Browsing by Author "Getachew, Paulos (PhD)"

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    Chemical Composition and Antihypertensive Properties of Salt Extracted From Ash of Marsh Barbel (Hygrophilia Schulli) Grown on Gambella, Ethiopia
    (Addis Ababa University, 2019-01-05) Mengistu, Degsew; Getachew, Paulos (PhD); Baye, Kaleab (PhD)
    In some parts of Ethiopia particularly, in Gambella (Anuaq), vegetable salt extracted from ash of plant parts is consumed as dietary salt and for therapeutic purposes of heart disease, liver disease, kidney failure, blood pressure and diabetics traditionally. The aim of this study was to investigate selected minerals composition, sensory acceptability and anti-hypertensive properties of vegetable salt extracted from Hygrophilia schulli. The salt was prepared from the ash obtained by burning stems of the Hygrophilia schulli. The Macro and micro minerals were determined by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and toxic metals were analyzed by Flame Atomic Absorption Spectroscopy (FAAS) accordingly. The mineral analysis showed that the salt was potassium rich and sodium poor with sodium to potassium ratio of 0.05. The vegetable ash was free from harmful metals like mercury, cadmium, chromium, arsenic and other analyzed toxic metals (Lead and Nickel) were below the Provisional Tolerable Weekly Intake (PTWI) specified European Union. The values were 0.0026mg/Kg for lead and 0.0052mg/Kg for Nickel. The major anions in this salt were chloride, carbonate and sulfate but chloride was significantly (p<0.05) greater than carbonate and sulfate. The sensory acceptability (taste attribute) of vegetable salt was relatively low value (20%) when compared to common salt (80%). However, the sensory acceptability of the combination of vegetable and common (commercial) salt in different proportion was highly accepted than common salt. Finally, the antihypertensive property of the salt was determined invivo Wistar rat experiment. Based on this, rats fed on salt from Hygrophilia schulli showed a significant (p<0.005) lower systolic, diastolic and mean blood pressure compared to normal fed and common salt fed rat groups. Results from this study indicated that vegetable salt extracted from Hygrophilia schulli can be a potential substitute of common salt with comparable sensory attributes, especially for people with hypertension and related chronic diseases.
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    Comparison of Nutritional and Sensory Quality of Vegetables Grown on Aquaponics Technology and Conventional Produces
    (Addis Ababa University, 2019-06) Wolde, Dereje; Getachew, Paulos (PhD); Tadesse, Abebe (PhD)
    Aquaponics is one of a sustainable and alternative food production sector that integrates aquaCUlture with hydroponics. It is an emerg.ing part of aquaculture that uses the natural interaction between bacteria, fish and plants to change waste into clean water. Compared to soilbased agriculture and aquaculture production methods, aquaponics has many benefits including re-use of the wastewater from the growing fish, production of two commodities from a single system and expanded food production by urban residents. For the sustainability of aquaponics, the nutritional and sensory quality of the produces should be equivalent or better than the conventional produces. Thus, this study was aimed to compare the nutritional quality and customer preference of lettuce (Lacnlca sativa L.) and kale (Brassica carinata) grown on aquaponic system with that of conventionally grown in soil-based system. Proximate composition of lettuce and kale was determined using standard methods of AOAC and mineral content was determined by Inductively Coupled Plasma Optical Emision Spectroscopy. Sensory test was also determined by using discriminatory, preference and rating acceptance test methods. Accordingly, the aquaponic lettuce from Shewa Robit site had a significant (p
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    Effect of Drying Methods and Egg Types on Basic Quality and Shelf Stability of Whole Egg Powder
    (Addis Ababa University, 2020-11-11) Abrha, Esayas; Baye, Kaleab (PhD); Getachew, Paulos (PhD)
