Standardization of teff (Eragrostis teff) injera making process conditions for better physicochemical and sensory quality.

Injera is a type of flatbread that is fermented, naturally leavened, and native to Ethiopia. However, injera quality can vary depending on the processing steps used, even if the same variety of teff is used. This research was conducted to optimize the prebaking processing and baking conditions to produce better quality teff injera suitable for industrial and export purposes. Four experiments were conducted to optimize the injera-making process. The first two phases focused on optimizing the prebaking processing conditions (fermentation temperature and time, absit mixing ratio, absit cooking time, and secondary fermentation time). The best physicochemical qualities were obtained at a primary fermentation temperature of 25°C for 64 h, an 8% mixing ratio of absit with 10 min of cooking, and a secondary fermentation time of 4 h. In the third phase, baking temperature (195 ± 5, 215 ± 5, 235 ± 5, and 255 ± 5°C) and time (1, 2, and 3 min) were evaluated. The results showed that the best response variables were obtained at a temperature of 255 ± 5°C for 2 min or 235 ± 5°C for 3 min. Finally, the optimized conditions were validated on five different varieties [DZ-Cr-387, DZ-Cr-2124, white (T-BT), white (T-GK), and sergegna teff (T-E)] of teff grain. The results indicated that the optimized conditions could produce better quality and consistent teff injera on a large commercial scale, which would suit both local and export markets.

Physicochemical stability and sensory quality of selected Ethiopian coffee (Coffea arabica L.) brands as affected by packaging materials during storage.

Ethiopia's economy heavily relies on coffee, the country's primary export. However, there is a need for improvement in the current packaging materials for parchment coffee during extended storage. An experiment was conducted to evaluate the effectiveness of four different packaging materials (Jute, Woven Polypropylene internally lined with low-density propylene, Grain Pro, and Purdue Improved Crop Storage) on the quality of three brands of Parchment Coffee (Limu, Sidama, and Yirgacheffe) stored for 12 months. The results demonstrated that hermetic packaging materials like Purdue Improved Crop Storage and Grain Pro bags outperformed the Jute bag control in maintaining the original coffee quality throughout the storage period. There was a significant interaction between the coffee brands and the packaging materials for most measured parameters, except bioactive compounds. Notably, Sidama and Yirgacheffe brands stored in hermetic bags consistently achieved cup quality values above 80 %, meeting the requirements for specialty coffee grade. However, the Limu brand did not meet the specialty coffee criteria. The study recommends using hermetic storage materials such as PICS and Grain Pro bags for extended coffee storage. By adopting these methods, the renowned Ethiopian coffee brands can uphold their exceptional quality standards in the international market and ensure customer satisfaction.

Bioactive compounds in coffee and their role in lowering the risk of major public health consequences: A review.

This article addresses the bioactive components in coffee aroma, their metabolism, and the mechanism of action in lowering the risk of various potential health problems. The main bioactive components involved in the perceived aroma of coffee and its related health benefits are caffeine, chlorogenic acid (CGA), trigonelline, diterpenes, and melanoids. These compounds are involved in various physiological activities. Caffeine has been shown to have anticancer properties, as well as the ability to prevent the onset and progression of hepatocellular carcinoma and to be anti-inflammatory. CGA exhibits antioxidant action and is implicated in gut health, neurodegenerative disease protection, type 2 diabetes, and cardiovascular disease prevention. Furthermore, together with diterpenes, CGA has been linked to anticancer activity. Trigonelline, on the other side, has been found to lower oxidative stress by increasing antioxidant enzyme activity and scavenging reactive oxygen species. It also prevents the formation of kidney stones. Diterpenes and melanoids possess anti-inflammatory and antioxidant properties, respectively. Consuming three to four cups of filtered coffee per day, depending on an individual's physiological condition and health status, has been linked to a lower risk of several degenerative diseases. Despite their health benefits, excessive coffee intake above the recommended daily dosage, calcium and vitamin D deficiency, and unfiltered coffee consumption all increase the risk of potential health concerns. In conclusion, moderate coffee consumption lowers the risk of different noncommunicable diseases.

