School‐age children frequently consume snacks. However, most of the snacks they consume are of lo... more School‐age children frequently consume snacks. However, most of the snacks they consume are of low nutritional quality. The objective of this study was to develop a nutrient‐rich and acceptable extruded bean‐based snack, which could contribute to improved nutrient intake, especially for school‐age children. Snack formulations developed from Roba1 beans, maize, orange‐fleshed sweet potato, and amaranth mixtures, and processed in a twin‐screw extruder, were evaluated and optimized for nutritional, textural and sensory properties. High proportion of beans in the formulation was associated with high protein, iron, zinc, and dietary fiber content. An optimal formulation (82.03:10: 5:2.97; beans, maize, OFSP, amaranth), containing 20.38 g, 4.12 g, 4.83 mg, and 1.51 mg per 100 g, of protein, dietary fiber, iron, and zinc, respectively, was obtained. The snacks were crunchy and moderately acceptable with average sensory scores of 6 on a 9‐point hedonic scale, and hardness 26.6 N. Nutrient c...
African eggplant (Solanum anguivi Lam.) fruits reportedly exhibit antidiabetic properties, possib... more African eggplant (Solanum anguivi Lam.) fruits reportedly exhibit antidiabetic properties, possibly due to the presence of bioactive compounds. This study aimed to assess the bioactive compounds content (BCC) and antioxidant activity (AA) in the fruits of fourteen African eggplant accessions. The relationship between the fruit BCC and AA, and the plant (leaf, stem and fruit) morphological characteristics was determined. Morphological traits for the plant accessions were characterized based on existing Solanum species descriptors. Total phenolics, flavonoids, saponins, vitamin C and AA were determined by spectrophotometry, while total alkaloids were detected by gravimetry. HPLC was used for the quantification of phenolic compounds. Morphological characteristics, BCC and AA differed among the accessions. The fruit's accessions contained total phenolics (8.0-12.4 mg gallic acid equivalent/g dry weight (DW)), saponins (51.1-124.8 mg diosgenin equivalent/g DW), alkaloids (81.4-127.7 ...
Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder of glucose homeostasis associated... more Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder of glucose homeostasis associated with a status of insulin resistance, impaired insulin signaling, β-cell dysfunction, impaired glucose and lipid metabolism, sub-clinical inflammation, and increased oxidative stress. Consuming fruits and vegetables rich in phytochemicals with potential antidiabetic effects may prevent T2DM and/or support a conservative T2DM treatment while being safer and more affordable for people from low-income countries. Solanum anguivi Lam. fruits (SALF) have been suggested to exhibit antidiabetic properties, potentially due to the presence of various phytochemicals, including saponins, phenolics, alkaloids, ascorbic acid, and flavonoids. For the saponin fraction, antidiabetic effects have already been reported. However, it remains unclear whether this is also true for the other phytochemicals present in SALF. This review article covers information on glucose homeostasis, T2DM pathogenesis, and als...
International Journal of Agricultural and Biological Engineering, 2016
In this study, an integrated approach incorporating Remote Sensing (RS), Geographical Information... more In this study, an integrated approach incorporating Remote Sensing (RS), Geographical Information System (GIS), local meteorological weather stations’ data and NASA’s virtual meteorological stations’ data were used to quantify Grain Amaranth (GA) water requirements in Uganda. Penman-Monieth method within CropWAT8 model and Surface Energy Balance Algorithm for Land (SEBAL) Model was used to quantify the evapotranspiration. Normalized Difference Vegetation Index (NDVI), daily spatial distribution of Evapotranspiration (ET), Land Surface Temperature (LST) and surface albedo were extracted from satellite imagery. The ratio of effective rainfall (Pe) to Potential Evapotranspiration (PET) – (Pe/PET) and time series for NDVI were computed to determine the growth stage of GA in different areas. The GA water demand was the highest in Karamoja sub-region (467.5 mm/season) and the lowest in Tororo (174.1 mm/season). The growing season for GA in most areas of Uganda was from March to December. ...
