5%). Increasing starch content changed the batters’ consistencies from soft doughs to thin pourable batters. Increasing starch content decreased crumb firmness and chewiness, and increased cohesiveness, springiness and resilience of all breads. Cassava-sorghum and rice-sorghum breads had better crumb properties than maize-sorghum or potato-sorghum breads. Although the crumb properties of all breads declined (i.e. firmness and chewiness increased; cohesiveness, resilience and springiness decreased) on storage, the formulation containing 50% cassava starch retained the best overall texture.Publication Debranched Cassava Starch Crystallinity Determination by Raman Spectroscopy: Correlation of Features in Raman Spectra with X-Ray Diffraction And 13C CP/MAS NMR Spectroscopy(Carbohydrate Polymers, 2012-01-04) Christopher Mutungi; Lars Passauer; Calvin Onyango; Doris Jaros; Harald RohmBecause starch crystallinity influences the physical, mechanical, and technological aspects of numerous starch-based products during production and storage, rapid techniques for its assessment are vital. Samples of different levels of crystallinity were obtained by debranching gelatinized cassava starch, followed by subjection to various hydrothermal treatments. The recrystallized products were further subjected to partial hydrolysis with a mixture of α-amylase and glucoamylase prior to freeze–drying. Crystallinities were determined using X-ray diffraction (XRD) and 13C CP/MAS NMR spectroscopy, and correlated with FT-Raman spectra features. XRD crystallinities ranged between 0 and 58%, and agreed with crystalline-phase fractions (R2 = 0.99) derived from the respective 13C CP/MAS NMR spectra. A strong linear correlation was found between crystallinities and integrated areas of the skeletal mode Raman band at 480 cm−1 (R2 = 0.99). With appropriate calibration, FT-Raman spectroscopy is a promising tool for rapid determination of starch crystallinity.Publication Starch and Modified Starch in Bread Making: A Review(African Journal of Food Science, 2016-09-27) Calvin OnyangoStarch is an important source of energy in human nutrition. It is also widely used as a processing aid in several food and non-food industries. Starch in wheat flour contributes to the development of optimal bread crumb and crust texture. It is also responsible for physical deterioration of bread quality through staling. Starch is mainly extracted from starch-rich plants such as cereals, root and tuber crops and legume seeds. It can be modified using chemical, physical or enzymatic techniques to obtain modified starch. Traditional plant breeding or genetic modification can also be used to produce starches with modified functionalities. Modified starches are essential food processing aids because of their enhanced functional properties. The aim of this paper is to review the role of starch in bread making and subsequently elucidate the influence of modified starch on the quality of wheat bread.Publication Effect of Drying Lactic Acid Bacteria Fermented Uji on Its Pasting Properties and Content of Carboxylic Acids(University of Nairobi Department of Food and Nutrition Technology, 1999-01-01) Onyango, Calvin; Okoth, Michael; Mbugua, SamuelThe effect of fermentation and drying on the pasting properties and carboxylic acids of pure flours of maize, finger millet and cassava and of composite flours of maize-finger millet and cassava-finger millet were studied. The pasting properties were measured between 30°C and 96°C in a Brabender Amylograph while carboxylic acids from the uji slurries were determined on thin layer chromatography plates coated with 0.25 mm silica gel. Irrespective of the treatment given, the cereal flours of maize, finger millet and the composite of maize-finger millet consistently had higher onset and peak gelatinization temperatures than pure cassava or the composite of cassava-finger millet. Also the latter two flours developed higher peak viscosities and disintegrated more rapidly after attaining the peak than either pure maize, finger millet or the composite of maize-finger millet. The higher viscosities of the root flours was also reflected in the higher swelling powers and solubility values at 85°C. Fermentation increased the viscosity of the slurries. The greatest increases were recorded by maize (500BU) and the composite of maizefinger millet (780 BU). Fermentation did not affect gelatinization temperatures except for the maize-finger millet composite whose gelatinization temperature decreased by 10°C. Fermentation and drying resulted in increased viscosity when compared to the non-fermented flours, except for the drum dried cassava-finger millet composite. For all the drum dried flours there was a spontaneous increase in viscosity at 30°C when the Brabender