Articles, Conference and Workshop Papers Collection

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    Development of natural liquid and powdered meat tenderizer based on papaya peel, ginger and garlic
    (Science Publishing Group, 2024-04-12) Issa-Zacharia Abdulsudi; Muhimbula Happiness Samuel; Bikuba Anastazia Niyonkulu; Mato Joachim Dotto
    Recently, the application of exogenous enzymes for meat tenderization has turned the attention of food technologists and meat scientists. This research investigates the synergistic impact of natural tenderizers derived from the combination of papaya peels (P), ginger (G), and garlic (Ga) on the sensory attributes of goat meat such as color, aroma, taste, tenderness and overall acceptability. The tenderizers were formulated in different concentration ratios of 3:2:1 in both liquid and powdered form. The sensory quality parameters for all tenderized goat meat samples under observation including the control, were evaluated by 60 semi-trained panelists using a five-point hedonic scale. The effect of tenderizers was compared to the control which was devoid of tenderizing ingredients. Tenderness was greatly improved (p<0.05) by tenderizer P:G:Ga (3:2:1) in both liquid and powder forms at 45- and 90- minutes of tenderization. Alternatively, liquid and powdered Ga:G:P (3:2:1) were highly significantly rated (p<0.05) in taste compared to all other tenderizer formulations for 45- and 90-minute tenderization. From the samples tested, the control sample in both setups was the least rated in all sensory attributes, except for color in powdered tenderization. Generally, liquid and powdered P:G:Ga (3:2:1) and Ga:P:G (3:2:1) tenderizers received significantly higher (p<0.05) overall acceptability scores than G:G:aP (3:2:1) and the control sample. While liquid tenderizers mostly performed better compared to powdered tenderizers for all sample combinations, there was a significant improvement (p<0.05) in tenderness when both liquid and powdered tenderizers were used for 90 minutes compared to 45-minute marination. This suggests that, the longer the tenderization time, the greater the effect on tenderness. These findings underscore the importance of natural tenderizers in enhancing consumer satisfaction with meat products,
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    Assessment of compliance with good agricultural practices in pig farming in Mpwapwa and Mbulu districts, Tanzania
    (Taylor & Francis Group, 2023-07-14) Nonga, Cosmas; Zacharia, Issa; Mkupasi, Ernatus; Ngowi, Helena
    A cross-sectional study was conducted between February and May 2022 to explore the pig farming practices and assess their compliance with Good Agricultural Practices (GAPs) and their associated constraints in Mpwapwa and Mbulu districts. A total of 136 pig farmers were randomly chosen from purposively selected wards for interview using a structured questionnaire. The study revealed that 71.3% of all pig farmers were aware of GAPs on pig farming, but only 19.8% of the pig farmers complied with the stipulated GAPs. About 81.6% of the respondents had poor piggery hygiene and 76.5% had poor piggery conditions. Pig farmers reported the cost of feeds (83.8%) and veterinary services (81.6%) to be the hindrance to compliance with GAPs. It was concluded that pig farmers are aware of GAPs but not all implement them. Limited availability and high costs of pig feeds and veterinary services are among the factors limiting the full implemantation of GAP in pig farming in the Mpwapwa and Mbulu districts. Therefore, there is a need for the Ministry of Livestock and Fisheries Development and private investors to collaborate to ensure accessibility to Agro-vet services in rural areas with minimal cost. A positive effect could also result from encouraging pig farmers to use locally available ingredients to compose pig feeds.
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    Erosion hazard assessment in the upper Ewaso Ng’iro basin of Kenya: application of gis, usle and eurosem
    (Sokoine University of Agriculture, 1999) Mati Bancy Mbura
    A methodology was developed for assessing soil erosion hazard in the Upper Ewaso Ng’iro basin of Kenya, using Geographic Information Systems (GIS), the Universal Soil Loss Equation (USLE) and the European Soil Erosion Model (EUROSEM). The USLE was used in a GIS environment by creating thematic maps of R, K, L, S, C and P and then calculating soil loss by raster-grid modelling with Arc/Info GRID. The rainfall erosivity factor (R) was derived from relationships between rainfall amount and erosivity using erosion plot data from within the catchment. The nature of the relationship was found to be a function of agi o-climatic zones of the region. Mean annual erosivities ranged from 145 to 990 J m'2 hr'1. For a given amount of rainfall, erosivity was higher in zone IV than in the wetter zones 11-111. The soil erodibility factor (K) was estimated using the USLE nomograph and data from laboratory analysis of field samples collected from representative major soil mapping units. The K-values were low to medium, ranging from 0.10 to 0.25 over 84 percent of the basin. The topographic factor (LS) was obtained by creating Digital Elevation Models (DEMs) of the basin with TOPOGRIDTOOL of Arc/Info. These were then used to determine the slope steepness and length factor values, calculated with raster-grid modelling. Although DEMs proved a useful tool, maximum values of both steepness and length had to be set in this reconnaissance study to achieve reasonable results. A finer resolution of input data and a smaller grid cell size are needed for accurate determination. The cover and management factors (C) were obtained by determining the land cover types within the basin using remotely sensed data (SPOT 1 colour composite prints) and ground truthing studies. The factor values were estimated from USLE guide tables and measurements of cover from plots and test sites. Some 70 percent of the basin is covered by rangelands. The conservation practice (P) factor values were estimated from USLE guide tables and then applied to areas where soil conservation had been introduced /?. M. Mali PM > Thesis 1999 Silsoe College Cranfield .