Food Engineering
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Item Investigating the Effect of Gluten Content on the Pasting Properties of Wheat Obtained from Different Botanical Sources and Its Impact on Bread Quality(Addis Ababa University, 2024-09) Tigest Abera; Shimeles Shumi (PhD)Wheat is a cereal grain that comes in different varieties and is widely consumed worldwide. The objective of this study was to investigate the effect of gluten on functional and pasting properties of flour associated to its botanical sources. The study examined the proximate, functional, and pasting properties of three types of botanically varied wheat flours. Five wheat flour samples namely Arsi Wheat flour (AWF), Bale Wheat flour (BWF), Dodola Wheat flour (DWF), Mixed Wheat flour (MWF), and Supermarket Wheat flour (SWF) were developed and evaluated using the standard method. The study showed that the gluten content of DWF was 26.73 ± 0.23% on a wet basis which is the highest among the samples. Whereas, SWF has the lowest gluten content, i.e., 21.44±0.12%. On the other hand, the crude protein content of the BWF sample was found 12.620±0.05% showing the highest among all flour samples. Besides, the SWF sample showed higher water absorption capacity whereas MWF has highest water solubility. The pasting temperatures of AWF (89.1⁰C), BWF (87.25 ⁰C) and DWF (88.8 ⁰C) which was almost lied on similar ranges. However, the BWF sample has a significantly higher final viscosity than AWF and DWF at P< 5% level. It was observed that all wheat flour samples have similar functional groups such as hydroxyl groups (O-H), aliphatic hydrocarbons (C-H), carbonyl groups (C=O) from ketones or aldehydes, and ethers or esters (C-O). In terms of bread quality, bread baked from BWF sample has the best color, texture, taste, flavor, odor, mouth feel and overall acceptability. In addition, bread based on BWF sample got better protein content. The alkaline water retention capacity of the bread samples was decreased as the storage time increased in contrast, the staling rate of the bread samples was increased as the storage time increased. The study concluded that wheat botanical origin influences gluten content which in turn affect the dough properties (elasticity, heat tolerance, leavening) and bread quality (crust, color, sponginess).Item Development of Microencapsulated Product from Verbascum sinaiticum Leaf Extract for Antimicrobial Applications(Addis Ababa University, 2024-12) Alemu Belay; Shimelis Admassu (Prof.)Verbascum sinaiticum (V. sinaiticum), an Ethiopian medicinal plant, is rich in bioactive compounds, including antioxidants, antimicrobials, and anti-inflammatory agents. Traditionally used for treating infections, wound healing, and respiratory ailments, it also aids in food preservation by inhibiting spoilage microorganisms. In this study, V. sinaiticum was dried at 50, 60, and 70 °C in a fluidized bed dryer with a constant air velocity of 1.5 m/s. Five thin-layer drying models were evaluated using nonlinear regression analysis, with the Page model showing the best fit (R² = 0.9999, RMSE = 0.0036, SSE = 0.0001). Effective moisture diffusivity ranged from (2.135 ×10−10) to (5.895 × 10−10) m²/s, and activation energy values were 43.6 kJ/mol for unblanched and 41.6 kJ/mol for blanched samples. Blanching significantly reduced moisture content, impacting color and functional properties. UHPLC-ESI-QTOF-MS/MS analysis was employed to evaluate the effects of different drying methods on bioactive compounds in V. sinaiticum leaf extracts. Leaves were dried using oven (50, 60, 70 °C) and freeze dryers, and extracted with 50 %, 70 % aqueous ethanol, and 100 % water. Freeze drying with 70% ethanol produced the highest total phenolic content (TPC, 181.73 mg GAE/g) and total flavonoid content (TFC, 78.57 mg CE/g). TFC showed a strong correlation with DPPH radical scavenging activity (R² = 0.9082). FTIR analysis revealed reduced intensity of phenolic -OH groups in freeze-dried samples compared to oven-dried samples. Twenty-nine metabolites were identified, including 14 phenolic and flavonoid compounds, such as kaempferol, catechin, gallic acid, and myricetin derivatives, aligning with antioxidant activity results. Ultrasonic-assisted extraction (UAE) optimization yielded the highest TPC (179.8 mg GAE/g), TFC (64.49 mg CE/g), and antioxidant activities (DPPH: 61.85 μg/mL, ABTS: 38.89μg/mL) compared to maceration extraction. Optimal UAE parameters were extraction temperature (41.43 °C), sample-to-solvent ratio (36.32 g/mL), and extraction time (33.22min). Scanning electron microscopy revealed structural changes induced by UAE. Seventeen phenolic compounds were identified, confirming antioxidant capacities. Encapsulation of V. sinaiticum extract was studied using freeze-drying with maltodextrin (MD), gum arabic (GA), and a mixed matrix (MD:GA, 8:2). MD encapsulates showed superior water solubility (98.48 %), encapsulation efficiency (81.31 %), and phenolic stability (71.84 % retention at 4 °C over 32 days). XRD, FTIR, and SEM confirmed phenolic compound retention within microcapsules. Encapsulation masked unpleasant flavors and odors, enhancing the extract’s suitability for functional food applications. Encapsulated extracts demonstrated antimicrobial efficacy against Bacillus cereus, Escherichia coli, Candida albicans, Staphylococcus aureus with inhibition zones of 17–29 mm. Encapsulation improved thermal stability and reduced degradation temperatures. Encapsulated samples delayed microbial growth, maintaining an aerobic plate count of 2.94–3.01 Log CFU/g over 15 days at 4 °C, compared to 7.01 Log CFU/g in controls. Sensory evaluations confirmed the preservation of aroma and color during storage. This enhancement is attributed to the phenolic and flavonoid bioactive compounds, such as catechin, umbelliferone, kaempferol and myricetin derivatives, verbascoside, and proanthocyanidins, highlighting V. sinaiticum’s potential as a sustainable source of natural antimicrobial agents. These findings emphasize the potential of V. sinaiticum extract and encapsulated as a natural preservative for food, nutraceutical, and pharmaceutical applications.Item Characterization of Active Edible Packaging Film Based on Orange Fleshed Sweet Potato Starch and Moringa Stenopetala Leaf Extract(Addis Ababa University, 2024-09) Feben Girma; Shimelis Kebede (PhD)In order to maintain food quality and increase shelf life, food packaging is essential, and the rising demand for sustainable materials has spurred research into biopolymer-based active films. This study investigates the development and characterization of orange fleshed sweet potato starch based films incorporating Moringa stenopetala leaf extract. Commercial corn starch served as the control, while the orange fleshed sweet potato starch was extracted and modified through pre-gelatinization; a physical process of heating starch with water to break its structure, making it more easily dissolvable and absorbent, resulting in significantly higher (P < 0.05) swelling power, solubility, water binding capacity, and pasting clarity. X-ray diffraction patterns of native and pre-gelatinized orange fleshed sweet potato starches were similar (C-type) and chemical structures but the modified starch demonstrated superior thermal properties. A microwave-assisted extraction technique was used to maximize the Moringa stenopetala leaf extract, which was then added to the film, with response surface methodology used to optimize concentrations of modified starch, glycerol, and leaf extract to 4g, 40% w/w, and 1.5% w/w, respectively, for active bio-plastic film production. The tensile strength of the optimized film increased significantly from 7.06 MPa to 7.38 MPa, and its water vapor permeability improved to 3.145×10⁻⁹ g m⁻¹s⁻¹Pa⁻¹ compared to the pure film’s 3.225×10⁻⁹ g m⁻¹s⁻¹Pa⁻¹. It is important to remember that these comparisons are conducted at the same film thickness because differences in thickness can have an impact on both TS and WVP, which could compromise the comparison's accuracy. Moringa extract showed level of phenolic compounds of 8.56±0.04 mg GAE/g, a total flavonoid content of 9.38±0.26 mg QE/g, and a ferric reducing capacity of 8.72±0.08 mg AAE/g, while the active film contained 6.08±0.06 mg GAE/g phenolics, 6.30±0.21 mg QE/g flavonoids, and 3.18±0.04 mg AAE/g ferric reducing capacity. Antimicrobial testing revealed zone of inhibition values of 12.0±0.02 mm for MSLE and 9.2±0.42 mm for the active film against Staphylococcus aureus, and 9.0±0.48 mm for MSLE and 6.0±0.43 mm for the active film against Escherichia coli. The active films developed showed good antioxidant capacity, improved