Assessment of Physicochemical and Microbiological Characteristics of Honey in Southwest Ethiopia: Detection of Adulteration through Analytical Simulation.

This study aimed to evaluate the quality of honey in the supply chain from the Gera district to Jimma town in southwest Ethiopia and develop a predictive model to detect adulteration. A preliminary survey revealed that poor handling practices and adulteration negatively impacted honey's physicochemical and microbial quality. For laboratory analysis, 268 honey samples were collected from households, cooperatives, chira markets, Agaro markets, and Jimma markets. They were mixed separately to create composite samples representing different value chain actors. Laboratory results indicated that honey samples from supply chain actors confirmed significant differences (p < 0.05) in physicochemical and microbial quality. The study found that the extent of adulteration and physicochemical quality loss increased from producers to Jimma retailers, indicating multiple-stage adulteration along the supply chain that could pose a risk to the safety and quality of the product. The physicochemical quality parameters of the honey samples in the study varied within the following ranges: moisture (18.35-19.42%), water activity (0.48-0.61), viscosity (7.45-10.28 Pas), pH (3.41-4.0), titratable acidity (34.01-36.03 meq/kg), ash (0.1-0.23%), electrical conductivity (0.25-0.39 mS/cm), Total Soluble Solid (75.9-77.5 °Brix), Water insoluble Solid (0.16-2.48 g/100 g), Diastase Activity (6-14 DN), and Hydroxymethylfurfural (0.2-27.7 mg/kg). Microbiological analyses showed that total aerobic bacterial and fungal load ranged from 2.7 × 101-2.29 × 102 and 3.2 × 101-4.57 × 102, respectively. A predictive model was developed using adulteration indicator parameters, showing good linearity (R2>90%) and predictive capacity for detecting adulteration with sugar syrup.

Harmonizing Drying Time, Layer Thickness, and Drier Zones for Drying Kinetics: Quality and Safety of Solar Tunnel-Dried Wet-Processed Parchment Coffee (Coffea arabica L.).

Tunnel solar dryer is the recently used drying method for better quality and safety of parchment coffee. However, the higher variation of drying temperature and RH along the long tunnel solar dryer results in a heterogeneous environment in the tunnel, which could make parchment coffee dried at different times or with different moisture contents. This study is aimed at investigating the effect of solar tunnel dryer zones at different zones of the dryer, divided into three zones from the inlet to the exit side of the drier and drying layer thicknesses on the drying time, drying kinetics, physicochemical, sensory, and fungal growth loads of parchment coffee. Furthermore, seven mathematical models were evaluated to select the best-fitting model for a specific zone to predict drying time. Results showed that dryer zones significantly (p < 0.05) interacted with layer thickness for most of the measured parameters except titratable acidity and sensory properties. The dryer zone, coupled with the reduction in drying layer thickness, caused an increase in effective diffusivity and moisture removal rate and reduced drying time. The drying time to reach constant moisture content varied from 14 to 17 hours. Overall raw bean, cup, and total quality varied from 36.3 to 37, 48 to 51, and 84.3 to 87.3%, respectively. Values for physicochemical parameters ranged from 5.3 to 6.9 (pH), 2.1 to 2.6% (titratable acidity), 2.3 to 4.3°Brix TSS, 10.9 to 15.2% (ether extract), 39.2 to 53.5GAE/g (total phenolic content), and 38.5 to 59.2 (DPPH scavenging capacity). The fungal infection percentage at the end of drying varied from 4 to 93.3%, which could be associated with potential mycotoxin formation if recommended conditions were not maintained. In general, for better quality, similar drying times, and a lesser fungal load, it is recommended to use 4, 5, and 6 cm layer thickness in zones one, two, and three, respectively. The drying kinetics of parchment coffee in different dryer zones with different drying layer thicknesses showed variation. Zone one at 2 and 4 cm layer thicknesses is best described by the Verma model. Four- and six-centimetre layer thicknesses in zones 2 and 3 are best described by the modified Midilli model.