This project undertook a survey in Rachuonyo (Kenya), Bukoba (Tanzania) and Rakai (Uganda) distri... more This project undertook a survey in Rachuonyo (Kenya), Bukoba (Tanzania) and Rakai (Uganda) districts to assess the contribution of banana to the household food security and nutrition of PLWHA and assessed the potential nutritional benefit of providing nutrient enhanced banana to PLWHA. Data were collected through interviews with 373 PLWHA and key informants (local agricultural support staff and personnel from PLWHA support agencies) and using focus group discussions. A banana based nutrient enhanced food supplement made by blending banana flour (61%) with soybean flour (39%) and multi?.nutrient fortificant pre?.mix (0.2% of mixture) was distributed to 15 respondents and their nutrient intake estimated. The majority (71.5%) of the survey respondents were females aged 20-50 years; most had no higher than primary level education and the majority were small scale farmers (with gardens <1 acre). Most of the respondents produced and consumed bananas. The study population was generally foo...
Journal of Engineering, Design and Technology, 2021
Purpose Refractance window drying (RWD) has been identified as the method that can give high-qual... more Purpose Refractance window drying (RWD) has been identified as the method that can give high-quality products at a relatively low production cost. However, knowledge about its use and adoption remains lacking both in academic curricula and industry in the developing world. Design/methodology/approach A lab-scale batch RWD of a closed-loop control system was designed, fabricated and evaluated for drying rates, evaporation rate, the energy of evaporation, energy efficiency and throughput. Testing was done using mango and tomato pulps. Findings Drying rates at 95°C of 1.32 gg−1min−1 and 0.854 gg−1min−1 at 2 and 3 mm, respectively, for tomato, 0.6 gg−1min−1 and 0.33 gg−1min−1 at 2 and 3 mm for mango pulp were obtained. The dryer had an evaporation rate of 4.63 × 10–4 kg/s and 4.25 × 10–4 kg/s, the energy of evaporation of 1.05 kW and 0.96 kW and thermal energy efficiency of 25.64% and 21.73% while drying tomato and mango pulps, respectively. Dryer throughput of 0.6 kg/h of dried mango P...
The study was designed to optimize extrusion processing conditions for production of instant grai... more The study was designed to optimize extrusion processing conditions for production of instant grain amaranth flour for complementary feeding. Multi‐response criteria using response surface methodology and desirability function analysis were employed during the study. The central composite rotatable design (CCRD) was used to determine the level of processing variables and to generate the experimental runs. The process parameters tested included extrusion temperature (110–158°C), screw speed (40–52 Hz), and feed moisture content (11%–16%), while response variable was protein digestibility, sensory acceptability, water absorption index, water solubility index, bulk density, and viscosity. Data obtained from extrusion were analyzed using response surface methodology. Data were fitted to a second‐order polynomial model, and the dependent variables expressed as a function of the independent variables. Analysis of variance (ANOVA) revealed that extrusion parameters had significant linear, q...
Tamarind seeds are not consumed despite their high antioxidative activity. In this study, 0–10% t... more Tamarind seeds are not consumed despite their high antioxidative activity. In this study, 0–10% tamarind seed powder (TSP) was incorporated into mango juice and cookies. Total phenolics (Folin–Ciocalteu assay), antioxidant activity (2,2‐diphenyl‐1 picrylhydrazyl (DPPH) radical scavenging assay), flavonoid (aluminum chloride assay), condensed tannins content (Vanillin‐HCl assay), and consumer acceptability (n = 50) of the products were determined. TSP increased the pH and viscosity and reduced titratable acidity of juice. Incorporation of TSP increased the: total phenolic content (6.84 ± 0.21 to 88.44 ± 0.8 mg GAE/100 mL); flavonoid (4.64 ± 0.03–21.7 ± 0.36 mg CE/100 mL); condensed tannins (0.24 ± 0.01–21.81 ± 0.08 mg CE/100 mL) and total antioxidant activity (4.65 ± 0.88–21.70 ± 0.03 mg VCE/100 mL) of juice. A similar trend was observed for cookies. Maximum sensorially acceptable TSP levels were 1.5% and 6%, respectively, for juice and cookies. TSP can thus be utilized as a source o...