antibacterial activity, and biodegradability within 30 days. The study concludes that orange fleshed sweet potato starch films with moringa extract have promising potential for biodegradable packaging, offering reduced environmental impact and improved food safety.Item Starch and Flour Characterization of Indigenous Ethiopian Potato (Plectranthus Edulis) and Development of Gluten Free Functional Foodd(Addis Ababa University, 2025-01) Misikir Milkias; Shimelis Admassu (Prof.)This research aimed to explore the potential of Ethiopian potato (Plectranthus edulis) starch and flour, focusing on their physicochemical, structural, and functional properties. It also aimed to develop gluten-free functional food products and assess their quality for broader industrial applications. The study investigated multiple aspects, including starch isolation, flour processing, modification techniques, and the development of nutrient-dense, gluten-free noodles suitable for celiac patients. The findings provide critical insights into optimizing starch extraction, modification, and usage in advanced food processing and product development. The physicochemical, functional, and structural properties of starches isolated from two Ethiopian potato ecotypes (Chanqua and Loffo) using three different methods—distilled water (DW), sodium metabisulfite (SMS), and sodium chloride (NaCl)—were assessed. The study revealed significant differences in starch yield, with Chanqua yielding the lowest starch using DW (97.4%) and Loffo yielding the highest using SMS (99.3%). In terms of color, Loffo starches exhibited higher lightness (L*) and whiteness values, with NaCl and SMS isolation yielding superior results. Proximate composition, including moisture, protein, ash, fat, crude fiber, and carbohydrate content, showed variation across the ecotypes and isolation methods. Structural analysis using X-ray diffraction (XRD) revealed B-type diffraction patterns, while FTIR analysis indicated structural changes depending on both ecotype and isolation method. SMS was found to be the most effective isolation method for acquiring high-quality starch, particularly for the Loffo ecotype, with higher crystallinity and better functional properties. The next phase of the study focused on the effects of isolation media on starch granule morphology, powder flow properties, and functional characteristics such as pasting and thermal properties. Scanning Electron Microscopy (SEM) revealed that starch granules were predominantly spherical and elliptical, with no significant differences across isolation methods. Flow properties varied significantly, with porosity ranging from 27.16% to 40.72%, Hausner’s ratio from 1.04 to 1.20, and the angle of repose from 23.00° to 36.33°. Sodium chloride (CNaCl) had the highest peak viscosity (8979.02 mPa.s) and final viscosity (5936.03 mPa.s), making it superior for thickening applications. Thermal properties were also affected by the isolation methods, with gelatinization onset (To) ranging from 65.20°C to 68.80°C and conclusion (Tc) temperatures between 80.06°C and 84.14°C. Sodium metabisulfite (SMS) isolation produced starches with better flowability, thermal stability, and overall gelling potential, suggesting its suitability for both food and industrial applications. A comparison of Ethiopian potato flour from Chanqua and Loffo varieties with wheat flour (WF) followed, examining the effects of drying methods—oven drying and sun drying—on their physicochemical, structural, and functional properties. Moisture content (MC) ranged from 5.72% for oven-dried Chanqua Ethiopian potato flour (OD-CEPF) to 7.53% for sun-dried Loffo Ethiopian potato flour (SD-LEPF). LEPF demonstrated superior flow properties, with a lower Hausner ratio (1.16) and Carr’s index (CI) (14.51%), compared to CEPF. Significant differences were found in water absorption capacity (WAC), oil absorption capacity (OAC), and swelling power (SP), with LEPF outperforming CEPF in all aspects. Oven drying enhanced the physicochemical properties of flour, with XRD analysis confirming a B-type diffraction pattern and FTIR showing significant structural differences. These findings suggest that LEPF, particularly when oven-dried, has great potential for food applications due to its superior functional properties compared to wheat flour. The research also addressed the knowledge gap regarding moisture sorption isotherms and rheological properties of Ethiopian potato starch and flour. Sorption isotherms were determined at 20°C, with equilibrium moisture content (EMC) plotted against water activity (aw). The modified GAB and BET models best described the sorption behavior, with higher monolayer moisture content observed in flour due to its higher protein and fiber content. Rheological analysis revealed pseudoplastic behavior for both starch and flour, with flow index values (n) below 1. The Power-law model provided the best fit for starch, while the Prandtl-Eyring model was most suitable for flour. Dynamic frequency sweep tests indicated higher storage modulus (G') than loss modulus (G''), implying elastic dominance. Complex viscosity values were 289.92 Pa.s for starch and 346.24 Pa.s for flour, with lower tan δ values in starch indicating a stronger elastic response. These findings provide valuable insights for food processing and storage, particularly in the handling of Ethiopian potato starch and flour. The effects of heat moisture treatment (HMT) on the physicochemical, morphological, and functional properties of Ethiopian potato starch and flour were also studied. HMT significantly affected the color of both starch and flour, with a reduction in lightness (L*) values due to Maillard reactions. The amylose content increased from 23.02% in untreated starch to 23.95% in HMT-treated starch (HMTS-30), while crystallinity was reduced by 1.99% for starch and 2.62% for flour. FTIR spectroscopy confirmed the retention of structural integrity after HMT, while pasting properties showed reduced viscosity, with peak viscosity declining from 8346.15 mPa.s in native starch to 3950.79 mPa.s in HMTS-30. Thermal properties were similarly affected, with higher gelatinization temperatures and stability noted in HMT-treated samples. These findings highlight the potential of HMT-modified starch and flour for industrial applications, particularly where resistant starch with enhanced stability is required. Lastly, gluten-free noodles were developed using Ethiopian potato starch, resistant starch, and flour, fortified with egg white protein (EWP) and carboxymethyl cellulose (CMC). Noodles made from starch-based formulations exhibited better cooking properties, with swelling index (SI) values ranging from 2.31 to 2.79 and lower cooking loss (CL) compared to flour-based noodles, which had SI values of 1.63 to 1.94. Protein content ranged from 12.46% to 15.17% in flour-based noodles, while starch-based noodles had lower protein content. Texture profile analysis revealed significant differences in firmness, with higher values correlating to better sensory acceptance. Sensory evaluations showed favorable attributes for both flour and starch-based noodles, with hedonic scores exceeding six on a nine-point scale. These findings suggest that Ethiopian potato starch and flour, particularly when fortified with resistant starch and EWP, can be used to produce gluten-free noodles with improved texture, nutritional quality, and consumer acceptability. In conclusion, this study demonstrates the versatility of Ethiopian potato starch and flour, highlighting their potential for use in various food and industrial applications. The research provides comprehensive data on starch isolation, modification, and flour processing, paving the way for the development of functional food products, such as gluten-free noodles, that meet the growing demand for healthier and alternative food products.Item Valorization of Low-Valued Ray-Finned Fish (Labeobarbus nedgia) Through Enzymatic and Sub-Critical Water Hydrolysis: Green Advanced Processing Technologies to Obtain Protein Hydrolysates for Use as Functional Foods(Addis Ababa University, 2025-01) Solomon Abebaw; Shimelis Admassu (Prof.)The global demand for sustainable utilization of fish resources, including low-valued and discarded species, has increased due to environmental concerns. Fisheries worldwide face challenges with by-catch, resulting in significant discards of non-commercial species annually. In African contexts like Ethiopia, by-catch management differs, contributing to environmental pollution. While the inefficient resource utilization and environmental impact from discarded fish are significant concerns, another critical issue facing