Amylograph was switched on. The drum dried flours absorbed about four times their own weight of water; and since the starch granules were pregelatinized, reconstitution in cold water was difficult, as the flour particles tended to lump together, getting wetted on the surface and inhibiting the penetration of water into the interior. In contrast, sun and cabinet dried flours absorbed about 1.9 times their own weight of water and formed smooth slurries in cold water. Fermentation increased total titratable acidity and fixed acidity of the slurries to about 3.9% and 3.6% respectively, while the pH declined from 5.5 to 3.9. On drying there were no significant changes in (p0.05) from the uji prepared from fermented and nondehydrated slurries.Publication Cellulose Nanofibrils from Sugarcane Bagasse as a Reinforcing Element in Polyvinyl Alcohol Composite Films for Food Packaging(Taylor and Francis, 2022) Otenda Brian Victor; Kareru Patrick Gachoki; Madivoli Edwin Shigwenya; Maina Ernest Gachui; Wanakai Sammy Indire; Wanyonyi Wycliffe ChisutiaDue to a high aspect ratio and enhanced mechanical strength, cellulose nanofibrils can be used as reinforcing elements in biocomposite films. In this study, cellulose nanofibrils were isolated from sugarcane bagasse using TEMPO-mediated oxidation and used to reinforce polyvinyl alcohol (PVA) films. The carboxyl group content, functional groups, crystallinity, thermal properties, and morphology of the nanofibrils were investigated. The influence of TOCNF content on the transmittance, swelling, and tensile strength of PVA-TOCNF films were investigated by varying the TOCNF content of PVA films. The fibrils had a carboxyl content of 12.2 ± 0.6 mg/g CE due to the presence of carboxylic groups, an increased degree of crystallinity, and highly porous nanofibrils with lengths between 150 nm and 600 nm. Incorporation of the isolated fiber on PVA films increased the swelling capacity, tensile strength, and UV absorption but a decrease in the solubility of the composite. An increase in the TOCNF content increased the tensile strength of the films with the highest tensile strength of 6.6 ± 2.2 kPa being observed when the TOCNF content was 30%. The improvement in films properties implies that the films can be used as a packaging material due to enhanced water absorption and light-barrier properties.Publication Immunological Responses to Pneumococcal Conjugate Vaccine and Intestinal Nematodes Infestation in Children(Allan et al., 2017) Allan, Lynda A.; Yole, Dorcas S.; Mbai, Fiona N.Pneumonia is among the leading killer diseases of children under five years in Kenya. The most common bacteriological cause of severe and fatal pneumonia is Streptococcus pneumonia (S. pneumonia). S. pneumoniae is usually carried in the nasopharynx of healthy people, but occasionally leads to invasive pneumococcal diseases (IPDs), such as meningitis, pneumonia, otitis, sinusitis and bacteremia. Annually, World Health Organization (WHO) estimates the occurrence of one and a half million of deaths in children under five years, mainly in poor countries.In Kenya, A 10-valent Pneumococcal Conjugate Vaccine (PCV10) introduction into routine immunization schedule has resulted in reduction of the incidence of Invasive Pneumococcal diseases (IPD). However, there is a need to systematically evaluate the confounding factors that limit vaccine efficacy. A common although often overlooked confounding factor in the PCV10 vaccination efficacy is the presence of gastrointestinal nematode parasites in humans, particularly in children living in slums. Here the intestinal nematodes are prevalent and their effects result in an immuno-compromised state. We review the possibility of concurrent intestinal nematode infestation altering PCV10-induced responses in children and the need to devise efficacious treatment strategies
Publication Exposure assessment to staphylococcus enterotoxins in Nile tilapia supplied through semi-regulated and unregulated value chains(Elsevier Ltd, 2021-01-01) Onjong, Hillary Adawo; Ntuli, Victor; Mwaniki, Mercy; Njage, Patrick Murigu KamauThe objective of this study was to estimate the risk associated with staphylococcal enterotoxin (SE) exposure from the consumption of Nile tilapia supplied through the semi-regulated and unregulated value chains in Kenya. The fish supply chain was modeled from landing to consumption of unprocessed (fresh) and processed (salted and sun-dried, smoked, filleted) fish. Data related to the prevalence of Staphylococcus aureus in fish, taking into account survey information on handling, storage, processing and consumption of Nile tilapia were collected from recently completed studies in Kenya. Other model inputs were complemented with data from published and unpublished literature. A