■Ihstract •'university II according to maps obtained from the Ministry of Agriculture. The USLE was validated using data from erosion plots. A value of R2 = 0.645 was obtained between predicted and measured values but the standard error was rather high (e = 5.745 t ha'1 yr'1). Using an annual soil loss of 9.0 t ha'1 yr'1 as tolerance level, some 36 percent of the basin was found to experience unacceptably high erosion rates. Most of this area was communal grazing land and cropland where soil conservation measures had not been applied. A critical land cover type within the grazing land is shrubland, where vegetation cover is less than 40 percent and high erosion risk was predicted and confirmed by field surveys. EUROSEM could not be integrated within a GIS in the time available for research. It was therefore simulated outside GIS environment, where it was applied to Embori and Mukogodo plot data using separate data sets for calibration and validation. Calibration was used to obtain input parameters for saturated hydraulic conductivity, cohesion and Manning’s roughness coefficients. Validation gave correlation coefficients of 0.907 and 0.840 for predictions of storm runoff and soil loss respectively at Embori; the corresponding values for bare soil plots at Mukogodo were 0.895 and 0.577. However, EUROSEM predicted runoff poorly (R2 = 0.570) and failed to predict soil loss at all the vegetated plots at Mukogodo. The model was applied to simulated vegetation covers of barley, maize, grass and forest for a 36.7 mm rainstorm at Embori. The simulated soil losses showed an exponential decrease with increasing cover. At a threshold cover of 70 percent, soil loss diminished to zero under grass and forest and decreased to a minimum value under barley and maize. These results support the USLE simulations, which showed that areas with more than 70 percent cover (such as forest) had a low erosion hazard, even with steep slopes and high rainfall erosivities. This research has demonstrated that GIS can be used with the USLE to assess and quantify erosion hazard, giving results that can be used for conservation planning. EUROSEM can be applied successfully to bare soil and cropland, but application to other land covers requires further investigation. Land cover and topography are the main factors controlling the spatial distribution of soil loss in the Upper Ewaso Ng’iro basin. Future conservation activities should be concentrated on the rangelands.
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    The impacts of frozen storage and fatty acid oxidation on silver carp myofibrillar protein functionality
    (Jiangnan University, Wuxi, JiangsuProvince, P.R., 2006) Mlyuka, Erasto
    Silver carp (Hypophthalmichthys molitrix) is a freshwater species living in temperate conditions (6-28 °C) and its natural distribution is in Asia. It is generally cultured and marketed locally alive or fresh in most of the producing countries. China is the largest producer of silver carp in the world; however, its market price is relatively low compared to most other species, normally costs 8-10Yuan/kg. In order to keep the product longer and further extend the markets instead ofjust consuming it fresh, processing technologies for adding value and frozen storage are of significantly important for this fish species. In this thesis, the report is mainly focused on the study done on isolation of myofibrillar protein from silver carp; exposing the isolated myofibrillar protein to oxidative environment simulated using an iron oxidation model system to mimic the oxidative stress during processing and frozen storage. Also the impacts of the iron oxidation model system, fatty acid oxidation and frozen storage on protein functionality of silver carp myofibrillar protein isolate were evaluated. Oxidative damage to silver carp myofibrillar proteins isolate (MPI) was investigated by measuring changes in physico-chemical, and functional properties after exposure to iron-catalyzed oxidation system (IOS). Iron oxidized MPI exhibited an increase in carbonyl content and dityrosine, which were significant and negatively correlated with protein solubility (PS) (r=0.85), (r=0.80) and gel strength (GS) (r=0.95), (0.93), respectively, however the decrease in total thiol group content was significantly and positively correlated with PS (r=0.77) and GS (r=0.89). These led to significant changes (P<0.05) observed in the protein and functional properties of oxidized MPI. Sodium dodecyl sulfatepolyacrylamide gel electrophoresis demonstrated that IOS resulted in a major loss of myosin and actin associated with formation of protein polymers as supported by gel-permeation chromatography (GPC) results. The total fat content of silver carp MPI was 0.6%, it is mainly composed of unsaturated fatty acids of which about 34% constituted by eicosapentaenoic acid, ( 2O:5co-3), docosahexaenoic acid, ( 22:6co-3), and linolenic, ( 18: 3m-3) as the main co-3 poly-unsaturated fatty acids (PUFAs) as well as linoleic acid, (18:2co-6) and arachidonic acid, (20:4co-6), the main co- 6 PUFAs in fish , unfortunately PUFAs are prone to oxidation producing reactive oxygen species capable of modifying protein structure. This study suggests that the decreased functionality of proteins in muscle foods exposed to an oxidative environment could be due to chemical and physical changes resulting from oxidation reactions. It was found that silver carp myofibrillar protein is susceptible to an iron-catalyzed oxidation causing a significant loss of its functionality, thus a study was carried out to iii Jianenan University, M.Sc Thesis, 2010 Abstract determine the susceptibility of silver carp protein to natural oxidants (fatty acids or fatty acids oxidation products) in frozen storage with respect to its functionality. Frozen stored myofibrillar protein isolate with 0.6M NaCl or myofibrillar protein isolated from previous frozen stored whole fish and fish mince of silver carp at -18°C for 90 days were assessed for protein and lipid oxidation with regard to protein functionality. The addition of sodium chloride to 0.6M at pH6.5 improved protein functionality especially water holding capacity of frozen stored myofibrillar protein isolate from 5.3 to 6.4mL/g MP1 after 90 days of frozen storage. However, the differential scanning calorimeter results showed that, sodium chloride significantly increased thermal susceptibility of myosin from 48.12 to 46.40°C with 0.1M NaCl and 0.6M NaCl frozen stored for 90 days, respectively. Whole fish frozen storage was more susceptible to oxidation compared to fish mince and myofibrillar protein isolate due to their different lipid content. On contrary, myofibrillar isolated from frozen whole fish showed significant changes in protein functionality may be due to great loss of amino acid such as cysteine, lysine, histidine and methionine during frozen storage. On the other hand investigation was done on stabilization and oxidation protection of silver carp MP1 stored at -18 °C, 90 days and composed of MPI, 8% cryoprotectants (4% sucrose and 4% sorbitol) with or without antioxidants (0.2% ascorbate, 0.2% a- tocopherol, or their combination) and packed in a polyethylene bag, sealed under air. MPI without cryoprotectants and antioxidants was the control. Compared with the control, cryoprotectants increased PS (protein solubility), WHC (water holding capacity), OHC (oil holding capacity), EC (emulsification capacity) and GS (gel strength), also, the cryoprotectants and/or antioxidants decreased MPI oxidation susceptibility as well as susceptibility of myosin to thermal denaturation. After 30 days of frozen storage, there were no significant differences ((P>0.05) of storage time on alteration of protein functionality and actin susceptibility to thermal denaturation between cryoprotectants and the control. Antioxidants minimized oxidation effects on MPI frozen storage. Therefore, the present study reveals that, improvement in the functional properties of silver carp MPI were greatly influenced by cryoprotectants and antioxidants, this reflect a great role played by sucrose/ sorbitol and antioxidants in protecting native protein structure to a greater extent owing to impact of frozen storage and oxidation respectively.