society is the recent global increase in noncommunicable diseases. This growing health crisis underscores the need for foods with health benefits, which can play a crucial role in preventing and managing these conditions. Labeobarbus (LB) spp., non-commercial fish and discarded due to the presence of small bones that are difficult for consumption, possess unused nutritional and functional potential. Therefore, this research aimed to valorize the low-valued LB by employing integrated concept of valorization, advanced processing technologies and green chemistry, thereby reducing waste and enhancing resource efficiency in fisheries management, as well as enabling the production of health beneficial ingredients. In the first finding of this research, the potential of enzymatic hydrolysis for producing protein hydrolysates from LB muscle was studied. Primary, three commercial enzymes, namely Alcalase®, Novozym®, and Protease®, were tested for their potential to hydrolyze the muscle protein of LB at a temperature of 60 oC, pH 8, 10 % (w/v) of substrate loading, and enzyme to LB ratio of 2 % (v/w). The highest hydrolysis degree (DH) was found for protein hydrolysate prepared using Alcalase® (18.4 %) followed by Novozym® (17.2 %) and Protease (15.3 %). Based on this result, Alcalase® and Novozym® were selected to study the effects of enzyme to LB ratio (0 - 3 %, v/w) and hydrolysis temperature (50 – 70 ºC) on free amino acid content, antioxidant capacity and physicochemical characteristics of hydrolysates. The maximum DH (21.8 %) was achieved after hydrolysis of LB for 4 h using Alcalase® at an enzyme-to-LB ratio of 3 % (v/w) and temperature of 60 oC that also corresponded with the highest total free amino acid content (TFAA), antioxidant activity. The kinetic data exhibited a strong fit with the three-parameter Weibull model. The other advanced processing technology investigated as a potential green hydrolysis method for the valorization of LB was subcritical water hydrolysis (SCW) method. Protein hydrolysates were prepared using CO2 and N2 as pressurization agents at different temperatures (140 - 200 °C). The DH and TFAA content of LB muscle protein hydrolysates increased with increasing temperature for both pressurizing agents. Using CO2 as a pressurizing agent at 200 °C resulted in the highest DH (54.5 ± 0.4%) and TFAA content (210 ± 1 mg/gprot). Likewise, the properties of LB skin hydrolysates were significantly influenced by the hydrolysis temperature. The trend of the hydrolysis kinetics of LB skin hydrolysates were similar with the muscle hydrolysates, but the DH of the skin hydrolysates at the final hydrolysis time were significantly lower than the muscle hydrolysates at each hydrolysis temperature studied. The highest DH, 35.7 ± 1.3%, of LB skin hydrolysate was observed at 200 °C. Predominantly, glycine was released in protein hydrolysates from both protein sources (muscle and skin). The antioxidant activity of both muscle and skin hydrolysates, assessed through three different assays, increased with temperature and reached its peak at 200 °C for LB muscle. At the end, four different hydrolysates prepared from the muscle and skin of LB using both hydrolysis technologies at their optimum conditions were subjected to a comparative study on their physicochemical and functional characteristics, as well as antioxidant stability. Accordingly, SCW hydrolysis resulted in significantly higher DH, hydrolysis yield, antioxidant capacity, and free amino acid content than enzymatic hydrolysates. However, enzymatic hydrolysates generally exhibited better functional properties than SCW hydrolysates. Additionally, muscle hydrolysates showed superior physicochemical, antioxidant, and functional properties compared to skin hydrolysates. Furthermore, various food processing conditions, salt, metal ions, and simulated gastrointestinal (GI) digestion significantly impacted the antioxidant stability of the hydrolysates. Generally, enzymatic hydrolysates presented better antioxidant stability than SCW hydrolysates. This research demonstrated the effectiveness of enzymatic and sub-critical water hydrolysis as green and sustainable technologies for valorizing low-valued Labeobarbus fish into high-value protein hydrolysates. These hydrolysates exhibited good physicochemical, functional, and bioactive properties, making them suitable for use as functional food ingredients. SCW hydrolysis, with CO2 as a pressurization agent, exhibited to be a good alternative to the expensive enzymatic methods, producing hydrolysates with higher antioxidant activity, free amino acid profiles, and improved physicochemical qualities. However, additional research is needed to enhance the antioxidant stability of SCW-derived hydrolysates and to explore their applications in functional foods, assessing their performance and stability under real-world conditionsItem Comprehensive Investigation of Borde, an Ethiopian Traditional Cereal-Based Beverage: Characterization, Probiotic Strain Isolation, and Functional Beverage Development for Antiobesity(Addis Ababa University, 2025-01) Tuaumelsan Shumye; Shimelis Admassu (Prof.)Ethiopia has a long-standing tradition of producing and consuming cereal-based beverages. One of the most popular traditional drinks is borde, which undergoes spontaneous fermentation using grains such as sorghum, maize, wheat, barley, millet, and their malts. However, this natural fermentation process poses challenges in terms of predictability, control, and quality. Undesirable outcomes like slow or incomplete fermentation, off flavors, short shelf life, and inconsistent quality can occur. Therefore, the main task of this work is to comprehensively study borde production. Various aspects including traditional processing techniques, microbiology, antioxidant properties, functionality, rheology, physicochemical characteristics, probiotic potential, identification of metabolites, and evaluation of effectiveness using the C. elegans model were investigated. Borde samples were collected from Addis Ababa (AA), Wolayita Sodo (WS), and Arba Minch (AM), Ethiopia, chosen based on their relevance to production, accessibility, and suitability for sample collection. The average physicochemical parameters of the borde samples included total acidity (TA) of 0.63 (g/100g), alcohol content of 3.26 %, pH of 4.04 and electrical conductivity of 0.78 ms/cm. The early stages of fermentation exhibited prevalence of enterobacteriaceae and aerobic mesophilic bacteria. Towards the end of fermentation, yeast and LAB dominated the microbiological profile of all borde samples. Antioxidant activities, assessed through DPPH and ABTS values, ranged between 51.5–64.6% and 47.4–62.9.1%, respectively. The average value of α-glucosidase and pancreatic lipase inhibition for borde samples were ranged from 36.56 – 43.23 % and 31.08 – 40.19 %, respectively. Rheological investigations indicated pseudoplastic fluid behavior, as evidenced by the decreasing viscosity values with shear rate. Eleven LAB and thirteen yeast strains were selected based on their bile salt hydrolase (BSH) activity and evaluate their cholesterol lowering ability and antioxidant activities. The results showed that LAB strains exhibited a strong potential to lower cholesterol (85-90%), while yeast strains showed the highest cholesterol removal (82-89%). All strains demonstrated strong antioxidant activity and survived simulated gastrointestinal tract (GIT) conditions. LAB and yeast isolates were selected as the most promising probiotics based on their ability to resist simulated GIT environments. Safety evaluation revealed that none of the strains exhibited undesirable hemolytic activity or mucin hydrolysis. LAB strains were not resistant to most tested antibiotics except for vancomycin, gentamycin, and streptomycin, whereas yeast isolates were resistant to all antibiotics. The LAB strains were identified as Pediococcus acidilactici, while, yeast isolates were identified as Saccharomyces cerevisiae, and Pichia cecembensis. The probiotic strains, Pediococcus acidilactici WS07 and Saccharomyces cerevisiae AM18 was used singly and in co-culture to ferment a cereal-based substrates. The viability of every tested strain remained higher than 7 log CFU/mL, satisfying the requirements suggested for probiotic food items. The formation of organic acids is what caused the pH to decrease from roughly 6.6 to 3.8, yet this had no effect on the viability of the microorganisms. A total of 25 volatile substances, such as aldehydes, alcohols, esters, acids, ketones, and other substances, were found. The extracts from fermented cereals were comprehensively assessed for antioxidant