School‐age children frequently consume snacks. However, most of the snacks they consume are of lo... more School‐age children frequently consume snacks. However, most of the snacks they consume are of low nutritional quality. The objective of this study was to develop a nutrient‐rich and acceptable extruded bean‐based snack, which could contribute to improved nutrient intake, especially for school‐age children. Snack formulations developed from Roba1 beans, maize, orange‐fleshed sweet potato, and amaranth mixtures, and processed in a twin‐screw extruder, were evaluated and optimized for nutritional, textural and sensory properties. High proportion of beans in the formulation was associated with high protein, iron, zinc, and dietary fiber content. An optimal formulation (82.03:10: 5:2.97; beans, maize, OFSP, amaranth), containing 20.38 g, 4.12 g, 4.83 mg, and 1.51 mg per 100 g, of protein, dietary fiber, iron, and zinc, respectively, was obtained. The snacks were crunchy and moderately acceptable with average sensory scores of 6 on a 9‐point hedonic scale, and hardness 26.6 N. Nutrient c...
African eggplant (Solanum anguivi Lam.) fruits reportedly exhibit antidiabetic properties, possib... more African eggplant (Solanum anguivi Lam.) fruits reportedly exhibit antidiabetic properties, possibly due to the presence of bioactive compounds. This study aimed to assess the bioactive compounds content (BCC) and antioxidant activity (AA) in the fruits of fourteen African eggplant accessions. The relationship between the fruit BCC and AA, and the plant (leaf, stem and fruit) morphological characteristics was determined. Morphological traits for the plant accessions were characterized based on existing Solanum species descriptors. Total phenolics, flavonoids, saponins, vitamin C and AA were determined by spectrophotometry, while total alkaloids were detected by gravimetry. HPLC was used for the quantification of phenolic compounds. Morphological characteristics, BCC and AA differed among the accessions. The fruit's accessions contained total phenolics (8.0-12.4 mg gallic acid equivalent/g dry weight (DW)), saponins (51.1-124.8 mg diosgenin equivalent/g DW), alkaloids (81.4-127.7 ...
Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder of glucose homeostasis associated... more Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder of glucose homeostasis associated with a status of insulin resistance, impaired insulin signaling, β-cell dysfunction, impaired glucose and lipid metabolism, sub-clinical inflammation, and increased oxidative stress. Consuming fruits and vegetables rich in phytochemicals with potential antidiabetic effects may prevent T2DM and/or support a conservative T2DM treatment while being safer and more affordable for people from low-income countries. Solanum anguivi Lam. fruits (SALF) have been suggested to exhibit antidiabetic properties, potentially due to the presence of various phytochemicals, including saponins, phenolics, alkaloids, ascorbic acid, and flavonoids. For the saponin fraction, antidiabetic effects have already been reported. However, it remains unclear whether this is also true for the other phytochemicals present in SALF. This review article covers information on glucose homeostasis, T2DM pathogenesis, and als...
International Journal of Agricultural and Biological Engineering, 2016
In this study, an integrated approach incorporating Remote Sensing (RS), Geographical Information... more In this study, an integrated approach incorporating Remote Sensing (RS), Geographical Information System (GIS), local meteorological weather stations’ data and NASA’s virtual meteorological stations’ data were used to quantify Grain Amaranth (GA) water requirements in Uganda. Penman-Monieth method within CropWAT8 model and Surface Energy Balance Algorithm for Land (SEBAL) Model was used to quantify the evapotranspiration. Normalized Difference Vegetation Index (NDVI), daily spatial distribution of Evapotranspiration (ET), Land Surface Temperature (LST) and surface albedo were extracted from satellite imagery. The ratio of effective rainfall (Pe) to Potential Evapotranspiration (PET) – (Pe/PET) and time series for NDVI were computed to determine the growth stage of GA in different areas. The GA water demand was the highest in Karamoja sub-region (467.5 mm/season) and the lowest in Tororo (174.1 mm/season). The growing season for GA in most areas of Uganda was from March to December. ...