    Weak market linkages, unavailability of cold-storage, and the significant loss of eggs due to breakage and low shelf-life contribute to the unaffordability and the low consumption of eggs in low-income countries like Ethiopia. Powdered dried egg provides a convenient alternative to this problem. The effect of spray- and oven-drying of eggs from local (Ethiopian) and exotic (imported) chicken breeds on the physical, techno-functional, nutritional composition, shelf stability, and organoleptic attributes of egg-powders was evaluated. Exotic (n= 150) and local (n= 140) eggs were spray/oven-dried. Experimental design used was completely randomized design. The yield, bulk-density, flowability, and the foaming-, emulsification-, and water/oil absorption- capacity of the egg powders were evaluated following standard procedures. The concentrations in energy, protein, fat, ash, and minerals were determined. The egg-powders’ contribution to nutrient requirements from complementary foods and their potential use as an alternative protein source in ready to use therapeutic foods (RUTF) were evaluated. Local eggs had higher energy and fat content, whereas protein was higher in the exotic eggs (P< 0.05). About 12.5 g of egg powder (one egg) can fulfill > 75%, 30%, and 40% of fat, energy, and calcium requirements, respectively. Only 6 g and 4 g of egg-powder (local/exotic eggs with oven/spray drying) are needed to fulfill protein and choline requirements, respectively. Considering the quality/quantity of proteins, egg powders can be alternative protein sources in ready to use therapeutic foods (RUTFs). Functional properties including emulsification capacity, water/oil absorption capacity, and soluble protein content between oven-dried local and exotic eggs were significantly different (p<0.05). However, this trend was no observed for the spray-dried powder (p<0.05). The sensorial quality of the whole egg powder was acceptable. Whole egg powders from local eggs generally had the highest (p<0.05) overall organoleptic rating. The total aerobic mesophilic bacteria and total coliforms were in the range of (2-7) and (0.42-5) CFU/g respectively over the storage period of dried whole egg. Salmonella was also absent during the storage period of dried whole egg. In conclusion, drying eggs into powder can constitute a food systems’ intervention that improves the safety and quality of diets, reduce loss, and increase eggs’ affordability in low-income countries like Ethiopia. In general, whole egg powders produced by spray and oven drying methods are generally accepted and serve as good alternatives to fresh eggs
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    Evaluating Quality Deterioration of Used Frying Vegetable Oils and Improving the Quality Using Adsorbent Treatment
    (Addis Ababa University, 2018-03-05) Nuru, Zehara; Getachew, Paulos (PhD)
    Frying is the most commonly used cooking method in food preparation. Continuously frying food items at high temperature will result in frying oil and fried food quality deterioration. in this study as an alternative option the effects of adsorbents (betonite, ash, magnesium oxide, silica gel, and bleaching earth) to improve the quality of used frying vegetable oils (Palm and Niger seed oil) were evaluated. Accordingly, each adsorbent was mixed with 20 hours fried oils (15% w/v) at 150 oC and stirred together for 30 min. The oil was recovered through centrifugation at 4200 rpm for 15 min. Then, the physico-chemical characteristics of the fried and adsorbent treated oils were investigated on both oil types. The chemical quality parameters of palm oil increased after the prolonged frying (i.e. acid value (AV) (0.42 to 1.40) mg KOH/gm oil, free fatty acid (FFA) % (0.20 to 0.64) %, and peroxide value (PV) (1.99 to 11.00 mEq oxygen/gm of oil)). Similarly, in the 20 hrs fried niger seed oil increased values of (AV (2.24 to 8.31) mg KOH/gm, FFA % (1.13 to 4.17), PV (1.00 to 13.97) mEq oxygen/gm of oil) were found. In both fried palm and niger seed oils, magnesium oxide (MgO) treatment gave the highest improvement on the physical quality parameters. Treatment of the fried PO with 15% (w/v) (ash, bentonite, bleaching earth, silca gel and MgO) reduced the FFA% by (55, 45, 35, 65 and 61) % (silca gel > MgO > ash > bentonite > bleaching earth) respectively. Similarly, treatment of the used fried NO with the same adsorbents improved the FFA% by (61, 66, 56, 61 and 73) % respectively. The PV of the fried PO was also reduced by (55, 37, 9, 28 and 64) % respectively (MgO > ash > bentonite > silca gel > bleaching earth). Upon the same treatment the PV of the used NO was improved by (57, 43, 21, 50 and 64) % respectively. The recovery of PO after ash, ii bentonite, bleaching earth, silca gel, MgO treatment was (75, 88, 85, 70, 40) % respectively. Meanwhile with the same treatments of the fried NO, the oil recovery was (80, 88, 85, 70 and 40) % respectively. Based on both physical and chemical quality improvement effectiveness ash and MgO were selected for further objectives of the study (i.e. effect of concentration and synergism by the two adsorbents). To determine the minimum proportion of the selected adsorbents that will improve the quality of the used oil, (2.5, 5.0, 7.5, 12.5) % (w/v) of ash and MgO were used in both fried PO and NO. Treatments with 12.5% and 15.0% of ash improved the AV and FFA% of fried PO to the recommended acceptable range for human consumption. Treatments with (2.5, 5.0, 7.5, 10.0, 12.5 and 15.0) % of ash reduced the AV of fried NO gradient-wise by (26, 39, 46, 53, 53 and 60) % respectively (p < 0.05).