activity, pancreatic lipase and α-glucosidase inhibition, UHPLC-Q-TOF-MS/MS metabolite identification, and in vivo efficacy using the C. elegans model. The findings highlight the remarkable improvements in metabolites and fat-reducing effects of the extracts from fermented cereals, presenting encouraging avenues for anti-obesity research. Notably, the fermented sorghum extracts improved lipase (88.23%), α-glucosidase (85.62%), DPPH (71.86%), and ABTS (59.92%) inhibitory activities compared to unfermented sorghum extract. All fermented extracts displayed strong antioxidant properties, as shown by increased DPPH (67.77–71.86%) and ABTS (59.91–65.49%) scavenging activities. The study further unveiled substantial increases in total polyphenols, flavonoid contents, and individual polyphenols following fermentation. Untargeted metabolite profiling using UHPLC-Q-TOF-MS/MS demonstrated significant changes in the metabolite composition of fermented samples. Additionally, supplementing C. elegans with fermented extracts resulted in an extended lifespan, reduced lipid content, and diminished triglycerides, indicating potential health benefits. This research emphasizes the potential of P. acidilactici WS07-fermented sorghum and sorghum-maize extracts as valuable resources for the development of functional foods with enhanced antioxidant and anti-obesity properties. The study contributes valuable insights into the bioconversion of cereals through microbial fermentation, showcasing their potential for promoting health and combating obesity.Item Anchote (Coccinia abyssinica (Lam.) Cogn) Starch and Flour Modification Using Hydrothermal Treatments and Valorization as Functional Ingredients in the Development of Food Products(Addis Ababa University, 2024-06) Yohannes Toles; Shimelis Admassu (Prof.)Anchote (Coccinia abyssinica (Lam.) Cogn) is an underutilized root and tuber crop indigenous to Ethiopia and potentially an important source of starch. The native users cultivate anchote for its medicinal, economic, nutritional, and socio-cultural benefits. The anchote tuber has a significant number of beneficial nutrients, such as carbohydrates, protein, fat, fiber, and different minerals. Compared to other root and tuber crops, this crop is renowned for its vital protein and calcium content. Anchote tubers have a high starch content (75–79%), making them a suitable alternative source of starch for use in several industrial applications. However, understanding the physicochemical properties of starch generated from such underutilized roots and tubers is critical in order to develop unique value-added products. The quality of starch is determined by its physicochemical properties, which include its morphology, particle size, amylose content, crystallinity, thermal properties, and swelling powers. However, there is still a dearth of studies on important anchote starch properties from different genotypes: the rheological properties of anchote starch gels, intrinsic characteristics like storage texture kinetics, and the effect of starch concentration on the gel rheological properties of anchote starch gels, which are so important for their food applications. Thus, this study examines the properties of native and hydrothermally modified starches from four anchote tuber cultivars and compares them to potato and cassava starches. It also investigates the effects of hydrothermal modifications on the pasting, morphological, and thermal properties of anchote flour-starch mix. The study also examines the impact of partial replacement of gluten-free teff flour with modified anchote flour-starch mixes on gluten-free biscuits. The granule sizes of the anchote cultivars varied, but they all exhibited a B-type crystalline structure similar to that of potato starch. The amylose content of anchote starches ranged from 15.8–22.3%. The phosphorus in anchote starches ranged from 82 to 93 mg/100 g, which is much higher than that of potatoes and cassava (60.3 and 5.8 mg/100 g, respectively). This high phosphorus content influences the functional properties of anchote starches, making them well-suited for use in various types of noodles, glucose syrups, and viscous products. Anchote starches had a significantly different gelatinization temperature and enthalpy than potato and cassava starches, ranging from 60.97 to 69.33 °C and 16.87 to 18.38 J/g. Significant differences were also noticed in the pasting properties of anchote cultivar starches. In comparison to potato and cassava, they demonstrated greater stability to heating and shearing, with higher trough viscosity (TV) (2046 to 2280 mPa·s), lower breakdown viscosity (BV) (248 to 487 mPa·s), and a higher final viscosity (FV) (3409 to 3686 mPa·s). These properties are significant in the food processing industry and when high gel viscosity is needed after cooling. In comparison to cassava and potato gels, anchote starch gels displayed considerably greater viscoelastic moduli and much lower (tan δ)1 values. These rheological features are typical of true gels. According to the present findings, anchote starch had acceptable color characteristics that were similar to those of potato and cassava starches. The anchote starch exhibited lightness (L*) and whiteness values above 95 across different cultivars. As the cooking temperature increased from 40 - 90 °C, the swelling power (SP) and water solubility index (WSI) of anchote starches demonstrated a clear rise. It's important to note that the rate of increase differed significantly from that of the control starches, with anchote starches showing a lower increase compared to potato starches and cassava starch in the following order: anchote starches < potato starches < cassava starch. Compared to potato (PS) and cassava (CS) starch gels, anchote starch gels had lower (tan δ)1 values and demonstrated better elasticity, withstanding higher stresses before breaking their structure. In addition, they were more stable at higher concentrations and exhibited higher viscoelastic moduli even at lower concentrations than the PS and CS gels. The study of the textural evolution of the gels over storage revealed that anchote starch gels were less adhesive than PS gel and had initial and final hardness that was significantly higher (≥40%) after 192 hours. The hydrothermal treatments (ANN and HMT) significantly altered the pasting characteristics of anchote starches. The pasting properties (PV, TV, and BV) were decreased significantly after HMT and ANN treatment. HMT significantly reduced the PV of anchote starches compared to ANN treatment. The lower BV values obtained in all studied cultivars show the higher stability of modified anchote starches to thermal treatment and mechanical shearing. The ANN treatment significantly (p < 0.05) increased the final viscosity (FV) compared to HMT and native anchote starches. The rheological property shows the dominance of the elastic over the viscous behavior, having higher G′ values than G″ in the entire frequency range for all studied starch gels. The G′, G′′, and (tan δ)1 values were significantly decreased upon HMT treatment, while ANN treatment significantly increased the G′ and G′′ of anchote starches related to the native starches. Both HMT and ANN increased gelatinization temperatures and decreased enthalpy in all cultivars studied. The study found that the B-type structure of anchote starches remained unchanged after hydrothermal treatments. However, ANN and HMT treated anchote starches had higher relative crystallinity compared to native starches. These results showed that ANN and HMT treatments efficiently modified the rheological, pasting, and thermal properties of anchote starches isolated from four cultivars. The hydrothermal treatments significantly (p < 0.05) affected the pasting properties of anchote flour (DF) and anchote flour-starch mix (DFS). The PV and BV of DF and DFS anchote samples were decreased upon ANN and HMT treatment. The addition of anchote starch to anchote flour significantly improved color characteristics, and carbohydrate contents in both native and hydrothermally modified samples. The study showed that HMT and ANN treatment significantly (p < 0.05) reduced the phytate, tannin, and total phenol contents in both DF and DFS, while the HMT treated samples had the lowest phytate contents compared to ANN and native samples. Likewise, the study showed that the hydrothermal treatments significantly affected the hydration properties (WAC, OAC, SP, and WSI) of studied DF and DFS. The HMT and ANN treatments did not affect the FTIR spectra of studied anchote samples. However, hydrothermal treatments raised the gelatinization temperatures (TO, TP, and TC) of DF and DFS. The results revealed