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    Influence of botanic and geographic origin on quality of honey from Tanzania.
    (Sokoine University of Agriculture., 2016) Shekilango, Salama Ghuio
    In aview of the expanding global market, characterization of floral and geographic origins of honey has become a more important issue than ever. In general, prices of honey at the international market are set according to floral and geographic origin of the nectar, which relate to the chemical composition. This study was conducted to assess and characterize Tanzania honey from different floral origins and geographic zones based on physicochemical properties and minerals content, sugar profile, total phenol and antioxidant activities as well as sensory properties and consumer acceptability. Samples from two floral origins, Miombo and Acacia were collected from five different zones in Tanzania namely Central. Coastal. Lake. Northern and Southern zones and subjected to chemical and sensory analyses. Complete randomized block design with floral origin and geographic zones as main principal factors were used to assess the effect of these factors on stated parameters. Moisture content, ash, pH, acidity, viscosity and colour were determined as per methods described in AOAC (2005). Phenolic content was determined using modified Folin Ciocalteau method and antioxidant activity using Ferric Reducing Antioxidant Power (FRAP) assay. Sugar profile and quantification was performed using Shimadzu high- performance liquid chromatograph equipped with refractive index detector (RID-10A) as per method 977.20 in AOAC (2005). Minerals: copper, zinc, lead, iron, calcium and magnesium were determined using Atomic Absorption Spectophotometer (AAS). sodium and potassium using flame photometer as described by AOAC standard methods (2005). Quantitative Descriptive sensory analysis was done using a panel of 8 trained judges using 9 point an unstructured line scale for rating the intensity of an attribute while consumers acceptability study was done using a 9 point hedonic scale as described by Lawless and iii Heyman (2010) to evaluate acceptability for the attributes of colour, aroma, viscosity and general acceptability. Data were analysed by R software for univariate Analysis of Variances (ANOVA) to determine significant variations between the main factors. Means were separated by Tukey's Honest significant differences at p < 0.05. Multivariate Principal Component Analysis (PCA) was done by Latentix software and Cluster analysis was done by Latentix and R software to determine the systematic variations in the study variables. Most properties of honey varied significantly (p < 0.05) between geographical zones and floral origins with values of honey from Mioinbo floral origin being higher compared to honey samples from Acacia origin. Northern zone honey samples within Mioinbo origin had significantly (p < 0.05) higher moisture content, ash and acidity while Lake zone honey samples had significantly (p < 0.05) higher viscosity. Southern highland Mionibo honey samples had higher colour value on pfund scale. PCA results showed that colour and viscosity had more effect on the variability of physico chemical properties. Phenolic content (mg gallic acid equivalent/100g) and antioxidant activities as pM Fe2‘/100g were significantly (p < 0.05) higher in the Northern zone than in other zones. Honey samples from Mioinbo had significantly higher values of 127.9 - 395.2 pM Fe2+/100g than Kcacia honey samples with values of 119.5 - 168.8 pM Fe27100g between floral origins. Bi plot from principal component analysis, PCI explained 99.2% of variations and showed that both parameters (total phenol and antioxidant activity) had higher effect on the variability. A strong correlation (R2 = 0.929 and R2 = 0.869) between phenolic contents and antioxidant activities were observed in both Mioinbo and Acacia honey samples. respectively. iv There were significant differences (p < 0.05) in fructose, sucrose and total sugars between zones and floral origins. Fructose was found to be the most dominant sugar in the honey samples in each zone and floral origin with the highest contents observed in Acacia honey samples (44.7 - 47.0 g/lOOg) than their Miombo counterpart (39.5 - 42.0 g/lOOg). Glucose, the second dominant sugar was not significantly (p > 0.05) different between floral origins and among zones. Sucrose occurred in small amounts in honey samples from all zones and floral origins. The variation of each sugar between zones within each origin were also significant (p < 0.05) with Northern zone had the highest content of total sugar. PCI bi plot explained 90.7% of total variations with high contribution from fructose and total sugars. Potassium was observed to be the most abundant macro minerals in the honey samples (380.2 - 3488.1 ppm) followed by magnesium (128.1 - 2409.5 ppm), calcium (86.3 - 336.6 ppm) and sodium (78.1 - 165.3 ppm) while iron was the most abundant micro minerals (24.5 - 36.0 ppm) followed by zinc (2.5 - 8.7 ppm) and copper (0.2 - 0.5 ppm). The northern zone honey samples from both floral origins had lead contents above maximum allowed limits as per Tanzania honey standard. The variations in macro minerals between zones were significant with Northern zone having higher contents of Ca. Mg, K and Na in samples originating from Miombo floral origin. Furthermore, the variations in mineral contents between floral origins were also significant with honey samples from Miombo floral origin having significantly much higher content of minerals than Acacia honey samples. Multivariate cluster analysis revealed grouping/similarities of zones according to the mineral they contain. In