Metabolomics: A suitable foodomics approach to the geographical origin traceability of Ethiopian Arabica specialty coffees.

Coffee arabica, originated in Ethiopia, is considered a quality bean for its high sensory qualities, and has a special price in the world coffee market. The country is a pool of genetic diversity for Arabica coffee, and coffee from different regions has a distinct flavor profile. Their exceptional quality is attributed to their genetic diversity, favorable environmental conditions, and agroforestry-based production system. However, the country still needs to benefit from its single-origin product due to a lack of appropriate traceability information to register for its geographical indication. Certification of certain plants or plant-derived products emerged to inform consumers about their exceptional qualities due to their geographical origin and protect the product from fraud. The recently emerging foodomics approaches, namely proteomics, genomics, and metabolomics, are reported as suitable means of regional agri-food product authentication and traceability. Particularly, the metabolomics approach provides truthful information on product traceability. Despite efforts by some researchers to trace the geographical origin of Ethiopian Arabica coffees through stable isotope and phenolic compound profiling and elemental analysis, foodomics approaches are not used to trace the geographical origin of Arabica specialty coffees from various parts of the country. A metabolomics-based traceability system that demonstrates the connection between the exceptional attributes of Ethiopian Arabica specialty coffees and their geographic origin is recommended to maximize the benefit of single-origin coffees.

Nutritional and Phytochemical Composition and Associated Health Benefits of Oat (Avena sativa) Grains and Oat-Based Fermented Food Products.

Oats (Avena sativa L.) are a popular functional cereal grain due to their numerous health benefits. This review article summarized the information on the chemical composition and phytonutrients of oats grown in different countries. It also reviewed recently developed fermented oat products to highlight their potential for human health. Oats have an interesting nutritional profile that includes high-quality protein, unsaturated fats, soluble fiber, polyphenolic compounds, and micronutrients. Oat grain has a unique protein composition, with globulins serving as the primary storage protein, in contrast to other cereals, where prolamins are the main storage proteins. Oats have the highest fat content of any cereal, with low saturated fatty acids and high essential unsaturated fatty acid content, which can help reduce the risk of cardiovascular diseases. Oats are a good source of soluble dietary fiber, particularly ß-glucan, which has outstanding functional properties and is extremely important in human nutrition. ß-Glucan has been shown to lower blood cholesterol and glucose absorption in the intestine, thereby preventing diseases such as cardiovascular injury, dyslipidemia, hypertension, inflammatory state, and type 2 diabetes. Oats also contain high concentration of antioxidant compounds. Avenanthramides, which are unique to oats, are powerful antioxidants with high antioxidative activity in humans. Recognizing the nutritional benefits of oats, oat-based fermented food products are gaining popularity as functional foods with high probiotic potential.

Effect of pretreatments and solar tunnel dryer zones on functional properties, proximate composition, and bioactive components of pumpkin (Cucurbita maxima) pulp powder.

Pumpkin fruits are large in size and need to be cut into pieces for use. The quality and storage life of cuts rapidly deteriorated. Big size fruits can be converted to shelf stable product to minimize postharvest loss using solar driers. However, drying temperature and RH in long solar tunnel drier not uniform and may affects quality of dried products. Therefore this research work aimed to investigate the effects of pre-drying treatments and solar tunnel dryer zones on the functional properties, proximate composition, and bioactive components of pumpkin pulp powder. Three groups of pumpkin slices were pre-treated in 1% citric acid (20 min), 2% salt (20 min) solutions, and the other group blanched at 65 °C in 1% salt solution (2 min), untreated sample used as a control. Pre-treated samples then dried in three zones of tunnel solar drier (zone I, zone II and zone III). Treatment combinations were laid down in factorial RCBD replicated 3 times. Results showed that pulp powder from salt pre-treated slice and dried at zone III results in the highest values of shrinkage, rehydration ratio, water holding capacity, and bulk density. Moisture content decreased from zone I to III, and with salt blanching in range of 8.2 to 6.4%, no effect in crude fat content, slices pre-treated in 2% salt solution results is better crude protein and fiber contents in zones. Better retention of total polyphones, beta-carotene, ascorbic acid, with high DPPH scavenging activity and lowest IC50 values were observed for salt pre-treated sample but dried in zone II of the drier. In general relatively better functional properties, proximate composition and bioactive compounds of the powder can be preserved when slices pre-treated in 2% salt solution and dried in zone II of solar tunnel drier characterized by 54.9 ± 3.7 °C, RH value of 31.4 ± 3.4% and air velocity of 0.45 m/s.