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    Formulation of Nutritionally Enriched Macaroni with Blends of Durum Wheat, Tef and Chickpea
    (Addis Ababa University, 2018-06) Kore, Tamrat; Getachew, Paulos (PhD); Abebe, Workineh (PhD)
    Pasta is unleavened extruded product which is made from dough of durum wheat semolina or blends of durum wheat with rice, tef, sorghum, chickpea, lupin etc. In Ethiopia, pasta products made commonly with only semolina, which has lower quality in some important nutrients such as protein, fiber and minerals as compared with other cereals and legumes. Also, semolina is in shortage of supply due to low durum wheat local production. Despite these facts, there is still lack of research on formulating pasta products from composite flour with other cereals and legumes of higher nutritional quality and production rate. Therefore, in this study the usage oftef and chickpea flours to enrich pasta products (specifically macaroni) was investigated by using Response Surface Methodology (RSM). Macaroni was prepared using composite flours of durum wheat semolina (60-100%), tef (0-40%) and chickpea (0-15%) using D-optimal mixture design. For cold press extrusion, pilot scale single screw food extruder was used. Then, first order polynomial model was applied to describe the influence of semolina, tef and chickpea proportion on nutritional composition, cooking quality, textural analysis and sensory evaluation of macaroni products. Throughout the study durum wheat macaroni (100% semolina) was used as a control. Results indicate that an increasing proportion of tef and chickpea flour significantly improved the nutritional composition of the blend macaroni (protein, fiber, fat, iron and zinc content). Incorporation of chickpea flour only up to 15% with semolina produced a macaroni comparable sensory quality with semolina macaroni. Similarly, though the addition of tef flour considerably increased the cooking loss and it also considerably improved the water absorption capacity/index of the macaroni. Protein, fiber, filmness, stickiness, cooking loss and overall acceptability were deem as common optimum parameter for macaroni formula. The formula containing 73.46% semolina, 11.55% tef and 15% chickpea was selected as the best formulation to produce a nutrient rich macaroni product with desirable cooking, texture and sensory quality. Understanding the impact of the blending ratio to improve macaroni nutritional quality was considered useful to develop pasta products. Keywords: Macaroni, tef, chickpea, cooking and textural property, RSM, D-optimal design
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    Level of Bromate, Fluoride, Microbial Load in Ozone, Ozone + Nano Filter and Ozone + Uv Treated Packed Water Brands in Ethiopia
    (Addis Ababa University, 2021-03-29) Alimaw, Elsabeth; Getachew, Paulos (PhD)
    With the increased demand and consumption of packed water in Ethiopia especially in major cities like Addis Ababa, there has been a growing concern about the quality and safety of the product. The public used to consider that all packed waters produce are safe. One of the safety concerns is the formation of bromate as disinfection by-products (DBPs) resulting from ozone treatment. Bromate has been identified as a possible human carcinogen and the level in drinking water should be strictly controlled below 10 g/L. As an alternative, UV disinfection produces minimal DBPs. However, this technology also requires high dosage for the effective removal of certain viruses. Therefore, the drawback of conventional disinfectants urges the development of alternative approaches that can improve the robustness of pathogenic removal while avoiding the formation of DBP. Thus, the development of nanotechnology, its application in water and wastewater treatment is becoming increasingly popular. But the microbial safety and quality of water upon this treatment in Ethiopia is not investigated as to our knowledge. Furthermore, in most of the bottled water brands the fluoride level, which is vital for the