quantitative descriptive analysis, variations in mean intensity scores of attributes between zones were significant (p < 0.05) in aroma, clarity, hue, viscosity and whiteness, respectively for honey samples from Miombo origin. Southern zone showed high values in aroma and hue, Central zone had high viscosity values while Coastal zone had highest V values in clarity and whiteness compared to other zones. In sample from Acacia origin. Northern zone had significantly (p < 0.05) highest scores in aroma, viscosity and whiteness where Lake zone had high values in clarity and Central zone had high values in hue. Therefore, the study has revealed that fructose was the most abundant sugar in the honey samples while potassium and iron arc the most abundant macro and micro minerals in honey samples under the study. Furthermore, geographical zones and floral origins have significant influences on physical chemicals properties, total phenols and antioxidant activities sugar, minerals and sensory properties of honey samples from five geographical zones and two floral origins in Tanzania. It is therefore recommended that, honey be included in human diet due to its high nutritional and antioxidant properties. In addition, further research be undertaken to create a data base which will successfully enable characterization of Tanzania honey, thus increasing its competitiveness in the local and international market.view
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    Quality evaluation of fresh selected orange fleshed sweet potatoes in lake zone of Tanzania
    (Science Publishing Group, 2023) Chuwa,Caresma; Zacharia,Abdulsudi Issa
    Vitamin A Deficiency (VAD) is a public health problem in developing countries in children below five years. Orange Fleshed Sweet Potatoes (OFSP) are rich in β-carotene a pre-cassor for vitamin A. Being a cheap and affordable source, can be utilized by incorporating in staple foods to combat VAD in developing countries. OFSP fresh roots (Ejumla, Jewel and Carrot dar) were collected from Ukerewe and Misungwi District, Mwanza region for quality evaluation. The findings of the study indicated that there was considerable variance in the nutrient content across the several types of OFSP that were tested. Among the varieties that were chosen for analysis, it was found that Jewel had the maximum quantity of β-carotene (113,565 ± 1.45 μg/100 g), whilst Carrot dar had the lowest concentration (5,165 ± 3.38 μg/100 g). In addition to β-carotene, the aforementioned varieties of OFSP exhibited a diverse array of nutrients, including protein (3.82% - 8.86%), fat (0.32% - 0.51%), fibre (1.83% - 3.15%), carbohydrate (87.05% - 92.60%), ash (0.86% - 1.09%), ascorbic acid (15.04 mg/100 g - 17.27 mg/100 g), and energy content (385.19 Kcal/100 g - 392.92 Kcal/100 g). Several minerals were discovered in the selected OFSP varieties. Jewel exhibits a high content of essential minerals such as calcium (44.30 mg/100g), iron (1.34 mg/100g), zinc (0.35 mg/100g), and potassium (317.12 mg/100g). Conversely, Ejumla is characterized by its notable sodium (112 mg/100g) and magnesium (2.73 mg/100g) content, making it a valuable source of these minerals. Based on the findings, it can be concluded that OFSP possesses a high concentration of essential nutrients that play a crucial role in addressing both macro and micro-nutrient deficiencies in developing countries. Hence, individuals should integrate Orange Fleshed Sweet Potatoes into their primary food sources as a means of enhancing the overall nutritional value.
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    Diversity Of Underutilised Vegetables In Africa And Their Potential In The Reduction Of Micronutrient Deficiency:A Review
    (Science publishing Group, 2023) Zacharia,Abdulsudi Issa; Majaliwa,Nuria Kudra; Nyamete,Frida Albinusi; Chove,Lucy Mlipano
    Micronutrient deficiency affects all groups worldwide and is a major public health issue. It has devastating effects on all ages, especially in sub-Saharan Africa. It causes anemia, night blindness, increased mortality in children and pregnant women, osteoporosis in adults and rickets in children, lower infectious disease resistance, weariness, and cognitive impairment. Recent attention has focused on micronutrient deficits. Fortunately, these micronutrients are abundant in vegetables. Many African vegetables are endemic due to various weather variations. Diverse geographical areas on the continent allow for exotic and indigenous vegetable kinds. In Africa, many African Indigenous Vegetables (AIVs) are grown and eaten. Exotic veggies are popular in cities, but rural Africans still prefer indigenous crops. Despite their availability, most of the indigenous vegetables are underutilised and have not been adequately explored due to the decreased attention to their production, consumption and utilization. Due to their diversity, they have a great potential to contribute to food security by providing nutrient rich healthy diets. They are rich in vitamins and minerals and hence make a potential source of micronutrients that can help reduce the reported deficiencies. This paper provides a literature review on the wide variety of underappreciated vegetables grown in Africa, their health benefits, and their potential to alleviate micronutrient shortages. It also investigates the barriers to increasing consumption and explores some of the strategies that have been employed to address these problems. Due to their significant role in ensuring food and nutrition security, along with their rich nutrient composition, there exists an urgent imperative to enhance public awareness regarding their consumption and the attainment of nutritional security.