Optimization of nutritional and sensory properties of fermented oat-based composite beverage.

Oat (Avena sativa) is well-known for its nutritional value and health-promoting properties. There are only a few oat-based value-added products on the market in Ethiopia, and this study attempted to develop a new product that is both nutritionally enhanced and sensory acceptable, therefore, the objective of this study was to optimize the nutritional and sensory properties of a beverage made from oat, lupine (Lupinus albus), stinging nettle (Urtica simensis), and premix. D-optimal mixture experimental design was used to generate 11 runs applying the following constraints: 60-70% toasted oat, 10-25% roasted and soaked de-bittered white lupine, 5-15% boiled stinging nettle leaves, and 10% premix (flour of toasted black cardamom (2.8%), malted wheat (2.8%), pumpkin (2.6%), spiced chili peppers (1.1%), and table salt (0.7%). Statistical model evaluation and optimization were carried out using Minitab 19 software. The nutritional composition of the product was assessed, and results show that increasing the proportion of oat flour in the blend resulted in a significant (p < 0.05) increase in fat, carbohydrate, gross energy, and mineral contents (Fe, Zn). An increase in lupine flour increased crude protein, crude fiber, gross energy, phytate, tannin, oxalate, and antinutrient to mineral molar ratios. In contrast increased in stinging nettle leaf powder increased the ash and beta-carotene contents. Sensory of 11 composite sample beverages and control (90% oat plus 10% premix) were also carried out by 50 untrained panelists. Consequently, eight responses were optimized: protein, fat, Fe, Zn, beta-carotene, taste, appearance, and overall acceptability. The optimal blending ratio obtained was 70% oats, 11.3% lupine, 8.7% stinging nettle flour, and 10.0% premix. The study's findings suggested that the optimal combination of these traditionally processed ingredients in a beverage can be considered a valuable food with the potential to improve diet quality.

Effect of Oromo Dinich (Plectranthus edulis) flour supplemented on quality characteristics of teff-maize composite injera.

Blending Oromo dinich flours with cereals-based flours significantly enhances the nutritional potential of cereals-based products. Therefore, this study aimed to develop and evaluate the quality of teff-based injera supplemented by underutilized indigenous tuber Oromo dinich (Plectranthus edulis) and maize flours. Fourteen formulations were generated using D-optimal constrained mixture design with a range of maize (5-15%), Plectranthus edulis (5-15%), and teff (70-90%). Statistical evaluation and optimization were done using D-optimal mixture design expert software. The results showed that the supplementation of more Plectranthus edulis flour in the formulations indicated better improvements in terms of protein (10-10.8%), fat (2.4-2.8%), gross energy contents (380.7-391.9 kcal/100g), total phenolic content (8.6-15.8 mg GAE/g) and total antioxidant capacity (66.20-82.7%) at the concentration of 3.32 mg/mL. The sensory acceptability of the injera was significantly (p < 0.05) liked in terms of aroma with increasing the ratio of Plectranthus edulis and maize flours. The optimum value of the blending ratio was 77.6% teff, 13.1% maize, and 9.3% Plectranthus edulis flours with desirable nutritional composition of injera, which varied for protein (10.7-10.8%), fat (2.62-2.8%) and energy (388.3-391.9 kcal/100g) and overall acceptance (5.5-6.3) with the desirability of 0.66. The optimization results indicated that supplementing Plectranthus edulis flour up to 10% with teff-maize composite flours were acceptable in terms of nutritional composition and sensory quality. Thus, supplementing underutilized indigenous Plectranthus edulis tuber flour with teff-maize flours significantly enhanced the nutritional potential of injera products.