This project undertook a survey in Rachuonyo (Kenya), Bukoba (Tanzania) and Rakai (Uganda) distri... more This project undertook a survey in Rachuonyo (Kenya), Bukoba (Tanzania) and Rakai (Uganda) districts to assess the contribution of banana to the household food security and nutrition of PLWHA and assessed the potential nutritional benefit of providing nutrient enhanced banana to PLWHA. Data were collected through interviews with 373 PLWHA and key informants (local agricultural support staff and personnel from PLWHA support agencies) and using focus group discussions. A banana based nutrient enhanced food supplement made by blending banana flour (61%) with soybean flour (39%) and multi?.nutrient fortificant pre?.mix (0.2% of mixture) was distributed to 15 respondents and their nutrient intake estimated. The majority (71.5%) of the survey respondents were females aged 20-50 years; most had no higher than primary level education and the majority were small scale farmers (with gardens <1 acre). Most of the respondents produced and consumed bananas. The study population was generally foo...
Journal of Engineering, Design and Technology, 2021
Purpose Refractance window drying (RWD) has been identified as the method that can give high-qual... more Purpose Refractance window drying (RWD) has been identified as the method that can give high-quality products at a relatively low production cost. However, knowledge about its use and adoption remains lacking both in academic curricula and industry in the developing world. Design/methodology/approach A lab-scale batch RWD of a closed-loop control system was designed, fabricated and evaluated for drying rates, evaporation rate, the energy of evaporation, energy efficiency and throughput. Testing was done using mango and tomato pulps. Findings Drying rates at 95°C of 1.32 gg−1min−1 and 0.854 gg−1min−1 at 2 and 3 mm, respectively, for tomato, 0.6 gg−1min−1 and 0.33 gg−1min−1 at 2 and 3 mm for mango pulp were obtained. The dryer had an evaporation rate of 4.63 × 10–4 kg/s and 4.25 × 10–4 kg/s, the energy of evaporation of 1.05 kW and 0.96 kW and thermal energy efficiency of 25.64% and 21.73% while drying tomato and mango pulps, respectively. Dryer throughput of 0.6 kg/h of dried mango P...
The study was designed to optimize extrusion processing conditions for production of instant grai... more The study was designed to optimize extrusion processing conditions for production of instant grain amaranth flour for complementary feeding. Multi‐response criteria using response surface methodology and desirability function analysis were employed during the study. The central composite rotatable design (CCRD) was used to determine the level of processing variables and to generate the experimental runs. The process parameters tested included extrusion temperature (110–158°C), screw speed (40–52 Hz), and feed moisture content (11%–16%), while response variable was protein digestibility, sensory acceptability, water absorption index, water solubility index, bulk density, and viscosity. Data obtained from extrusion were analyzed using response surface methodology. Data were fitted to a second‐order polynomial model, and the dependent variables expressed as a function of the independent variables. Analysis of variance (ANOVA) revealed that extrusion parameters had significant linear, q...
Tamarind seeds are not consumed despite their high antioxidative activity. In this study, 0–10% t... more Tamarind seeds are not consumed despite their high antioxidative activity. In this study, 0–10% tamarind seed powder (TSP) was incorporated into mango juice and cookies. Total phenolics (Folin–Ciocalteu assay), antioxidant activity (2,2‐diphenyl‐1 picrylhydrazyl (DPPH) radical scavenging assay), flavonoid (aluminum chloride assay), condensed tannins content (Vanillin‐HCl assay), and consumer acceptability (n = 50) of the products were determined. TSP increased the pH and viscosity and reduced titratable acidity of juice. Incorporation of TSP increased the: total phenolic content (6.84 ± 0.21 to 88.44 ± 0.8 mg GAE/100 mL); flavonoid (4.64 ± 0.03–21.7 ± 0.36 mg CE/100 mL); condensed tannins (0.24 ± 0.01–21.81 ± 0.08 mg CE/100 mL) and total antioxidant activity (4.65 ± 0.88–21.70 ± 0.03 mg VCE/100 mL) of juice. A similar trend was observed for cookies. Maximum sensorially acceptable TSP levels were 1.5% and 6%, respectively, for juice and cookies. TSP can thus be utilized as a source o...
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