that hydrothermal treatments enhanced the thermal stability of DF and DFS samples. As a result, it appears that the HMT and ANN anchote flours would be appropriate for applications requiring heat stability. The growing consumer demand for gluten-free food products has led to an increased need for innovative gluten-free ingredients that offer improved nutritional benefits. Thus, this study examines the impact of the partial replacement of gluten-free teff flour (TF) by modified anchote flour-starch mixes (HMT-DFS and ANN-DFS) on the physical, nutritional and sensory characteristics of gluten-free biscuits. The result showed that the color, proximate compositions, pasting, and functional characteristics of the gluten-free flours used in this study varied significantly (p < 0.05). HMT-DFS and ANN-DFS flours had higher L*, a*, b*, and whiteness values compared to TF flour. The protein contents of gluten-free HMT-DFS and ANN-DFS flours were almost similar, while those of TF flour had a slightly higher protein content. But HMT-DFS and ANN-DFS had significantly higher ash contents and lower fat and fiber contents compared to TF. The pasting properties of the studied flour samples varied significantly (p < 0.05). The lowest BV value of the ANN-DFS and HMT-DFS samples shows that they have the highest stability to thermal treatment and mechanical shearing; thus, these samples are ideal functional ingredients in formulations of food products that require higher thermal treatments. The study showed that substituting gluten-free HMT-DFS and ANN-DFS flours for teff flour did not affect biscuit thickness, but slightly increased spread ratio. However, the inclusion of HMT-DFS and ANN-DFS significantly influenced color features. The study also found that incorporating anchote flour-starch mix into teff flour significantly affected color characteristics at higher substitution levels. The study found that gluten-free biscuits AB10, AB20, HB10, and HB20 had superior physical and sensory properties compared to control biscuits. These biscuits had higher ash, fat, and fiber contents than the control WB biscuits and comparable values with the control TB biscuits. The study also found that incorporating a modified anchote flour-starch mix in gluten-free teff flour biscuits enhanced proteins, carbohydrates, energy values, and mineral contents, making it a useful functional ingredient for gluten-free formulations. Therefore, the present findings showed that the hopeful potential utilizations of modified anchote flour and starches as functional ingredients in food processing, product development, novel food product formulations, and additional industrial applications.Item Characterization of Heat-Moisture Treared Starch from Locally Produced V. Faba for The Improvement of Freeze-Thaw stability of “Siljo” Paste(Addis Ababa University, 2011-06) Abebe Moges; Shimelis Admassu (PhD)Functional properties of granular and heat moisture treated (HMT) starches isolated from locally grown V. faba CS-20-DK variety were studied for their effect on the freeze-thaw stability of Siljo paste. Faba bean grain was dehulled, milled, sieved and fractionated into, course (>125μm), medium (80-125μm), and fine (< 80μm) size flour particles. Flour fractionates were slurred in a tap water and separated into supernatant and primary starch residue (PSR) using batch centrifuge. Sieving into fine flour particle resulted in higher carbohydrate (79.36%), lower protein, fat, ash, and fiber distribution, and highest starch yield (52.76%) and least nitrogen (0.08%) and ash (0.05%) contents in the total solids of PSR. Starch yield is comparable with 37% yield from horsebean flour obtained by Kawamura et al (1955) method. The starch obtained from fine flour fractionate was subjected into HMT at 19%; 23%; and 27% (d.b) moisture levels, treated in a hot air oven at 1000C for 16hr, and then dried and milled. The effect of temperature on hydration properties and least gellation concentration (LGC) were determined as a measure of water retention capacity of retrograded starch of granular and HMT starch was investigated. Hydrothermal conditioning led to restricted swelling power (SP) and significant increase in water solubility (WS) and water absorption index (WAI) with the level of conditioning moisture. In all investigations highest SP, WS, and WAI of starches in the temperature range of 85-950C suggests that water penetration into the granules can be achieved at elevated temperature. HMT resulted in increase hydrophilic tendency and conversely decreased the hydrophobic tendency. Except HMT19%; LGC of all HMT starches progressively decreased with the increase in conditioning moisture level. Percentage of retrogradation was decreased after HMT. Degree of retrogradation between the 1st and the 4th days starch gels storage was investigated in the range 100-100% (granular); 85-100% (HMT19%); 52-89% (HMT23%); and 48-84% (HMT27%). The effect of partial substitution of HMT starch at various concentrations (9%, 23%, and 38%) on the freeze-thaw stability (% syneresis) of Siljo paste was evaluated. The highest and the least percentage of syneresis were 167% for normal flour and 73% for the 37.5% HMT27% substituted flour. The incorporation of HMT starch resulted in improved resistance of Siljo paste against the re-crystallization process upon cooling. Application of HMT starch is recommended for the production of sauces and soups with a better stability at ambient or refrigerated storage conditionsItem Development and Characterization of Papaya Based Fruit Leather Supplemented with Orange-Fleshed Sweet Potato and Haricoat Bean Flour(Addis Ababa University, 2023-02) Eftu Tesfaye; Solomon Kiros (PhD)The goal of this study was to investigate the production of nutritional fruit leather using haricot bean and orange fleshed sweet potato flours to partially substitute papaya pulp. The study examined β-Carotene content, functional property, anti-nutrient composition, and physicochemical properties, proximate composition of the raw materials and composite pulps, additional to this mineral and microbiological analysis, texture and color analysis, and finally sensory characteristics of the fruit leather were analyzed using standard methods. The formulation for composite flour was developed using a D-optimal mixture design ratio applying Design-Expert®, version 13. Accordingly, 11 composite pulp samples were developed (R1, R2……. R16) and the data analyzed using mini-tab software, the result was evaluated by used one-way analysis of variance (ANOVA) and test of significant (p<0.05).The composite puree samples are significantly different each other at (p<0.05) with increasing haricot bean and orange fleshed sweet potato flour ratios on papaya puree. the optimum fruit leather at run(sample) 11 was made with 60.02% papaya pulp, 19.98% haricot bean, and 20.00% orange-fleshed sweet potato flour showed significantly higher values of β-carotene (746 μg/g), protein (12.05%), fiber (5.32%), and fat (4.09%), and a moisture content (15%) than the control fruit leather(100%papaya pulp),Moreover the texture analysis result of the fruit leather indicated that the hardness, chewiness, and fracturability decreased with the increased amount of haricot bean and orange-fleshed sweet potato flours. The mineral contents of the fruit leathers ranged from Ca 5.37 to 21.49, Mg 11.49 to 22.49, Na 7.88 to 24.20, K 29 to 24.50 mg, Fe 0.13 to 1.72 (mg/100 kg), and Cu, Mn, and Zn were also detected in the zero range In terms of all the sensory parameters except taste and mouth-feel, the optimum fruit leather showed significantly higher scores than the control fruit leather. Generally the results showed that the supplementing of haricot bean and orange fleshed sweet potato flour to papaya puree improved the nutritional quality of the fruit leather.Item Comprehensive Study on Oil Extraction from Papaya (Carica) Seed and Analysis of its Characteristics, Bioactive Components and Antimicrobial Properties(Addis Ababa University, 2024-03) Mekdes Amare; Shimelis Admassu (Prof.)The utilization of whole fruits and vegetables, including the typically discarded parts during food processing, presents an opportunity to reduce agro-industrial waste. This study focused on evaluating the proximate and nutritional potential of Carica papaya seeds and its oil. The oil from papaya seeds was characterized, and the effects of operating parameters (moisture content, temperature and heating time) on oil yield were investigated using a screw expeller. The Box-Behnken design was utilized for the experimental design, and response surface methodology was used to assess the effects and significance of the models on the