Effect of Pretreatments and Solar Tunnel Dryer Zone on Drying Characteristics and Stability of Pumpkin (Cucurbita maxima) Slices.

Drying fruits and vegetables can be achieved using different drying methods based on the crop's economic value and the technology's affordability. However, in Sub-Saharan Africa, where sunlight intensity and duration are high, it is recommended to use solar drying methods. A solar tunnel dryer is one of the methods commonly used to produce dried fruits and vegetables. It is necessary to determine the drying kinetics at different dryer zones and select a suitable drying kinetics model to overcome the limitation. In addition, pretreatment methods are commonly recommended to improve the quality of the dried product. This work aimed to determine the drying kinetics of pumpkin slices at different zones of drier and pretreatment effect on product quality. Three zones of drier and four pretreatments were employed in the two-factor factorial experiment. Seven thin layer kinetic models were evaluated. pH, TSS, TA, moisture content (MC), and water activity (a w) were determined for quality evaluation. Recorded data showed that the temperature in the tunnel increased from zone I to III with a decrease in RH. Results showed a higher drying constant (K) and effective diffusivity (D eff); drier zone III > II > I. Pretreatments also showed a significant effect on K and D eff. Regardless of pretreatment types, two-term exponential and diffusion models are better fitted for zones I and II/III, respectively. With pretreatments and drier zones, the TSS value increases from zones I to III but with a decrease in titratable acidity, moisture content, and water activity. From the result, it can be concluded that different drying rates are observed in different zones. However, a better quality of pumpkin powder was observed in drier zone II for pumpkin slices pretreated with a 2% salt solution. It is recommended to create a drying medium that resembles zone II or better to use the recommended kinetic models to predict the drying time for each zone for a better quality product by avoiding under- or over-drying of slices.

Anchote (Coccinia abyssinica [Lam.] Cogn.) powder, an underutilized indigenous crop, as a substitute to commercial pectin in the production of strawberry jam.

The study investigated the potential of anchote (Coccinia abyssinica [Lam.] Cogn.) tuber powder as a substitute to commercial pectin. Mixture D-optimal design was used to generate 14 experimental runs using ranges: strawberry fruit (45-55%), sugar (43-53%), and anchote powder (0.75-1.75%). The effect of anchote powder on physicochemical and textural qualities of the jams was evaluated. The parameters measured include: moisture content (30.7-32.8%), total soluble solid (50.7-65.4 ºBrix), water activity (0.73-0.80), pH (2.93-3.13), titratable acidity (0.58-0.72%), gel strength (326.39-440.37 g mm), hardness (26.36-35.09 g), cohesiveness (0.89-0.94), energy of penetration (418.72-489.51 g s), adhesiveness (-25.38 to -103.79 g s) and stickiness (-13.78 to -29.22 g). The jam formulation J13 (50% strawberry, 48.2% sugar, 1.33% anchote) was best performing. Numerical optimization showed the best combination of parameters at 52.4% strawberry, 46.0% sugar, 1.07% anchote. The jam formulated with anchote powder was comparable with the jam made using pectin.

Nutritional compositions and bioactive compounds of "Shameta", A traditional home made fermented porridge provided exclusively to lactating mothers in the western part of Ethiopia.