consumer, is not labeled as well. Therefore, the objective of this study was to investigate the level of bromate, fluoride and microbial load in ozone, ozone+ nano filter and ozone + UV treated packed drinking water brands in Ethiopia. For this purpose, thirty samples representing different brands of packed waters were randomly collected from different supermarkets, kiosks, groceries, cafes and distributer cars. The parameters investigated were bromate, fluoride, pH, Electrical conductivity (EC), Total dissolve solid (TDS), Total hardness (TH), alkalinity, turbidity and microbiological; plate count agar (PCA) and total coliform count. It was found that the concentrations of the bromate were quite different from brand to brand even upon the same treatment and water type. The level of bromate in 8 brand packed water was higher than the permissible limit. The fluoride level except ten (33.3%) brands of packed water all are not mentioned on the label of the bottle (packaged).Therefore 66.6% of the sample has not information about fluoride content. The other parameters ( PH ,Electrical conductivity, total dissolved solid, total hardness, total alkalinity and turbidity) were fulfills the requirement as per the CES and WHO guide lines and at p<0.05.But in some brands the concentrations are far below the requirement and are not recommended for drinking as per WHO standards like PH and total hardness value. All water samples were found free of the microbial contamination.
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    Physico Chemical Characteristics of Ethiopian Date Palm Fruit as Compared to Imported Date Palm Fruits from Dubai and Saudi
    (Addis Ababa University, 2021-12-21) Hussen, Sada; Getachew, Paulos (PhD)
    The consumption and production of Date palm fruit is very low, despite its long history of domestication in Ethiopia. This is mainly due to lack of awareness on the nutritional and health benefits, scant studies on physicochemical characteristics, and shortage of DPF plantation. The present study aimed to evaluate the physical characteristics, nutritional composition, antioxidant properties and glycemic index/load of Ethiopian harvest in comparison with the imported DPFs from Dubai and Saudi Arabia. Most of the physical characteristics were measured by gravimetric methods, AOAC 2000 methods were used for majority of the analysis, HPLC method for sugar profile, the average fruit weight of the DPF harvested in Saudi Arabia, Dubai, Ethiopia was 6.36 g, 5.61 g, and 4.56 g, respectively. The seed weight of the respective three DPFs was 0.84, 0.60 and 0.92g with flesh weight of (5.46, 6.41, and 3.63) g. This resulted the highest and lowest seed to flesh ratio in the Ethiopian (0.29) and Dubai (0.07) harvests, respectively. The average fruit length was 2.86mm, 2.72mm, and 3.06 mm for the Saudi, Dubai and Ethiopian harvests. The average kernel weight of the DPFs was (350.85, 311.20, 227.75)g for the Dubai, Saudi and Ethiopian harvests, respectively. The Ethiopian harvest had the smallest date size of 5.99mm. The Dubai harvest had the biggest diameter of 14.66mm. The Ethiopian and Saudi harvest DPF had bigger length than the Dubai harvest. In contrast, the Dubai harvest DPF had larger diameter (14.66 mm) than the Ethiopian (5.90mm) (p<0.05) and Saudi (13.76mm) harvests, the result of the texture implies that our date palm fruit is harder, brittle and it has high shearing and cutting effect but the date from Saudi is the stickiest and adhesive when we compare with the two date palm fruits. The Lightness redness and yellowness values of the Ethiopian, Dubai and Saudi harvest DPFs were (44.19, 4.44, 20.48), (45.15, 4.84, 8.00), and (55.50, 6.31, 7.50) (p>0.05), respectively. Having the lowest L value the Ethiopian harvest was darker in appearance than the other dates. The Dubai and Saudi DPFs had the highest moisture content of 16%; whereas the Ethiopian harvest had the lowest value of 11%. Accordingly, the DPF harvests in this study were semi-soft dates. Interestingly, the Ethiopian harvest DPF had the highest crude fiber