response variable (oil yield). The maximum extraction efficiency 24.248%. achieved with a moisture content of 6.32 %, heating time of 9.82 minutes, and temperature of 69.54℃. Furthermore, the byproducts obtained from the screw press meal and cake underwent oil recovery through Soxhlet extraction, and the effects of moisture content, particle size, and extraction time were evaluated. Moreover, Physical and chemical properties of the oil also evaluated. Despite the growing interest in papaya seed oil, there is a lack of comprehensive research on its bioactive components and antimicrobial properties. Gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared (FTIR) analysis were employed to identify these components and functional groups for different extraction methods and also Total Phenolic content and Flavonoid content, were determined using standard methods. The results showed an average total Phenolic content of 19.41 ± 1.33 mg GAE/ml of sample and 2.25 ± 0.787 mg QE/g Total Flavonoid content. Antimicrobial properties were assessed using the agar diffusion method, and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined through broth dilution methods. The oils exhibited effectiveness against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli. MIC values ranged from 3.125 to 12.5 μl/ml, while MBCs varied from 6.25 to 50 μl/ml.Item Development and Quality Assessment of Nutritionally Enriched Texturized Soya Protein with Ground Flaxseed Flour(Addis Ababa University, 2024-03) Memiru Michael; Kumsa Delessa (PhD)Texturized soya protein is one of the most important meat alternative product among plant proteins. Texturized Soya protein is currently limited to soyabean and cereal in many countries. Whole soyabean and flaxseed were cleaned, milled and defated. The soybean and flaxseed flour were blended using Response(Box-Bhnken) design to formulate composite flour with the ratio of 90%,85%,80% and 10%, 15%,20% respectively where as 120 oc,135oc,140oc, 145oc, 150oc and 60oc, 70oc, 80oc were used for baking and drying respectively. The data generated were statistically analyzed by general linear model analysis of variance using the Minitab software program version 18. Functional properties and proximate analysis were carried out on the flour and texturized Soya protein sample, the result indicated that , fiber,ash ,carbohydrate,moisture value of composite flour increased with the increase in blend proportion (p<0.05) the bulk density,water absorbition capacity,oil absorbition capacity were observed with an increase in flaxseed flour proportion in the composite flour. The mineral content (Fe,Zn,K,Mn,) of texturized Soya protein were improved by the presence of flaxseed flour. Significant difference(p<0.05) in sensory quality of Texturized Soyaprotein with an increase in flaxseed flour was observed. the result of optimization confirmed that texturized soya protein which was dried with drying temperature 60 oc, drying time 24.087 min and blending ratio 20% flaxseed flour with response of moisture content of 8.69,flavor 7.59, overall acceptability 7.64 was selected. it was concluded as the increseang of ground flaxseed flour had increased sensory, proximate,functional properties and mineral content of texturized soya protein.Item Effects of Storage Duration and Temperature on Physicochemical Properties of Goat Meat.(2023-07) Merkebu Sefefe; Kumsa Delessa (PhD)For eons, the production and consumption of meat have been integral parts of our societies. Since it spoils easily, research is constantly being done to find ways to keep it fresher for longer than is currently the case. By analyzing the impact of storage temperature and time on the physicochemical characteristics (pH, tenderness, water holding capacity, and glycogen content) of goat meat, this study advances this effort. The goat meat used in this study was purchased from Queens Super Market in Addis Ababa, and a normal protocol was followed for the physicochemical examination. The physicochemical qualities were analyzed using storage temperatures of -4, 25, 35, and 50°C for a duration of 12 hours. Throughout the course of the storage, samples for the analyses were taken every two hours from the goat meat that was kept at the aforementioned temperatures. The findings of the analysis revealed that there were notable variations (P<0.05) in the samples' physicochemical characteristics over the course of storage. In comparison to other storage temperatures, samples kept at 50 °C for 12 hours showed decreased pH, water holding capacity, and glycogen level. Tenderness increased as the storage temperature rose from -40°C to 50°C, while the water-holding capacity, pH, and glycogen content declined. The protein and fat contents of goat meat stored at a temperature of -4°C and time of 12 h were determined, and the average values were observed to 21.218 and 3.236% for protein and fat respectively. Storage temperature of 25 °C and storage duration of 8 h was selected as optimal condition for storing goat meat. Selection of this optimal condition was done based on the values of water holding capacity, pH, glycogen level and tenderness obtained during the optimization.Item Effects of Roasting Degree on Coffee Quality and Its Compositional Attributes(Addis Ababa University, 2023-10) Amanuel Getachew; Shimeles Shumi (PhD)Coffee is one of the preferable drinkable beverages in the worldwide. However, its palatable acceptability by consumers depends on the degree of roasting quality of the coffee bean regardless of the varaity. The objective of this research was to evaluate the effects of roasting degree on coffee Quality and compositional attributes. Samples of Harar coffee beans whose speciality graded were selected and subjected to 190 to 230°C roasting degree for 5 to 12 minutes using drum roaster. Where the roasting color intensity classified as light(M), Light medium(LM), Medium(M), Medium Dark(MD) and dark degree(DM) of roasts from 190°C - 230°C for 5 to 12 minutes, though the coffee beans have significant changes in physical and chemical properties at different degree of roasting temprature. The result also showed that the volume change and the weight loss by the roasted beans during different types of roasting degree. The roasted coffee beans were grinded and its proximate composition, sensory quality and cupping were evaluated. The result showed that, medium of roasted coffee beans the amount of caffeine, CHO, crude fat, crude fibber, ash content, and moisture content present in harar coffee were evaluated 2.02, 46.2, 14.41, 18.08, 3.31and 2.15 respectively. And the body of coffee at L, LM, M, MD, D roast degree were 6.08, 7.00, 8.58, 8.5 and 6.42 respectively. The roasted coffee beans were evaluated for cup quality at Light, Light medium, medium, medium dark and dark degree of roast by three professional cuppers. Based on cupping evaluation, dark and light roasting degree resulted at the least total cup score for all the coffee roasting degree. Cup quality were evaluated by a team of certified panelists at Great Abyssinia coffee processing and quality analysis laboratory. Effects of roasting temperature and time were significant (P<0.05) on cup quality parameters. The highest values of fragrances, Flavor, Aftertaste, Acidity, Body, Uniformity, Balance, Clean cup, Sweetness and overall acceptability were 8.83, 9.17, 8.83, 8.75, 8.58, 8.25, 8.5, 8.92, 8.33 and 8.83 respectively. According to the cup test result the values of overall quality showed that, all tested samples varied between commercially acceptable and highly acceptable. Highly acceptable values in most cup quality attributes were 87 % to treatments of 210°C for 8 minuteItem A Study on The Flour Properties and Qualities of Wheat-Based Biscuits Supplemented with Faba-Bean and Cassava Flour(Addis Ababa University, 2023-09) Gebremedhn Brhane; Shmeles Shumi (PhD)Faba beans and other legumes are significant due to their high nutritional value. The goal of this study is to investigate on the flour properties and qualities of wheat-based biscuits supplemented with faba-bean and cassava flour. The study examined the proximate composition of both (composite flour and biscuit flour), rheological, and functional properties. Besides mineral content, total energy, gluten content, texture, color attribute, and sensory evaluation have been studied. The formulation for composite flour was developed using a D-optimal mixture design ratio applying Design-Expert®, version 13. Accordingly, 16 composite flour samples were developed (T1, T2……. T16 and control sample) and evaluated using the standard method. The gluten content of wheat flour was significantly different from the whole formulated