Department of Chemical Engineering
http://etd.dbu.edu.et:80/handle/123456789/529
2024-03-29T04:49:28ZNON-ALCOHOLIC MALT DRINK PRODUCTION FROM YELLOW MAIZE USING MORINGA LEAF EXTRACT AS PRESERVATIVE AGENT
http://etd.dbu.edu.et:80/handle/123456789/1092
NON-ALCOHOLIC MALT DRINK PRODUCTION FROM YELLOW MAIZE USING MORINGA LEAF EXTRACT AS PRESERVATIVE AGENT
TSIGIE, ABERA
Non-alcoholic malt drinks with an alcohol content of less than 0.5% are consumed in many countries. Non-alcoholic malt drink is produced primarily by malting yellow maize followed by mashing, wort boiling, maturation and finishing operation. Malt is prepared in five main steps cleaning, soaking, germination, drying, and kilning. After malting, it milling, mashing, mash filter, wort boiling, cooling, maturation, filtration, and packaging operation give the final non-alcoholic malt drink. Microbial spoilage of non-alcoholic beverages is a critical issue, and for this reason, different methods were adapted to reduce spoilage. This study aimed to bring out essential micronutrients and antioxidants of moringa to combat the preservative problem through non-alcoholic malt drink products. Physicochemical and proximate analyses of raw materials ( yellow maize and moringa) were performed; i.e. total phenol content and total flavonoid content concentration were found to be 84.10
± 1.8 mg GAE / g dried and 70.79 ± 0.73 mg QE / g dried, respectively. Germinated yellow maize was a very good source of carbohydrates and energy, but lower content of protein, ash, and fat compared to non-germinated yellow maize. Central composite design (CCD) was used to examine the effects of the three independent variables (Mixing ratio, Temperature, and Time) in two-level combinations with a total number of 20 runs was applied to optimize mash production to conduct with the response variables which was the highest yield of extract. After the optimization of mash had been completed at the mashing step, maize malt was mixed by boiling wort with extracted moringa with the ratio of 5%, 10%, and 15%, and the necessary parameters of the final product were measured. The effect of moringa blended malt drink and storage time on microbial growth was characterized and the result of the analysis was compared with another commercial malt drink product produced in the country; Dashen brewery and the product obtained were tolerated. Storage of malt drink until six months, 10% and 15% of moringa substitution were suitable to minimize the growth of microorganisms and to predict extend shelf life of the product Finally, 5% and 10% of moringa substitution malt drink were acceptable in overall sensory characteristics among given samples.
2022-07-01T00:00:00ZUltramarine Blue Inorganic Pigment Production from locally available Raw Materials
http://etd.dbu.edu.et:80/handle/123456789/1091
Ultramarine Blue Inorganic Pigment Production from locally available Raw Materials
Getahun, Yifru
Synthetic ultramarine inorganic blue pigment is one of common type of blue pigment which can be easily produced from locally available geomaterials. The chemical composition of these geo-materials (sulphur and clay) was investigated by the silicate analysis method and Synthetic ultramarine blue pigment was synthesized by a solid- state calcination process. A literature review was used to select and investigate the effect of reaction temperature (750, 800 and 850 0 C), residence time (4, 5, and 6 hours), and sulfur weight amount (20.56, 21.34 and 22,06w %) on the blue pigment production process. The main blue coloring strength was identified by Commission Internationale de l'éclairage laboratory coordinate value (L*, a*, b*) where L* is the lightness value starting from 0 up to 100, a* and b* are correlation coordinates which show the coloring value between +60 and-60. The optimum process parameters for the production of blue color pigment were determined by a design expert. The optimal process parameters were a reaction time of 4.87hr. (4 hours and 52 minutes), reaction temperature (799.840 C), sulfur concentration (22.06 wt. %), and blue color value (b*=-13.13). The pigment properties were characterized by density, moisture content and color value, resistance to heat, detergent, acid, alkali and light. The crystalline nature structure and the functional group were determined by X-ray diffraction and infrared spectroscope. The quality of the blue color strength was also examined by spectrophotometer CM- 600d. According to the results of the research, there's an opportunity to produced ultramarine pigment material by using local geo-minerals.