probabilistic exposure model was developed with Monte Carlo simulation in Excel add-in software using @Risk software. The simulated levels of S. aureus in fish after handling and storage of salted and sun-dried and smoked fish ranged between 4 log CFU/g and 9.01 log CFU/g (maximum population density), while in fillet, levels of S. aureus following growth during display at retail shops was between 3.10 log CFU/g (5% percentile) and 9.01 log CFU/g (95% percentile). Estimated SE dose per-serving in fish supplied after processing was significantly higher (p < 0.05) in the unregulated (ranged between 0.000150 ng (5% percentile) and 30.0 ng (95% percentile)) than semi-regulated chain. The model revealed that the factors with the highest impact on dose of SE per-serving were the time taken to sell the fish at street markets under ambient conditions and refrigerated fish fillets at retail shops followed by cross-contamination from fish handlers most. The model simulated a zero risk of exposure to SEs from fish supplied via the semi-regulated and unregulated value chain if cross-contamination from handlers was eliminated. Therefore, this highlighted the need for good hygiene practices during the handling and storage of fish along the value chain. A significant reduction in the risk of exposure to SE in processed fish was noted when shelf-life was reduced to a maximum of 72 h. Although the model can be used in risk assessments of fish supplied under the same scenarios, the current study revealed data gaps that need to be addressed to improve the risk assessment.Publication Evaluation of the Knowledge and Activities of a Local Community in Mwea Endemic with Schistosomiasis(IISTE, 2017) Edward, Okonjo; Dorcas, Yole; Dorington, OgoyiEvaluation of the Knowledge and Activities of a Local Community in Mwea Endemic with SchistosomiasisPublication Prevalence and Phylogenetic Diversity of Pathogenic Fusarium Species in Genotypes of Wheat Seeds in Three Rift Valley Regions, Kenya(Otieno P. Kheseli et al., 2021-01-30) Kheseli, Otieno P.; Susan, Imbahale S.; Sheila, Okoth; Otipa, Miriam; Wafula, Wekesa V.Wheat is a source of nutrients for around 40% world’s population and the second most important cereal crop in Kenya. However, Fusarium head blight (FHB) hinders sustainable sufficient production of the crop, causing both economic and health losses. With the emerging unfavorable climatic changes, effective disease management strategies and adequate seed system are necessary to meet the deficiency. Current information on prevalence of the causative pathogens in varieties of wheat genotypes is a critical prerequisite to such strategies. This study aimed at determining the prevalence of pathogenic Fusarium species in seeds of developed varieties of wheat genotypes in three major wheat-producing regions in Kenya. A total of 260 samples of 18 wheat genotypes from 123 farms were collected. Peptone pentachloronitrobenze agar was used for fungal isolation, while identification of Fusarium spp. was based on the gene encoding translation elongation factor 1-α (tef1-alpha) sequence analysis. Fusarium spp. isolated include Fusarium poae, F. tricinctum, F. heterosporum, F. culmorum, F. equiseti, Fusarium sp., F. verticillioides, and F. oxysporum. There was no significant difference in prevalence of Fusarium spp. pathogens among the three regions studied. Fusarium spp. diversity index for Nakuru was 2.008, Narok was 1.4603, and Uasin Gishu was 1.2337. Wheat produce from farm-saved seeds yielded 66.25% of the isolates, while the produce from certified commercial wheat seeds yielded 33.75% of the isolates. The significant finding of the study is that Fusarium spp. associated with mycotoxins that contaminate the wheat food chain seem to be flourishing in all the sampled wheat seed genotypes from the regions studied. Information on the prevalence and diversity of the pathogens on persistence of the disease in the crop is critical in advancing integrative FHB control measures.Publication Assessment, views and challenges of zinc and iron Fortification of locally milled maize flour sold in Nairobi, Kenya(Moi University, 2020-10) Mutuma, Ireen KathureIntroduction: Low nutrient intake of Zinc and Iron is a global problem affecting the health and social economic wellbeing of world population. There is an advocacy for food fortification as one method of dealing with these two serious micronutrient deficiencies. Kenya has not been left behind. A legal notice of June 2012 made fortification of maize flour with zinc and iron mandatory for all maize millers. Limited studies have been done to evaluate compliance to the Kenyan gazette notice on micronutrient fortification standards for maize flour. Objectives: Assessment of Iron and Zinc concentration in maize flour, consumers views and miller challenges on fortification of locally milled maize flour, sold in Nairobi, Kenya. Methods: A cross sectional survey approach was used. The study was carried out in Nairobi County, Kenya. 