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    Microbiological quality and safety of poultry processed in Africa: a review
    (Academic Journals, 2024) Mugabe,Noémia André; Zacharia,Abdulsudi Issa; Kussaga,Jamal
    Poultry is the second most consumed meat in the world. In Africa, chicken production and processing are practiced both formally and informally, with smallholders constituting the majority in this sector. Informal practices are vulnerable to the production and processing of chicken, which is easily contaminated by pathogens such as Escherichia coli, Staphylococcus aureus, Salmonella, and Campylobacter. The growth of the poultry industry in Africa, coupled with intensive production, has led to the indiscriminate use of antibiotics and the development of antimicrobial resistance, posing a risk to the health of consumers. However, there are limited studies evaluating the quality and safety of chicken consumed in Africa. Several studies report that chicken is the main vehicle for pathogens related to foodborne diseases, suggesting that foodborne diseases pose a threat to human health. Adequate hygiene and safety practices by producers and processors are suggested as the main intervention. These practices would need to be followed by laboratory analysis and inspection to assess chicken quality and prompt changes in behavior, attitudes, and practices to reduce contamination and promote the rational use of antimicrobials. This review provides an overview of the quality and microbiological safety of processed chicken in Africa. It delves into details about the poultry sector, covering production, slaughter, and processing of chicken. The review highlights the sources and mechanisms of poultry contamination, describes diseases transmitted through the consumption of poultry, presents data on the quality and microbiological safety of chicken, proposes good practices in chicken production and processing, discusses the occurrence of antimicrobial resistance and antibiotic residues, and presents alternatives against contamination and antimicrobial resistance as potential tools for the production of healthy and safe foods.
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    Formulations, standardization and quality evaluation of ready-to-cook pancake (cheela) mix for children
    (Science Publishing Group, 2023) Chuwa,Caresma; Dhiman,Anju; Saidia,Paul; Zacharia,Abdulsudi Issa
    The purpose of this study was to investigate the quality of formulated ready-to-cook pancake (cheela) mix from blends of rice flour supplemented with ripe pumpkin powder with table salt, black salt, garam masala, kitchen king masala and refined oil was kept as constant (base recipe), rice flour supplemented with chickpea flour, rice flour supplemented with soybean flour and rice flour supplemented with green gram flour with pumpkin powder, table salt, black salt, garam masala, kitchen king masala and refined oil was kept as constant. Refined oil was used for the preparation of pancake (cheela) mix for serving. From each blend, six recipes were formulated, standardized and subjected to consumers for sensory evaluation. The best recipes from each blend based on sensory evaluation were prepared and referred to as R 1 , R 2 , R 3 and R 4 . R 1 (75% rice flour+ 25% pumpkin powder), R 2 (65% rice flour +10% chickpea flour), R 3 (55% rice flour+20% soybean flour) and R 4 (45% rice flour+30% green gram flour) were prepared and kept to the Aluminiun Laminated Pouches (ALP) and glass jars for nutritional characteristics evaluation. Based on sensory evaluation, the ready-to-cook pancake (cheela) mix for serving from the recipe (R 1 ) had the highest overall acceptability score of 8.79 however all recipes had scores above the acceptable limit. The ready-to-cook pancake (cheela) mix supplemented with soybean flour (R 3 ) exhibited the highest nutritional values for crude protein 25.76%, crude fat 8.78 %, crude fibre 7.04 % and total energy 382.46 Kcal/100g. Soybean flour is very nutritious therefore, it should be incorporated into staple foods for children in least-developed countries to alleviate malnutrition, especially Protein Energy Malnutrition (PEM). The recipes of the present study are relevant to the Government, NGOs and other agencies to eradicate malnutrition
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    Voluntary maize flour fortification in Tanzania: adequacy of small-scale processors' implementation of the quality assurance and quality control programmes
    (Science Publishing Group, 2023) Zacharia,Abdulsudi Issa; Mareni,Gudila Boniface
    This study systematically evaluated the implementation of fortification practices, including quality assurance and quality control, among small-scale processors to ensure regulatory compliance. A descriptive cross-sectional survey was conducted in Ubungo district (Dar es Salaam) and Morogoro municipality, Tanzania, involving 38 processors. Data collection relied on observational checklists and IBM SPSS ® version 20 for analysis. Descriptive statistics revealed critical insights. Cleanliness and sanitation standards were met in only 36.8% of warehouses and 42.1% of production areas, underscoring hygiene deficiencies. Alarmingly, 26.3% of micronutrient premixes were inappropriately stored near heat-generating milling machines. Written procedures for quality assurance and quality control were virtually absent, with just 2.6% of processors having such documentation. A mere 13.2% of processors conducted quality checks on fortified maize flour to confirm micronutrient presence. This study identified pervasive shortcomings in quality control and assurance practices among small- scale processors. Hindrances included inadequate training in fortification standards, limited processing capacity, and constrained access to quality control facilities. Strengthening these practices is imperative to ensure the consistent delivery of safe, high-quality fortified maize flour, essential for the nutritional well-being of target populations. This action holds significant public health and food safety implications.