composite flour and also the samples were significantly different from each other at (p<0.05). The proximate composition shows that the crude protein content of faba-bean flour (23.13±0.00%) is two times more than that of wheat flour (11.75±0.00%) and eight times more than that of cassava flour (2.9±0.02%), respectively. Whereas, composite flours show lower water absorption capacity and higher oil absorption capacity and water solubility than wheat flour. The result showed that the pasting temperature range was 72.55 to 76.70 °C compared with the pasting temperature of the control sample (89.65 °C). Moreover, biscuit developed from 40.5% wheat flour, 40% cassava flour and 19.5% faba-bean flour biscuit looked almost similar to the wheat flour biscuit in all aspect with overall acceptability of 8.05±0.64. In this study the 40.5% wheat flour, 40% cassava flour and 19.5% faba-bean flour biscuit was found to be the most acceptable biscuit and had high crude protein, crude fiber and low gluten content. On the other hand, adding faba-bean flour to wheat-cassava flour positively affects the physical, chemical, color attribute, texture, alkaline water retention capacity, staling rate and sensory characteristics of the biscuits.Item Development of Cellulose Nanocrystal Reinforced Anchote (Coccinia abyssinica) Starch Based Antimicrobial Food Packaging Film(Addis Ababa University, 2023-11) Habtamu Shebabaw (PhD); Anuradha Jabasingh (Assoc. Prof); Shegaw Ahmed (Asst. Prof.)Food packaging is a critical component of the food supply chain, providing protection from contamination, spoilage, and damage. However, the use of synthetic plastics in food packaging has been linked to a number of environmental and health concerns. In recent years, there has been growing interest in the development of sustainable food packaging materials that are biodegradable, compostable, and non-toxic. Anchote starch is a renewable resource that is produced from the roots of the anchote plant. Anchote starch has excellent film-forming properties and can be used to produce biodegradable food packaging films. Cellulose nanocrystals (CNCs) are a promising material for use in sustainable food packaging. CNCs are a natural, biodegradable, and non-toxic material that has excellent mechanical, optical, and antimicrobial properties. Rosemary essential oil is a natural antimicrobial agent that has been shown to inhibit the growth of a variety of bacteria and fungi. The addition of rosemary essential oil to food packaging films can help to improve the antimicrobial properties of the film and protect food from spoilage. The purpose of this study was to develop and characterize CNC reinforced anchote starch-based antimicrobial food packaging film containing rosemary essential oil. Anchote CNC (AnchCNC) was extracted from anchote bagasse (AnchB) by acid hydrolysis method. Anchote starch based antimicrobial nanocomposite (AS/AnchCNC/REO) films incorporated with anchote cellulose nanocrystals (AnchCNC) (1, 3 and 5%) and rosemary essential oil (REO) (2, 4, and 6%) were prepared by the solvent casting method. The chemical components of AnchB and AnchCNC were determined. AnchB, Anchote cellulose (AnchC), and AnchCNC were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), and size distribution analysis. The thickness, moisture content, water solubility, water vapor permeability (WVP), mechanical properties and antimicrobial properties of Anchote starch (AS) and AS/AnchCNC/REO films were analyzed. Films containing (3% AnchCNC; 2% REO) and (5% AnchCNC; 2% REO) were chosen based on better tensile strength and their FTIR, thermal, and morphological characteristics were examined. The polyphenol content and antioxidant activity (DPPH inhibition) of films were also determined. The migration of polyphenol from the films to water and ethanol food simulant was studied at 30 °C after 7 days. The release rate and diffusion coefficient of polyphenol migration from the film sample F33 (5% AnchCNC, 6% REO) into water food simulant were determined by overall kinetics and diffusion modeling at 30, 40, 50 and 60 °C. The stability of polyphenol at an ambient storage temperature of 25 °C, as well as the antimicrobial application of the films for meat preservation was evaluated. The chemical treatments (alkali treatment, bleaching, and acid hydrolysis) effectively removed hemicelluloses and lignin from AnchB. The thermal stability of AnchCNC was reduced after acid hydrolysis due to the introduction of sulfate groups. XRD measurements revealed an increase in the crystallinity by 160 % after the chemical treatments. SEM images clearly exhibited an effective removal of the amorphous fractions after the chemical treatments. Zeta sizer analysis showed that AnchCNC had an apparent average diameter of 92 nm and zeta potential value of -21.0 mV. The tensile strength (TS) and WVP of anchote starch films were both dramatically improved by increasing the amount of AnchCNC. A significant reduction in the WVP of films was seen when the amount of REO was increased. The TS property of the films was found to decrease as the concentration of REO was increased. The TS of the AS (control) film was 9.42 MPa. Films containing (3% AnchCNC; 2% REO) and (5% AnchCNC; 2% REO) had shown the highest TS values of 23.41 MPa and 23.44 MPa, respectively. With the addition of 5% AnchCNC and 6% REO, the WVP of anchote starch film was decreased from 8.72 × 10-11 gH2O/Pa.m.s to 3.11 × 10-11 gH2O/Pa.m.s. The antimicrobial films showed satisfactory antimicrobial efficiency against E. coli, Staphylococcus aureus, and Listeria monocytogenes. REO significantly contributed to the antimicrobial efficiency of films. A sample containing the highest percentage (5% AnchCNC and 6% REO) recorded the highest antibacterial efficiency. TGA results showed films containing, 3 % AnchCNC; 2% REO (F21) and 5 % AnchCNC; 2 % REO (F31) had better thermal properties than the control (AS) film. The polyphenol content of films was in the range of 1.8 to 6.11 mg GAE/g dried films. The percentages of DPPH inhibition were between 15 to 53%. The film with highest AnchCNC and REO (5% AnchCNC, 6% REO) had the highest levels of polyphenols and DPPH inhibition. The results showed that the polyphenol content and antioxidant activity of films were increased proportionally with increasing AnchCNC and REO content. The total polyphenol concentrations that migrated to aqueous medium at 30 °C after 7 days were in the range of 17 to 60 mg GAE/kg food simulant for water food simulant. As expected, film sample F33 with (5% AnchCNC, 6% REO) had the highest concentration for the migration of polyphenols. The initial release rate of polyphenol, νo for film, F33 at four different temperatures, determined from the overall firstorder kinetics model were in the range of 8.3 × 10-7 to 36 × 10-7 g/s. The release of polyphenol into water food simulant at different temperatures were consistent to short-term and long-term diffusion models with diffusion coefficient values between 5.0 × 10-12 and 9.1 × 10-16 m2/s. The films produced displayed good antibacterial activity against the growth of E. coli, L. monocytogenes and S. aureus on meat products. The film with AnchCNC (5%) and REO content of (6%) were found to extend the shelf-life of meat beyond 50%, suggesting that the film may have great potential in active packaging for extending the shelf-life of foodstuffs. The findings implied that the film would have significant potential for active packaging to increase the shelf life of food products with good mechanical and barrier capabilities.Item Development and Quality Assessment of value-added Fish Products(Addis Ababa University, 2021-12) Meron Teklu; Shimelis, Admassu (Prof.)The goal of the present study was to develop and assess the quality of Value added fish products derived from Oreochromis niloticus tana (Nile tilapia). Fish ball and fish nuggets Products were prepared, recorded, and analyzed using different parameters like proximate analysis, microbiological analysis, physicochemical analysis, texture analysis, and sensory analysis. The moisture, protein, fat, ash and carbohydrate contents of fish balls The study revealed that samples varied between 50.03% - 80.35%, 13.30% - 18.08 %, 11.83% 14.83 %, 1.90% - 2.07% , 10.97 % - 15.02% respectively.Fish Nuggets (FFA) product had a better acceptability during storage at 4°C for 6 days in microbiological parameters like TPC, E. coli and S. aureus as well as Chemical analysis showed that fish ball and fish nuggets contained high protein, fat, due to frying process. Moreover, the textural properties which include hardness, cohesiveness, springiness and chewiness of the products exhibited more