35 Samples of fortified maize flour were randomly purchased to give a representative sample. Atomic Absorption Spectrometry was used to analyze amounts of Zinc and Iron in the maize flour samples. 384 consumers were interviewed from Nairobi County. Four maize flour millers and a Kenya Bureau of standards personnel responded to the questionnaire. Zinc and iron levels were compared against recommended fortification standards. Data on consumers was extracted, entered on excel spreadsheet and imported into R statistical software package for analysis. Data is presented in prose, charts, and tables. Results: From the study, of the 35 samples analyzed, overall, 14.29% of the samples met the minimum legal requirement of zinc and iron. The amount of iron ranged between1.08 ppm to 19.02 ppm against a minimum of 15ppm, the amount of zinc ranged from 10.64ppm to 56.25ppm against a minimum of 20ppm. Pearson’s correlation between zinc and iron fortification, was negative at a coefficient of 0.487787. Of the respondents who had knowledge on fortification, 61 % were female. There existed a positive relationship (p-value = 0.0248) between knowledge of fortification and age bracket. Consumers believed fortification improved their health at 66%. Major reasons given for fortification non-compliance were corruption and cost at 40% and 30% respectively. Although the media played a major role in creating fortification awareness at 41 %, 62.9% of respondents were not aware of the mandatory maize flour fortification with Iron and Zinc. Of the four millers interviewed, it was clear, there are no government incentives to support the mandatory fortification. Conclusion: The study showed that Maize flour available for public consumption in Nairobi County is not adequately fortified. Consumer knowledge on mandatory fortification to be increased. Millers are not adequately prepared to fortify maize flour adequately. Recommendations: The fortification process to be integrated into the overall food safety mechanisms to ensure conscious and constant monitoring during production. Consumer awareness to be created on the benefits of consuming fortified foods. The government to routinely publish the list of products that are complying and taking disciplinary actions on milers who do not comply. Government incentives such as subsidized costs of laboratory analysis would ensure increased monitoringPublication Effects of social network factors on information acquisition and adoption of improved groundnut varieties: the case of Uganda and Kenya(Springer Science and Business, 2014) Thuo, Mary; Bell, Alexandra A.; Bravo-Ureta, Boris E.; Lachaud, Miche´e A.; Okello, David K.; Okoko, Evelyn Nasambu; Kidula, Nelson L.; Deom, Carl M.; Puppala, NaveenSocial networks play a significant role in learning and thus in farmers’ adoption of new agricultural technologies. This study examined the effects of social network factors on information acquisition and adoption of new seed varieties among groundnut farmers in Uganda and Kenya. The data were generated through face-to-face interviews from a random sample of 461 farmers, 232 in Uganda and 229 in Kenya. To assess these effects two alternative econometric models were used: a seemingly unrelated bivariate probit (SUBP) model and a recursive bivariate probit (RBP) model. The statistical evaluation of the SUBP shows that information acquisition and adoption decisions are interrelated while tests for the RBP do not support this latter model. Therefore, the analysis is based on the results obtained from the SUBP. These results reveal that social network factors, particularly weak ties with external support (e.g., researchers, extension agents, etc.), partially influence information acquisition, but do not influence adoption. In Uganda, external support, gender, farm size, and geographic location have an impact on information acquisition. In Kenya, external support and geographic location also have an impact on information acquisition. With regard to adoption, gender, household size, and geographic location play the most important roles for Ugandan farmers, while in Kenya information from external sources, education, and farm size affect adoption choice. The study provides insight on the importance of external weak ties in groundnut farming, and a need to understand regional differences along gender lines while developing agricultural strategies. This study further illustrates the importance of farmer participation in applied technology research and the impact of social interactions among farmers and external agents.