content of 6.1%. The total and utilizable carbohydrate contents were the highest in Ethiopian harvest DPF (85.5, 79.4) %, respectively. The gross energy results increased from 311 kcal for the Dubai and Saudi harvests to the highest energy content in Ethiopian harvest DPF with 330 kcal. The fructose content in the Ethiopian, Dubai, and Saudi harvest DPFs was 12.20, 2.58, and 24.90%, respectively. Meanwhile the glucose content was 12.42, 27.05, and 26.06% for the respective DPFs. But the sucrose content was small as compared to the two reducing sugar (glucose and fructose). The dominance of reducing sugars indicated that the studied dates were soft date. The Dubai harvest DPF had the highest total sugar content (54.57%), while the Ethiopian harvest had the lowest sugar amount (29.57%).The DPPH (1, 1-diphenyl-2picrylhydrazyl) free radical scavenging assay was in order of Dubai0.05), respectively. The present study demonstrated the nutritional and physical quality and potential of Ethiopian DPF, which has low production and consumption in the country.
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    Physico-Chemical Characteristics of Sweet Lupin-Based Yoghurt Like Product Made Using Folate Producing Lactic Acid Bacteria
    (Addis Ababa University, 2019-07-07) Shemelse, Betelhem; Getachew, Paulos (PhD)
    Lupins are important crops as rich sources of protein, minerals, dietary fiber and so on. Among the legumes lupin is underutilized due to the presence of bitter and toxic alkaloids. In recent years, genetically improved sweet lupin variety with low alkaloid level is released. Yet, the consumption of sweet lupin is very low. Specially in developing countries due to lack of food products made with sweet lupin, it still remains being a neglected crop. Therefore, this study aimed to develop yoghurt like product from sweet lupin (Lupin luteus) using folate producing lactic acid bacteria. Cleaned sweet lupin seeds were soaked in water (1:9) for 12hrs. Then, the seeds were grounded into a slurry and mixed with water (1:1) followed by pasteurization at 90oC for 15min. The pasteurized slurry was subjected to fermentation using highly folate producing Lactobacillus plantarum strain with 3% of inoculum for 48hrs. Then, the proximate, mineral and folate composition of the formulated sweet lupin-based yoghurt like product was assessed. Also, physico-chemical characteristics, sensory quality of the product were evaluated. Accordingly, the hull weight of the seed was 20.60% and the water holding capacity of the seed and flour were 460 and 310%, respectively. The foaming capacity and stability of the flour were 12 and 10 %, respectively with bulk density of 0.779 g/ml. The raw sweet lupin had a moisture, crude protein, crude fat, crude fiber, total ash, total carbohydrate and gross energy contents were 8.10, 35.28, 9.36, 3.61, 3.03, 44.23 %, and 402.28 (Kcal/100gm), respectively. The yoghurt-like product had percentage value of 19.87%, 36.39, 8.95, 2.63, 2.07, 32.13 and 354.76 (Kcal/100gm) of the aforementioned nutrients, respectively. The phytate, alkaloid and tannin concentrations in the raw sweet lupin were 0.60, 0.12 and 0.05 %, respectively. While in fermented product the concentrations of the anti-nutrients were 0.16, 0.02 and 0.01 %, respectively (p≤ 0.05). The concentration of the minerals sodium, potassium and calcium in the raw sweet lupin seed were 10.36, 4.74 and 27.78 mg/100gm on dry basis, respectively. Whereas concentrations of the same minerals in the fermented yoghurt like product were 3.11,1.75 and 15.75 mg/100gm, respectively (p≤ 0.05). The concentration of the minerals iron, zinc and manganese in the raw seed and fermented product were 7.71,0.21, 0.84,0.46 and 4.4,3.75 mg/100g, respectively. The pH and titratable acidity of the raw slurry and fermented product were 5.8,0.66% and 4.8,0.99%, respectively. Folate content in raw seed was 83.02 μg/100g and was reduced to 19.45 μg/100g, during pasteurization of the slurry at 90oC for 15min. The final fermented sweet lupin-based yoghurt like product had a folate concentration