firmness after cooking (p<.05). Moreover, the sensory evaluation showed that acceptability of fish nuggets was more than that for fish ball. These results showed that fish nuggets had higher quality indicators rather than fish ball.Item Development and Quality Evaluation of Biscuit and Cookies Made from Wheat Flour Supplemented with Kocho Powder(Addis Ababa University, 2021-12) Dinkitu, Jaleta; Shimelis, Admassu (Prof.)Biscuit and cookies are ready-to-eat inexpensive food products that are consumed among all age groups. This thesis work was performed to develop and quality evaluation of biscuits and cookies made from wheat flour supplemented with kocho powder. The wheat flour and kocho powder were used to develop biscuits (80:20, 70:30, 60:40, and 50:50% of substitution ) and 100% wheat flour as a control.The data generated were statistically analyzed by ANOVA using SPSS. Proximate analysis were carried out on the flour,biscuits and cookies samples.And also water and oil absorption capacities were carried out on the flour and texture and color analysis were carrried out on the biscuits samples.The results of proximate composition, energy content and water activity shows that the wheat flour(control flour) contained 14.8% of moisture content, 0.45% 0f ash content, 10.237% of protein value, 1.5% of fat value, 0.5% of fiber, 72.52% of carbohydrate value, 344.5kcal/100g and 0.528% of water activity. The results indicated that the control flour showed higher level of moisture content, protein content, fat content, energy value and lower level of ash content, carbohydrate content, fiber content, water activity content while composite flours showed higher level of ash content, carbohydrate content, fiber content water activity content and lower level of moisture content, , protein content, fat content and energy value. Improvements were also noted in mineral contents such as magnesium, iron and calcium in biscuit produced from the composite flour of wheat supplemented with different levels of kocho powder. Physical (weight, thickness) and sensory (taste, colour, texture, appearance, flavor, overall acceptability) attributes of biscuits made from kocho powder and wheat flour were analyzed. The sensory acceptability was evaluated by a seven point’s hedonic scale. As the kocho powder addition decreased from 50 % to 20 %, the thickness, and the sensory attributes (taste, flavor, appreance,color,texture preference and overall acceptability) of the biscuits got increased. From the result, texture, taste, Colour, flavor,appearance and overall acceptability did not show any significant difference(P≥0.05) among different samples. As a result, the high nutritive and flavor rich biscuits and cookies generated in this study are to provide health benefits.Item Evaluation of Bashekala Barley-Wheat Flour and Starch Properties for Biscuit Production(Addis Ababa University, 2022-02) Teketel, Geto; Shimelis, Admassu (Prof.)This study examined the properties of the bashekala barley-wheat flour and starch for biscuit production. The effects of the bashekala barley-wheat flour blends on proximate analysis, functional properties, pasting, farinograph analysis, and sensory analysis were evaluated using standard laboratory procedures, and statistics were conducted using ANOVA and SPSS. The bashekala barley-wheat blend was developed using the D-optimal mixture design software. The proximate analysis of the blend bashekala barley-wheat blend ratio (20:80) revealed a significant effect (p<0.05) on the crude protein, moisture, ash, fat, carbohydrate, and crude fiber content. As per sensory evaluation of biscuits results (20:80%) and (60:40%) blend rations made biscuits with superior sensory properties, and excellent acceptability. Further, as bashekala barley flour substitution levels increased, the texture profiles of biscuit products increased with biscuit hardness, the crust color of the biscuits changed from dull to darker brown, but biscuit fracture ability decreased as bashekala barley flour substitution levels increased. The farinographic properties of blended ratio flour (20:80%) (25:75%), (40:60%), and (100/0%) was significant with (p<0.05) between WA, DS, DDT, and FQN respectively. In conclusion, bashekala barley flour water absorption properties are superior, the 20% bashekala barley flour blend ratio had superior sensory characteristics, and its flour substitution could significantly contribute to the development of biscuits.Item Development of Weaning Food from a Blend of Oat, Rice and Cowpea Flour(Addis Ababa University, 2021-12) Sewbesew, Tefera; Adamu, Zegeye (Assoc. Prof.)Cereals and legumes are highly cultivated plants in Ethiopia.They contain high macro and micronutrients, but they have anti-nutritional factors by nature which limit the bioavailability of food nutrients.This study focused on development of weaning food from Oat, Rice, and Cowpea flour for the age group of 6 to 24 months babies. This age is a critical period of mental, physical, and intellectual development.Raw materials were selected based on nutritional availability. Roasting method was used at 100,120, and 140 oc, Blending ratio refers 60 to 70% cereals and 30 to 40% legumes.Ratio1(50% Oat,10% Rice,40%Cowpea) contained higher protein content than Ratio2 and Ratio3 this is because of the avalibilty of high amount of Cowpea. Optimization using Minitab 17 software was used in order to formulate the nutrient and to compare the product from commercial product which is FAFFA flour.The roasting process and blending ratio had a significant (P<0.05) effect on proximate composition, functional properties, anti-nutritional factor, mineral content, and microbial analysis.According to optimized result P2,P3&P9 labled weaning products have been found good nutrietious especially P3(ratio1with140oc roasting temperature) was selected of having optimum protein and energy containing 18.1%protein, 4.9%fat, 70.8%carbohydrate and 400.2kcal energy.As roasting temperature incresed the same ratio of protein,fat, ash and mineral contents were significantly (P<0.05) increased but moisture and fiber contents were decreased. WaterAbsorption Capacity(WAC) and Oil Absorption Capacity(OAC) of the formulated products ranged between 2.01 to 2.85 and 1.57 to 1.94ml/g,respectively,which were higher than the raw material values.Bulk density of the formulated products were lower than the raw material values due to roasting.After processing both phytate and tannin content of formulated products were decreased due to roasting so increased bioavalablity of products.Item Development of gluten-free biscuit from a blend of Teff, Sorghum and Cowpea Flour(Addis Ababa University, 2021-12) Rebka, Temam; Adamu, Zegeye (Assoc. Prof.)The study was conducted to develop gluten-free and protein-rich biscuit to achieve nutritionally improved quality product and reduce celiac problem which arises with gluten content. Teff (Boset variety), Sorghum (Melkam variety) and Cowpea (Bole variety) were collected from Debrezeit and Awash Melkasa Agricultural Research Centers. The raw materials were cleaned, soaked(cowpea), dehulled(cowpea), dried(cowpea), milled and sieved before blended flour preparation. Blend proportions of Teff, Sorghum and Cowpea were prepared as S1 (65%: 20%: 15%), S2 (40%: 25%:35%) and S3 (50%:30%:20%) ratios, respectively using D-optimal design software. In this study, proximate composition, functional properties, anti-nutritional properties, mineral content and sensory analysis were conducted. Biscuit samples were prepared with temperature controlled oven at 205ᵒc for 10 minutes. The results showed that the protein and fat contents of biscuit product were directly proportional to the amount of cowpea flour added in the blend proportion, biscuit having 35% cowpea or S2 being the highest ( 15.4g/100g and 8.5g/100g). Mineral content increment for Fe, Zn and Ca was 9.33 to 12.05, 2.62 to2.95 and 95.34 to 116.3mg/100g respectively with increasing teff proportion. Tannin (23.08mg/100g) and phytates (439.23mg/100g) were higher in higher cowpea and teff addition respectively. Functional properties such as water absorption capacity(2.15ml/gm), oil absorption capacity(1.73ml/g) and bulk density (0.94g/ml) registered the highest values.. pH values of samples were 6.39, 6.49 and 6.45 respectively for S1 (65%: 20%: 15%), S2(40%: 25%:35%) and S3(50%:30%:20%) in the blend proportions respectively. The highest overall sensory acceptability score was 7.8(S3) which was liked moderately next to the control biscuit sample. S3 also scored highest in texture (7.65), appearance (7.8) and taste (7.65) parameters whereas the color (7.7) of S1 biscuit sample was better liked by panelists.