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    Microbiological quality of rabbit fish (signus sutor) and food safety practice of fish handlers from selected landing sites in Zanzibar
    (2023) Mohamed,Zeyana Nassor; Zacharia,Abdulsudi Issa; Nyamete,Frida
    The study aimed to evaluate the handling practices and microbiological contamination of pathogenic bacteria in Rabbit Fish (Signus Sutor) from Zanzibar, specifically at four landing sites: Malindi, Mazizini, Kizimkazi, and Matemwe. A semi-structured questionnaire and checklist were used to assess hygiene practices by fish handlers, and swabbing method was used to assess cleanliness of the boat and landing floor before fish were collected for consumption. Standard methods for microbial analysis (ISO7218:2007(E)) were used to analyze Total viable counts, S. aureus, E. coli, and Salmonella. The mean total viable (TVC) ranged from 2.82-3.30 log CFU/g across landing sites. S. aureus was the most frequently isolated bacterium, with an isolation rate of 53.33% in Malindi, 60% in both Mazizini and Kizimkazi, and 46.67% in Matemwe. E. coli was present but less frequently, with isolation rates of 6.67% in Malindi, 33.33% in Mazizini and Kizimkazi, and 20% in Matemwe. Salmonella spp was absent in all samples, with a 0% isolation rate across landing sites. There was positive correlation of 0.59 and 0.65 between fish contamination and swab samples from boats and landing floors respectively. Inadequate practices by fish handlers, such as not wearing gloves, neglecting health checks, and insufficient training, were revealed. The facilities used were also poor, with poor sanitation and low-quality raw materials. The findings emphasize the urgent need for intervention measures to enhance fish quality and safety in Zanzibar, including improvements in raw materials, infrastructure, training, and good practices throughout the fish value chain.
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    Microbial inactivation mechanism and properties of slightly acidic electrolyzed water: a review
    (Science Publishing Group, 2023) Zacharia,Abdulsudi Issa
    Slightly acidic electrolyzed water (SAEW) obtained by electrolyzing 2-6% dilute hydrochloric acid in a chamber without membrane is novel non-thermal sanitizer widely used in the sterilization of foods such as fruits, vegetables, and meat owing to its effective antibacterial activity and low operating costs. Despite the well-documented and validated antimicrobial and sporicidal properties of SAEW, its precise mode of action against bacteria and bacterial spores remains uncertain and subject to ongoing debate. The primary aim of this review article is to scrutinise the active constituents of SAEW that contribute to its antimicrobial properties. Additionally, the review critically elucidates the mechanisms by which SAEW effectively inactivate vegetative bacteria cells and spores, based on a comprehensive scrutiny of existing literature. It is demonstrated that the application of SAEW can kill vegetative bacterial cells by the disruption of their cellular membrane, disruption of their intracellular reactive oxygen species (ROS) balance, and lowering their ATP levels, deactivation of key enzyme and damaging DNA affecting other bacterial cells vitals. Bacterial spore inactivation by SAEW being achieved through the induction of structural modifications in the spores, including coat damage, mutagenesis, and alterations in the properties of the inner membrane (IM).
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    Evaluation of heavy metals contamination in rabbit fish (signus sutor) from selected landing sites in Zanzibar, Tanzania
    (Journal of Food Safety and Hygiene, 2023) Mohamed,Zeyana Nassor; Zacharia,Abdulsudi Issa; Nyamete,Frida
    The increase of heavy metals concentrations in aquatic and terrestrial environments and their toxicity is of global concern. The bioaccumulation of toxic metals in fish poses a serious risk to human health when consumed. This study assessed the quality of Rabbit fish (Signus Sutor) and their associated health risks from four landing sites (namely Malindi, Mazizini, Kizimkazi and Matemwe) in Zanzibar. The concentrations of toxic metals, including Lead (Pb), Cadmium (Cd), Copper (Cu), Chromium (Cr), Nickel (Ni), and Arsenic (As), in the fish muscle were scrutinized using inductively coupled plasma optical emission spectrometry (ICP-OES). The detected mean concentration (mg/kg) of Pb, As, Cr, Cd, Cu, and Ni at Malindi were 0.25±0.14, 2.22±0.44, 0.02±0.02, 0.01±0.00, 0.02±0.02 and 0.00±0.00 respectively; at Kizimkazi were 0.39±0.39, 2.30±0.44, 0.11±0.01, 0.07±0.04, 0.17±0.13 and 0.15±0.04 respectively: at Matemwe were 0.38±0.12, 0.52±0.14, 0.04±0.02, 0.05±0.01, 0.65±0.21 and 0.09±0.03 respectively; and Mazizini were 0.21±0.12, 5.56±1.37, 0.02±0.02, 0.03±0.01, 0.05±0.02 and 0.15±0.05 respectively. The mean concentration levels detected for all the elements in the fish gathered from all four landing sites were below international and local maximum (FAO/WHO) permissible limits for human consumption, except for Arsenic (As) and lead (Pb). The study also investigated the relationship between fish size and metal concentration which shows a positive correlation for Cu and Ni. However, it was negative for the remaining metals, possibly due to ecological and metabolic differences. The study emphasizes the necessity for regular monitoring of the marine environment and enforcement of hygienic regulations, as well as the treatment of land-based pollutants before they are discharged into the marine environment to protect fish quality
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    Evaluation of bacteriological quality and safety of sugarcane juice locally processed and vended in Dar es salaam city, Tanzania
    (Tehran University of Medical Sciences, 2023) Issa-Zacharia,Abdusudi; Rwabunywenge,Stephen Paul
    The prevalence of foodborne illness linked to the intake of freshly squeezed juices sold by street vendors is on the rise, despite the widespread use of these beverages by millions of people in developing nations. Hence, a study was undertaken to evaluate the microbiological standard and safety of locally processed and street-vended sugarcane juices in Dar es Salaam to ascertain their present condition. A total of 60 samples of sugarcane juice were gathered and examined. Street vendors involved in the sugarcane juice business were interviewed followed by physical-chemical and microbiological laboratory analysis. The pH of unpasteurized sugarcane juice was 4.8 and 4.9 for iced and raw, respectively while the pH for pasteurized and pasteurized juice in which citric acid was added were receptively, 4.3 and 3.1. The average level of titratable acidity was 0.083%. The Soluble solids (°Brix) of unpasteurized raw, iced and pasteurized sugarcane juice ranged from 12.2- 22.1, 2.4-13.8 and 14.1-15.8. The total plate counts (TPC) of unpasteurized sugarcane juice showed a mean of 5.592 and 5.64 log cfu/mL for raw and iced sugarcane juice, respectively. About 90% of samples were above TBS and Codex recommended maximum limits of 3.7 to 4 log cfu/mL or 5×103- 104 cfu/mL. Unpasteurized raw and iced sugarcane juice were contaminated with 1.79 and 2.10 log cfu/mL of E. coli while no typical Salmonella spp. was detected in all 60 samples. The study concluded that the microbiological quality and overall handling practices associated with unpasteurized sugarcane juice sold in Dar es Salaam City were substandard.