of 35.96μg/100g. The viscosity of the fermented product was 309.29 (mPa-s) and the color evaluated using L*a*b* was 112.09, 96.9 and 34.81, respectively. As a new product the sensory quality of the yoghurt like product was evaluated. Accordingly, there was no significant difference in sensory attributes of texture and overall acceptability between sweet lupin yoghurt like product with sweet lupin yoghurt like product with vanilla (p≥ 0.05). Vanilla (flavoring agent) incorporated (1%)of fermented product had a higher sensory score in attributes of mouthfeel (consistency), color, flavor and taste, than the sweet lupin-based yoghurt like product. In conclusion, this study demonstrated the potential of sweet lupin to produce fermented yoghurt like product with comparable sensory acceptability providing vital nutrients such as folate and reduced anti-nutritional factors. Future studies on optimizing the processing to formulate a more acceptable product along with shelf life are recommended.
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    Physicochemical and Techno-Functional Properties of Recentlyreleased Ethiopian Bread Wheat (Triticum Aestivum. L)Varietiesgrown Inkulumsa,Arsi, Ethiopia
    (Addis Ababa University, 2020-06-06) Kasahun, Cherinet; Getachew, Paulos (PhD); Abebe, Workineh (PhD)
    Bread wheat (Triticum aestivum. L) is the most common cultivated wheat species-taking up to 95%of the wheatand staple foodfor consumersworldwide.Ethiopia is the top wheat producer in Africa and yetis not self-sufficient for the local consumption.Hence, the national wheat breeding programs in Ethiopia are trying to develop improved wheat varieties thatmainly focuses on improving grain yield and disease résistance without checking industrial quality.The objective of this studywas to investigate the physicalcharacteristics, nutritional composition, techno-functional properties, baking,and sensory quality of recently (2012 to 2018)released bread wheat varieties by the Wheat Improvement Program (WIP) of the Ethiopian Institute of Agricultural Research (EIAR). The Sixrecently released andpromising bread wheat cultivars were, Wane and Daka,Hidasse, Ogolcho, Kingbird, and Lemu,andPavon earlier released (1982)used as a check were grown at Kulumsa Agricultural Research Center under the same agronomic practice were evaluated.The standard procedures were used for all laboratory analysis and a straight dough baking method was used for bread baking process. The results showed that Thousand Kernel Weight (TKW) of the recently released bread wheat varieties were found to be in the range of 35.0g (Kingbird) to 45.5g (Hidasse) while Pavon scored 42.5g. Hectoliter Weights (HLW) of the varieties followed almost closer trend as TKW and it ranged between 78.4kg/hl (Kingbird) to 86.4kg/hl (Hidasse)whilecheck (Pavon) scored 81.1kg/hl. The single kernel characterization indicated that except for Hidasse soft wheat (32.02%) all the cultivars could be considered as hard wheat which makes them suitable for making leavened baked products. The measured protein content, crude fat, crude fiber, ash, moisture, carbohydrate, energy, starch, color, and mineralscontent in the wheat flour weresignificantly different at p < 0.05. The protein content of varieties showed that Wane (14.14) %to Ogolcho(9.74)% and gluten index Daka(94.57)% to Hidasse(59.12)% respectively. From this study, it can be concluded that the gluten qualities and quantity, protein content, and bread baking and sensorial quality of the wheat varieties were acceptable except Hidasse and can be utilized for the production of bread. Except for Hidasse, despite the visible differences in some ofthe measuredgrain physical qualities,flour qualities and thesensorial attributesbread made from the rest of evaluated wheat varieties were acceptable. Generally,Wane,Daka, and Pavon had superior performance while, Kingbird, Lemu, and Ogolcho had medium quality whereas Hidasse had poor baking quality.However,further researchesshould beconducted on these varieties on process optimizationfor better recommendations.