2022-04-01T00:00:00ZFabrication of Copper Oxide Nanoparticles Using Endemic Plant Lippia Adoensis: Characterization, Testing and Optimization Studies
http://etd.dbu.edu.et:80/handle/123456789/1090
Fabrication of Copper Oxide Nanoparticles Using Endemic Plant Lippia Adoensis: Characterization, Testing and Optimization Studies
Brhan, Redae
Nanotechnology is playing a vital role in this modern era by providing many applications including in electronics, construction, health-care, catalysis, and chemical industry. Especially metal oxide nanoparticles synthesized using plant extract have got more attention in many fields of study. However, nowadays the infectious diseases are becoming one of the major challenges in health care sectors worldwide. In this work Var. Adoensis leaf and seed extract bio-treated production of copper oxide NPs for antibacterial application was achieved. It is typically simple, less energy consumption, environmentally friendly, and naturally compatible one-pot processes. In the first part, phytochemical screening was carried out, and results revealed the presence of tannins, saponins, flavonoids, glycosides, phenols, and steroids used as reducing and stabilizing agents in the copper oxide nanoparticle formation. Also, central composite design is being used for the optimization of the nanoparticles synthesizing process to study the effect of the three basic parameters namely mixing ratio, pH, and temperature has been obtained 3, 9, 60.14 and 2.99, 8.99, 60.05 respectively for both nanoparticles. The particle size, morphology, surface area, crystalline type, and optical properties of the synthesized nanoparticles were characterized using the scanning electron microscopy, elemental dispersion x-ray, ultraviolet visible spectroscopy, x-ray diffraction, Fourier transform infrared spectroscopy, surface area and particle size analyzer techniques. The results have been found to infer that both nanoparticles are monoclinic with high crystallinity but have different size and shapes and band gap energy of 3.09 and 2.77eV for copper oxide nanoparticles synthesized using Var. adoensis leaf and seed extract respectively. The synthesis of copper oxide nanoparticles was confirmed by the absorption peak at 325 and 327nm with an average size of 74.98 and 112.44nm for copper oxide nanoparticles synthesized using Var. adoensis leaf and seed extract respectively. Further, the synthesized bio-mediated copper oxide nanoparticles is found to act as an excellent antibacterial agent against two Gram-positive (Staphylococcus aureus and Streptococcus pyogen) and Gram- negative (Escherichia coli, salmonella typhi,) bacteria strains which resulted in a significant zone of inhibition (inhibition diameter between 6.5 and 26mm at different concentration) on both
nanoparticles. Overall, the proposed synthesis route of copper oxide nanoparticles using Var.
Adoensis leaf and seed extract can be utilized by pharmaceutical industry to develop effective drugs against bacterial infections.
2022-03-14T00:00:00ZNON-ALCOHOLIC MALT DRINK PRODUCTION FROM YELLOW MAIZE USING MORINGA LEAF EXTRACT AS PRESERVATIVE AGENT
http://etd.dbu.edu.et:80/handle/123456789/1083
NON-ALCOHOLIC MALT DRINK PRODUCTION FROM YELLOW MAIZE USING MORINGA LEAF EXTRACT AS PRESERVATIVE AGENT
TSIGIE, ABERA
Non-alcoholic malt drinks with an alcohol content of less than 0.5% are consumed in many countries.
Non-alcoholic malt drink is produced primarily by malting yellow maize followed by mashing, wort
boiling, maturation and finishing operation. Malt is prepared in five main steps cleaning, soaking,
germination, drying, and kilning. After malting, it milling, mashing, mash filter, wort boiling, cooling,
maturation, filtration, and packaging operation give the final non-alcoholic malt drink. Microbial
spoilage of non-alcoholic beverages is a critical issue, and for this reason, different methods were
adapted to reduce spoilage. This study aimed to bring out essential micronutrients and antioxidants
of moringa to combat the preservative problem through non-alcoholic malt drink products.
Physicochemical and proximate analyses of raw materials ( yellow maize and moringa) were
performed; i.e. total phenol content and total flavonoid content concentration were found to be 84.10
± 1.8 mg GAE / g dried and 70.79 ± 0.73 mg QE / g dried, respectively. Germinated yellow maize
was a very good source of carbohydrates and energy, but lower content of protein, ash, and fat
compared to non-germinated yellow maize. Central composite design (CCD) was used to examine the
effects of the three independent variables (Mixing ratio, Temperature, and Time) in two-level
combinations with a total number of 20 runs was applied to optimize mash production to conduct
with the response variables which was the highest yield of extract. After the optimization of mash had
been completed at the mashing step, maize malt was mixed by boiling wort with extracted moringa
with the ratio of 5%, 10%, and 15%, and the necessary parameters of the final product were
measured. The effect of moringa blended malt drink and storage time on microbial growth was
characterized and the result of the analysis was compared with another commercial malt drink
product produced in the country; Dashen brewery and the product obtained were tolerated. Storage
of malt drink until six months, 10% and 15% of moringa substitution were suitable to minimize the
growth of microorganisms and to predict extend shelf life of the product Finally, 5% and 10% of
moringa substitution malt drink were acceptable in overall sensory characteristics among given
samples.
2022-07-01T00:00:00Z