In developing countries, fermentation is one of the traditional food processing methods for production of relatively safe and nutritious foods. Among many fermented foods in Ethiopia, "Shameta" is one of the locally produced and consumed cereal-based fermented porridge mainly used to support strength and recovery of lactating women after birth. However, even though the product is consumed for years, so far, the nutritional composition and bioactive compounds of the porridge not yet scientifically determined. This study aimed to determine the physicochemical properties, nutritional composition and bioactive compounds of "Shameta" commonly produced and consumed in Western part of the country. A total of 27 "Shameta" samples were collected from houses of lactating mothers residing in different districts of East Wollega zone. Results showed that, "Shameta" sample prepared from blend of maize and barely supplemented with faba bean results in crude protein content of 11.2 g/100g as compared with samples without faba bean, 6.8 g/100g. Samples supplemented with more proportion of rapeseed as oil source resulted in relatively higher crude fat content (12.2 g/100 g) as compared to other samples. From energy point of view, "Shameta" could provide about 85% of the extra energy needs of lactating mothers as compared to staple foods consumed in sample collection areas. It is also confirmed that, the product is a good source of iron and zinc, with the highest scores of 8.1 and 8.6 mg/100g in some samples, respectively, as compared to other mineral elements whose scores were much less than the daily recommended allowances. The average phytate and tannin contents were 0.79 and 0.18 mg/100g, respectively. Even though the Ca, Fe and Zn contents were below the recommended daily allowance, their bioavailability could not be hindered by phytate and tannin. Results also showed that samples have good antioxidant potential to minimize oxidative stresses. It could be deduced that as a sole food for the mothers, the product could not provide sufficient protein and some minerals to meet recommended daily allowance. However, to enhance the importance of the product, it is necessary to optimize the ingredient compositions and processing conditions to meet the nutrient demand of lactating mothers.

Starch composition and functional properties of raw and pretreated anchote (Coccinia abyssinica (Lam.) Cogn.) tuber flours dried at different temperatures.

Anchote (Coccinia abyssinica (Lam.) Cogn.) is an indigenous tuber crop produced in southwest part of Ethiopia. As an indigenous and underutilized tuber, limited scientific information is available about the characteristics of dried anchote powder. In this study, attempts were made to investigate the starch composition and functional properties of flours produced from the raw and pretreated tuber dried at different temperatures (60, 80, and 100°C). The results showed that both pretreatment and drying temperature significantly (p < .05) affected the amylose/amylopectin ratio, pH, total soluble solids (TSS), water absorption capacity (WAC), oil absorption capacity (OAC), water absorption index (WAI), water solubility index (WSI), swelling power (SP), total polyphenols content (TPC), and total flavonoid content (TFC). The treatment combinations result in varied ranges of pH (5.70-6.47), TSS (5.37-10.8 °Brix), WAC (2.42-4.21 g/g), OAC (0.94-1.44 g/g), WAI (3.40-5.42 g/g), WSI (11.40%-20.37%), SP (4.56-7.20 g/g), foaming capacity (FC) (3.31%-33.33%), foam stability (FS) (1.89%-20.00%), amylose content (AC) (14.18%-36.11% ), TPC (0.22-0.80 mg GAE/g), and TFC content (0.12-0.44 mg CE/g). The blanched and boiled anchote flours dried at relatively lower drying temperature exhibited better WAC, SP, and WAI than the raw. Considering the determined parameters, the flour from the tuber can be used as an ingredient in different food formulations.

Application of nanotechnology in agriculture, postharvest loss reduction and food processing: food security implication and challenges.

Ensuring food security in developing countries is highly challenging due to low productivity of the agriculture sector, degradation of natural resources, high post farming losses, less or no value addition, and high population growth. Researchers are striving to adopt newer technologies to enhance supply to narrow the food demand gap. Nanotechnology is one of the promising technologies that could improve agricultural productivity via nano fertilizers, use of efficient herbicides and pesticides, soil feature regulation, wastewater management, and pathogen detection. It is equally beneficial for industrial food processing with enhanced food production with excellent market value, elevated nutritional and sensing property, improved safety, and better antimicrobial protection. Nanotechnology can also reduce post-farming losses by increasing the shelf life with the aid of nanoparticles. However, further investigation is required to solve the safety and health risks associated with the technology.

Optimization of nutritional and sensory qualities of complementary foods prepared from sorghum, soybean, karkade and premix in Benishangul - Gumuz region, Ethiopia.