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    Application of slightly acidic electrolyzed water as a potential sanitizer in the food industry
    (Hindawi, 2024-02-29) Issa-Zacharia,Abdulsudi
    Te food industry has extensively explored postharvest microbial control, seeking viable technologies to ensure food safety. Although numerous chlorine-based commercial sanitizers serve this purpose, many are plagued by constraints such as instability and diminished disinfectant efcacy. Tese issues arise from exposure to organic matter in wash water, light, or air. As an innovative and promising alternative, slightly acidic electrolyzed water (SAEW) has emerged, captivating attention for its robust sterilization potential and eco-friendliness in agricultural and food sectors. SAEW generated via electrolysis of a diluted hydrochloric acid (HCl) solution with concentrations ranging from 2 to 6% or aqueous solution of sodium chloride (NaCl) in a nonmembrane electrolytic chamber is reported to possess equivalent antimicrobial properties as strong acidic electrolyzed water (StAEW). In contrast to traditional chlorine sanitizers, SAEW leaves less chlorine residue on sanitized foods such fresh-cut fruit and vegetables, meat, poultry, and aquatic products due to its low available chlorine concentration (ACC). Its near neutral pH of 5 to 6.5 not only renders it environmentally benign but also mitigates the production of chlorine gas, a contrast to low pH conditions seen in StAEW generation. Te bactericidal efect of SAEW against various strains of foodborne pathogens is widely believed and accepted to be due to the combined action of high oxidation-reduction-potential (ORP) reactions and undissociated hypochlorite/ hypochlorous acid (HOCl). Consequently, a burgeoning interest surrounds the potential of SAEW for sanitation in the food industry, ofering an alternative to address shortcomings in sodium hypochlorite solutions and even StAEW. It has been hy- pothesized from a number of studies that SAEW treatment can increase the quality and nutritional value of harvested fruits, which in turn may enhance their ability to be stored. Terefore, SAEW is not only a promising sanitizer in the food industry but also has the potential to be an efcient strategy for encouraging the accumulation of bioactive chemicals in plants, especially if it is used extensively. Tis review encapsulates the latest insights concerning SAEW, encompassing its antimicrobial efectiveness, san- itization mechanism, advantages vis-à-vis other sanitizers, and plausible applications across the food industry
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    Bushmeat consumption in Africa: a microbiological safety challenge?
    (Asian Food Science Journal, 2023-09-12) Ahouanse Gwladys Gloria Amen; Issa-Zacharia Abdulsudi; Majaliwa Nuria
    Objective: This review analyzed the microbiological safety of bushmeat consumed in Africa over the past decades. Methodology: Previous Studies mainly focused on large animals like antelopes and smaller ones like grasscutter. Most microbes studied were similar to those in domestic animal meat, except for rare pathogens such as Salmonella spp, E.coli. Sampling, experiments, and microbe prevalence varied among studies. Results: All studies confirmed the presence of zoonotic pathogens dangerous to human beings. Therefore, more investigations are needed, especially for the chronic and severe cases of pathogens, since only few studies have addressed the bushmeat's microbiological safety in Africa. Conclusion: Efforts should be made to improve bushmeat safety and public health in Africa. New policies and public regulations must be developed and implemented to ensure hygienic and legal bushmeat production in Africa.
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    Nutritional evaluation of a complementary food based on dates, millet, orange-fleshed sweet potato and moringa leaf powder
    (Asian Food Science Journal, 2023-10-18) Selemani Salha Yustus; Issa-Zacharia Abdulsudi; Chove Lucy Mlipano
    The aim of this study was to formulate highly nutritious infant foods. The nutritional quality of a complementary porridge based on pearl millet, orange-fleshed sweet potato, dates and mixed with Moringa leaf powder was assessed using standard methods. A total of 7 formulations were produced, with compositional proportions calculated on the basis of recommended daily allowances (RDAs) for children aged 1-2 years. The linear regression method was used to combine the samples into different formulations to meet FAO/WHO/UNICEF requirements. The results obtained revealed that the nutritional composition of the flour on a dry weight basis was as follows: crude fiber: 2.6-3.3 g/100g, ash: 1.9-2.13 g/100g, crude fat: 0.66-1.38 g/100g, crude protein: 8.34-11.07 g/100g, carbohydrates: 73-77 g/100g and 346-352 g/100g energy. Iron, zinc and calcium contents were 4.5-6.3, 1.46-1.81, 183-240mg/100g respectively, and vitamin A content was 308-497 μg/110g. The incorporation of Moringa leaf powder improved the nutritional quality of the supplementary feed.