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    Processing Effect of Drying Methods on the Nutrient Retentions, Sensorial Quality, and Shelf-Life Stability of Papaya (Carica Papaya L.)
    (Addis Ababa University, 2021-03-06) Minuye, Masresha; Baye, Kaleab (PhD); Getachew, Paulos (PhD)
    Dietary guidelines show that more frequent consumption of fruits can prevent nutrient deficiencies and promote health. However, the perishability and unaffordability of fruits had led to very low levels of fruit consumption in low and middle-income countries (LMICs). Despite papaya fruit is one the best nutritious fruit, it is classified as a highly perishable/ low shelf-stable fruit. Therefore, to improve the shelf stability, and accessible, affordable papaya fruit, drying technologies are playing an irreplaceable role. The present study aimed to evaluate the retention of nutrients and bioactive compounds of papaya fruit (Carica papaya L) with/without ascorbic acid pretreatment, drying under different drying techniques, shelf stability of dried papaya products, and also estimate the vitamin A intakes for vulnerable populations. Yellow ripped papaya fruits (n=14), with and without ascorbic acid pretreatment were dried using i) solar drying: open-air, tray driers, and glass house; ii) refractance-window drying; iii) oven-drying, and iv) freeze-drying (control). The concentration of total carotenoid, polyphenols (TP), flavonoids (TF), and B-carotene were determined using spectrophotometry and high-performance liquid chromatography (HPLC). The fresh fruit had high moisture content (87%) and an acidic pH. The dried papaya had a water activity of 0.5-0.6. The highest TPC, TFC, total carotenoids, and carotene was found in freeze-dried papaya samples, followed by refractance-window, and solar-glass house (P<0.05). The highest retention in total carotenoids (81.5%), lycopene (78.8), and β-carotene (61.9%), relative to freeze-drying was for the refractance-window; 25 g of dried-papaya could contribute to 38% of the retinal equivalent’s requirement for young children. Whereas highest retentions of Vitamin C (47.86), bioactive compounds; total phenolic (35.5), and total flavonoid (72.75) was for the oven and refractance window dryer. Ascorbic acid pretreatment increased the retention of total carotenoids, β-carotenes, TP, and TFC (P< 0.05). The sensory attributes of dried papaya did not show a significant difference (p < 0.05), as well dried papaya can be stored for up to six months brought without a significant change of microbial load, and served as an eatable product. Refractance-window and solar-glass house drying can improve diets and constitute a promising food systems’ intervention that can increase year-round availability, accessibility, and affordability of vitamin A-rich fruits like papaya.