Consumption of nutritionally deficient complementary foods in developing countries is among the main contributing factors to infants and young children's malnutrition. Therefore, this study was aimed to optimize the nutritional and sensory properties of complementary food made from malted sorghum, blanched soybean, boiled karkade seeds and premix. A D-optimal mixture experimental design with 18 runs was generated by design expert software within in the constrained: 40-60% malted sorghum, 20-30% blanched soybean, 10-20% boiled karkade seeds and 10% premix (5.0% figl leaf powder, 4.5% sugar and 0.5% iodized table salt). Statistical model evaluation and optimization were done using D-optimal mixture design expert software. Sensory evaluation was conducted using 53 untrained panelists on two selected formulations and the control (local formulation). The study shows that with an increasing ratio of blanched soybean and boiled karkade seeds flour in the blend, a significant (p < 0.05) increase in protein, fat, energy and mineral contents, and a decrease in tannin and phytic acid contents of high mineral bioavailability except for oxalate: calcium ratio in the formulations were observed. The optimal blending ratio was 45.0% malted sorghum, 26.0% blanched soybean, and 19.0% boiled karkade seeds flour plus 10.0% premix. The gruel made from the new formula was significantly (p < 0.05) liked in terms of aroma, flavor, mouthfeel and overall acceptability than the control sample. The findings suggested that the optimal mix of these traditionally processed ingredients can potentially alleviate protein-energy malnutrition and micronutrient deficiency to mitigate expensive commercial infant complementary foods sold in the market.

Proximate, mineral and anti-nutrient compositions of oat grains (Avena sativa) cultivated in Ethiopia: implications for nutrition and mineral bioavailability.

Oat (Avena sativa) is an underutilized cereal grain in Ethiopia from the Poaceae grass family. This study aimed to investigate the proximate, mineral, and anti-nutrient composition of three landrace varieties commonly used in certain districts of the country and compare them with two improved varieties of oats in Ethiopia. The proximate and mineral composition was determined using the Association of Official Analytical Chemists (AOAC) standard methods. Phytate and tannin contents were determined using the spectroscopic method, and oxalate was analyzed using HPLC. The bioavailability of minerals was also estimated. Results showed significant (p < 0.05) differences in proximate, mineral, and anti-nutrient compositions among studied varieties. The moisture, crude protein, crude fat, crude fiber, ash, and total carbohydrate contents were in the range between 8.5-9.8, 11.9-15.8, 6.7-10.3, 2.1-3.5, 1.2-1.3, and 72.6-74.3 g/100 g DM, respectively. Iron, copper, zinc, magnesium, calcium, and potassium contents were 2.5-3.0, 0.2-0.4, 1.6-2.0, 62.4-89.1, 44.0-102.7, and 241.7-258.3 mg/100 g DM, respectively. The oxalate, tannin, and phytate contents ranged from 28.2-71.4, 38.8-51.5, and 269.6-293.0 mg/100 g DM, respectively. Except for a few varieties of oats, the molar ratios were below the critical values. Results showed that both the landraces and improved varieties studied are an excellent source of valuable nutrients. Thus, the production and utilization of this crop in a few geographical locations and communities should be further encouraged in the rest areas of the country to benefit from this underutilized but nutritious crop.

Premilling treatments effects on nutritional composition, antinutritional factors, and in vitro mineral bioavailability of the improved Assosa I sorghum variety (Sorghum bicolor L.).