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    Effects of dietary supplements of DHA-enriched micro algae diet on physical and technological properties of dairy cow milk fat
    (2023-08-25) Issa-Zacharia Abdulsudi
    This study examined the effect of dietary supplementation of DHA-enriched micro algae diet on physical and technological properties of dairy milk fat in terms of the dynamic crystallization and melting behaviour. Two dairy cows were subjected to feeding regime of DHA-enriched micro algae diet and control diet. The experiment was carried out during 21-d to determine the normal (control) and DHA-enriched micro algae diet modified milk fat that were taken for further analysis. The melting and crystallization behaviour of the milk fat from the cows fed control and DHA-enriched micro algae diets was studied using differential scanning calorimetry (DSC), Q1000 (TA Instruments, New Castle, DE, United States). DHA-enriched micro algae supplementation strongly affected the melting and crystallization properties of milk fat. Generally, the onset temperature (°C) of milk fat crystallization was significantly lower in DHA-enriched milk fat as compared to the control. The quantity of heat released by fat crystallization expressed as J/g (peak area) was significantly lower in enriched milk fat. DHA-enriched milk fat also had a lower peak maximum temperature as compared to control in all samples investigated. All melting curves displayed two peaks (lower melting and higher melting peaks) and for melting peaks, DHA-enriched milk fat melted at significantly lower temperature as compared to the control indicating an increase in the degree of unsaturation of milk fat. Melting offset temperature was significantly lower for DHA- enriched milk fat as compared to the control. It can be concluded that from the results of this study, micro algae supplementation significantly altered the milk fat composition and positively affected melting and crystallization behaviour of milk fat.
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    Functional and sensory quality of complementary food blended with moringa leaf powder
    (European Journal of Nutrition & Food Safety, 2023-08-23) Selemani Yustus Salha; Issa-Zacharia Abdulsudi; Chove Mlipano Lucy
    Functional and Sensory Quality of Complementary porridge made from Moringa Leaf Powder blended with Pearl millet, Orange-Fleshed Sweet Potato, Dateswas evaluated using standard methods. The Pearl millet grain flour, Moringa leaf powder and dates were blended in ratios of 90:2.5:7.5 [PmMD1], 95:2.5:2.5 [PmMD2], 88:3:9 [PmMD3] respectively. Also, Pearl millet grain flour, Moringa leaf powder and Orange fleshed sweet potato were blended in ratios of 95.5:2:2.5 [PmMP1], 88:2:10 [PmMP2], 95:2.5:2.5 [PmMP3], respectively. The ratios were calculated based on Recommended Daily Allowances (RDA) for children aged 1-2 years. Control sample was blended with Pearl millet, Dates and Orange fleshed sweet potato in a ratio of 50:15:35 [PmDP], respectively. A significant difference (p<0.05) in bulk density and viscosity were observed due to the difference in amounts of Orange fleshed sweet potato and Dates. No significant difference (p>0.05) in water absorption capacity was observed. Sensory evaluation showed significant difference (p<0.05) between all samples and in all sensory parameters namely aroma, taste, color and overall acceptability. The sample PmDP was the most accepted in terms of colorwhereas PmMP2 was the most accepted in terms of aroma, taste and overall acceptability. Quantitative descriptive analysis was conducted to determine the intensity of color, aroma, sweetness, thickness and grittiness among the samples. No significant difference (p>0.05) in the intensity of color, aroma, thickness and grittiness. There was a significant difference in the intensity of sweetness among the samples (p<0.05) and the mean values ranged from 4.2-1.9. The control sample [PmDP] had the highest value in sweetness intensity as it contained Orange fleshed sweet potato and Dates which are both of a sweet nature. A PCA biplot was drawn to indicate the association between the samples and the attributes. All ingredients used in this study had a different contribution in the functional quality of the porridge together with the sensory quality.Orange fleshed sweet potato and Dates generally improved the sensory quality of the porridge samples.
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    Detection of proteolysis in high temperatures treated milk by reverse phase high performance liquid chromatography (RP-HPLC)
    (Academic Journals, 2014-02) Chove Lucy M.; Grandison S. Alistair; Lewis Michael J.; Issa- Zacharia Abdulsudi
    Proteolysis of UHT milk during storage is one of the problems affecting the dairy industry worldwide. Native enzymes have been implicated as being the main cause of spoilage of such milk. In the current study, reverse phase high pressure chromatography (RP-HPLC) method was used to detect proteolysis by native enzymes in high temperature heated milk. The aim of this research was to assess susceptibility of milk to proteolysis by native enzymes, after being subjected to various temperature- time processing conditions. Samples of raw and heated milk were clarified prior to analysis. Clarification was carried out to obtain pH 4.6 and 6% TCA soluble extracts, which were injected into RP- HPLC after filtration. This method confirmed that raw milk and milk processed at 85°C /15 s were the most proteolysed, indicating that the high temperatures employed during this study (110, 120, 130 and 142°C for 2s) inactivated the native enzymes. The RP-HPLC method is a useful method for the detection of proteolysis in milk.