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    Screening Food Test Parameters to Detect Adulteration of Teff (Eragrostis Tef (Zucc.) Trotter) Flour and Injera with Non-Edible Adulterants
    (Addis Ababa University, 2018-06-06) Sileshi, Biruk; Getachew, Paulos (PhD)
    Teff (Eragrostis tef (Zucc.) Trotter) is the main staple cereal in Ethiopia that is used to prepare a fermented flatbread with a unique slightly spongy texture named injera. Majority of Ethiopian diets consist of injera which accounts for about two-thirds of the daily protein intake of the Ethiopian population. Recently, adulteration of teff flour and injera with non-edible ingredients is becoming a serious problem putting the consumers’ health at risk. Therefore, the main purpose of this study is to screen some of the common food analyses test parameters that could detect nonedible adulterants in teff flour and injera for potential use in future routine inspection analysis. In the study, simulation of the adulteration was made on two widely distributed white teff varieties, namely Quncho Teff (DZ-Cr-387) and Magna Teff (DZ-01-196). Three adulterants were selected based on the information gathered from local health bureau, namely Sawdust (organic adulterant) and two inorganic adulterants, chalk powder (calcium carbonate) and gypsum (calcium sulphate dihydrate). Based on the information gathered, the teff to adulterant ratio was (7:3). Thus, the primary investigation was conducted on this adulteration ratio. Accordingly, the analytical tests at this adulteration ratio resulted in a significant mean value difference between the adulterated and control teff flour samples. Secondary investigation was done by preparing injera using lower ratio of teff flour to adulterants (9.5:0.5), (9:1), (8.5:1.5), (8:2) and (7.5:2.5), while unadulterated (100%) teff flour injera was used as control. Ratios resulting in acceptable injera appearance were used as cut-off adulteration ratios to apply the selected test parameters. The final investigation was conducted using the cut-off adulteration ratio, on which the selected test parameters were applied to compare significant mean differences (p < 0.05) between control and adulterated teff flour and injera samples. The overall results of the physicochemical analysis showed that some parameters like crude ash, and crude fibre, and mineral analysis of calcium could be used as detection test parameters for samples as low as 5% adulteration ratio. Qualitative tests such as effervescence and precipitation are also effective tests to detect adulteration. Therefore, this study provides test parameters for preliminary teff flour and injera adulteration detection, which can further be developed by concerned bodies to come up with standard analytical procedures for the detection teff and teff injera with the tested and other similar adulterants.
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    Use of Spent Coffee Ground (Scg) as Ingredient in Bread Formulation
    (Addis Ababa University, 2018-06-02) Daniel, Teshome; Getachew, Paulos (PhD)
    Background: Spent coffee ground (SCG) is the most abundant byproduct (45%) of instant coffee production. The increase in brewed coffee consumption worldwide parallels the amount of SCG generated. Around 6 million tons of SCG is generated per year. SCG is full of nutrients, yet it is not utilized properly except as compost in few areas. It is dumped as a waste material harnessing environmental degradation. But considering its biochemical composition, it can be used as ingredient in food industries such as bakery. Objective: Therefore, the purpose of this study is to utilize SCG as a functional food ingredient in bread formulation. Through this valorization approach, the SCG incorporation proportion, glycemic index, overall acceptance and the physicochemical characteristics of the formulated bread were investigated. Materials and Methods: Wheat flour blends for (2, 4, 6, 8 and 10% of SCG) for physicochemical and sensory properties also glycemic index and antioxidant activity of the formulated bread were investigated. Results: There is considerable variation in antioxidant properties of bread baked from wheat flour and SCG has total phenolic content (TPC) 2768.53μg GAE g−1 and total flavonoids content (TFC) was 2409.24 μg QE g−1. Moisture content of SCG during collection reached to 48.98%, and dried to 8.47% to control microbial activity. The SCG based bread had improved proximate composition compared to that of wheat based bread. Specially, the SCG incorporation has shown enhancement in fiber content of the bread for instance the bread formulation with 10% SCG is 5.31 mg/100g which is much higher than the white bread which is 1.56 mg/100gm. Sensory evaluation of the new product had resulted similar overall acceptance for SCG based bread of 2% composition at p<0.05. With 2%of SCG, the bread has improved with proximate composition of protein 7.79g/100g, fiber 2.51g/100g and energy 264.48 Kcal. Compared to white bread mentioned proximate composition had significant increase for the amount with equivalent energy. In addition to proximate composition TPC and TFC of this incorporation was also improved which is 476.92μg GAE g−1 and 1154.43μg QE g−1 respectively. Use of Spent Coffee Ground (SCG) as ingredient in bread formulation 2018 x In fact, the maximum concentration of SCG (10%) based bread had also showed glycemic index (GI) of 78.68 and minimum concentration 85.57.which is less than that of standard glucose and control white bread. Baking loss of the new product is also reduced due to the effect of the fiber complex water retention activity in SCG by 9.29% for maximum concentration in the formulation. Conclusion: Spent coffee ground contains high antioxidant dietary fiber and rich with minerals. Mixing wheat flour with SCG affected physicochemical property and sensory value of the bread. Therefore, the new formulated bread can be optional source of food to people consumption.