Sorghum (Sorghum bicolor L.) is among the staple cereal crops in different parts of Ethiopia. However, the presence of antinutritional factors restricts the digestion of proteins and bioavailability different minerals. Therefore, this study investigates the premilling treatments effects on nutritional composition, antinutritional factors, and in vitro mineral bioavailability of the improved Assosa I sorghum variety grown in Benishangul-Gumuz Region, Ethiopia. The experiment was conducted in a completely randomized design with single factor of premilling treatments (control, washing, soaking, and malting). Among evaluated premilling treatments, malting showed significant (p < .05) increase in terms of crude fiber, utilizable carbohydrate, gross energy, and sodium contents. As compared to the raw sorghum, premilling treatments reduced antinutritional contents from 55.81 to 27.4 mg/100 g for tannin, 156.15 to 70.50 mg/100 g for phytates, and 29.9 to 3.22 mg/100 g for oxalate. The premilling techniques also significantly (p < .05) improved in vitro mineral bioavailability as compared to unprocessed sorghum grains. Among the premilling treatments, malting showed significant difference (p < .05) in terms of reduction of tannins, phytates, and oxalate contents with relatively higher mineral bioavailability. In order to enhance the food and nutritional value of sorghum particularly for children and lactating mothers, it is recommended to germinated the grains. Flour from germinated grain also can be used in combination with other nutrient-dense foods to formulate healthy diets for children and maternal nutrition.

Free radical scavenging capacity, antibacterial activity and essential oil composition of turmeric (Curcuma domestica) varieties grown in Ethiopia.

Turmeric is a known spice indispensable for food preparation and is reported to possess different chemical properties and biological activities. The objective of this study was to determine the effects of variety and type of extracts on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) reducing capacity, antibacterial activity, and chemical composition of essential oil from turmeric varieties cultivated in Ethiopia. The results from the statistical analysis revealed that the highest total curcuminoids content (6.81% m/m), essential oil (6.37% v/m), methanol extract (13.42% v/m) were obtained from Dame variety. On the other hand, the lowest curcuminoids (5.12% m/m), methanol extract (10.58% v/m) and essential oil (3.92% v/m) contents were obtained from HT3/2002 variety. Dame variety also had the highest total polyphenol content (97.55 mg GAE/g) and radical scavenging capacity (46.58 16 µg/mL) with the lowest IC50 value (23.05 µg/mL). Among the tested microorganisms with turmeric extracts, growth inhibition was observed against S. aureus. The results also indicated that three compounds, namely α-Turmerone (32.41 and 35.16%), ar-Turmerone (25.20 and 25.47%), and Curlone (17.98 and 18.19%) dominated 75% of the essential oil component in Dame and Bonga 51/71 varieties, respectively. In summary, the results of this study revealed that extracts from Dame variety have strong biological potential with desired antioxidant and antibacterial activities.

Phytochemical contents, antioxidant activity and functional properties of Raphanus sativus L, Eruca sativa L. and Hibiscus sabdariffa L. growing in Ethiopia.

Information on phytochemical contents, antioxidant activity and functional properties of underutilized plants Figl (Raphanus sativus L.), Girgir (Eruca sativa L.) and Karkade (Hibiscus sabdariffa L.) grown in Benishangul Gumuz, Ethiopia are limited. In view of this, leaves and roots of Figl, leaves of Girgir, calyces and seeds of Karkade were evaluated following standard analytical methods. The total flavonoids, total anthocyanins, ß-carotene and L-ascorbic acid contents were ranged: 5.28-35.97, 0.01-2.53, 0.15-0.42 and 0.28-1.49 (db mg/g), respectively. The total flavonoids content, total anthocyanins content and antioxidant capacity were high in the brown calyces of Karkade, but are low in the roots of Figl. The antioxidant activity of roots of Figl and seeds of Karkade were low. The effective inhibitory concentration (IC50) toward 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity demanded from brown calyces of Karkade was low and the IC50 was strong negatively correlated with ß-carotene and L-ascorbic acid contents (i.e., achieve IC50 with low amounts of these bioactive compounds). The ferric reducing antioxidant power was positively strong correlated with total flavonoids and anthocyanins content. The finding showed that calyces of Karkade can be used as a candidate to substitute synthetic antioxidants and food colorant in food, beverage and pharmaceutical industries because of their high antioxidant capacity, desired color and as a good source of phytochemicals. The study also showed that the leaves of Figl and Girgir were found to exhibit good sources of vitamin C, ß-carotene with low bulk density. Because of these properties, they can be regarded as good candidate to supplement micronutrients particularly for vulnerable groups like infants and young children.