Effect of Variety and Storage on the Tuber Quality of Potatoes Cultivated in the Eastern Highlands of Ethiopia

Eight potato varieties: five improved and released by Haramaya University and three from smallholders potato farmers variety (eastern Hararghe, Oromia, Ethiopia) were planted following cultural practices in RCBD with three replications to assess tuber quality and storage performance differences. Tubers were harvested in 2011. After curing at 15-18oC and relative humidity of 75-82% for one week, the tubers were separately stored at 8-160C and relative humidity of 69-83% for 20, 40, and 60 days in a ventilated storehouse in CRD with three replication per treatment. The results showed significant differences (P< 0.05) due to variety. Storage duration significantly reduced dry matter, specific gravity and amylose contents with no significant changes in ash, crude fibre, potassium and phosphorus contents. The highest dry matter, specific gravity, and amylose contents were obtained for the improved variety Chala whereas the lowest was for the farmers’ variety Jarso. The highest crude protein content was recorded for the farmers’ variety Mashenadima and the lowest was for the improved variety Zemen. The results revealed that potato tubers with superior physicochemical qualities, most of which are released varieties retained their qualities after storage for longer durations, whereas those with lower qualities could be stored only for shorter durations

Effect of Grain Tef (Eragrostis tef (Zucc.) Trotter) Flour Substitutions with Flaxseed on Mineral Content, Antioxidant Activity, Phytic Acid Content and Microbial Quality of Injera

There is an increased global interest in the food industry to develop and market functional foods in which scientific investigations are limited in Ethiopia. Tef injera functional character can be further enhanced by substitution with flaxseed which is known to bear functional ingredients (α-linolenic acid an ω-3 fatty acid, secoisolariciresinol diglycoside lignans, dietary fibre and proteins). Two flaxseed forms (whole and flour) and three flaxseed substitution levels (3%, 6% and 9% flaxseed) arranged in a factorial experimental design in three replications were cofermented to find out whole or flour and at what substitution level injera with better nutrient and functional potential can be processed. Tef injera (100%) was used as a control. Tef injera substituted with flaxseed (whole and flour) at 3%, 6% and 9% showed a significant (P<0.05) effect on minerals (except P), ferric ion reducing antioxidant power (FRAP), phytic acid and microbial quality of injera. With 9% flaxseed substitution FRAP, Zn and Ca contents  percentage increase were: 102, 110 and 16; whereas phytic acid and Fe decreased by 76 and 19, respectively from the control. Between 2 to 6 injera storage days, yeast-mould (2.27 to 3.93 log cfug-1) and total aerobic plate counts (ND to 3.77 log cfug-1) were lowest for 9% flaxseedsubstitution and highest for the control injera (2.85 to 4.08 log cfug-1 and 3.70 to 4.30 log cfug-1, respectively). Coliforms were not detected. Whole flaxseed substituted injera had high minerals, antioxidant and microbial stability than flour flaxseed substituted injera. Injera with high minerals (except iron) and antioxidant of improved microbial stability, low phytic acid contents can be processed by 9% flaxseed substitution

Malt quality of 4 barley (Hordeum vulgare L.) grain varieties grown under low severity of net blotch at Holetta, west Shewa, Ethiopia

Four malt barley varieties (Beka, HB 120, HB 52 and Holker) and 3 fungicide (propiconazole) spray intervals (7, 14, 21 day) and no spray control were arranged in a RCBD in 4 replications to assess net blotch (Pyrenophora teres) effect on malt quality. The varieties were grown at Holetta agricultural research center in 2005, on 12 m2 plot. Grain flour starch pasting and malt qualities were analyzed. Mash odour and colour were evaluated qualitatively. Significant differences (P < 0.05) in malt qualities were observed among varieties and also due to spray intervals in hot water extract (HWE, mean range = 76.6 to 79.7%). The varieties had a pasting- time and -temperature (Ti) of 4.7 to 5.0 min and 64.7 to 66.3°C, respectively. Peak, hot paste, cold paste, breakdown and setback  viscosities were ranged 276.5 to 314.9, 176.3 to 218.3, 294.1 to 333.2, 86.3 to 99.6 and 102.4 to 116.4 BU, respectively. The pasting curves indicate no amylo- or -waxy starches with evidence of no damage by sprout- induced a-amylase activity and spray intervals. The varieties Ti matches mashing temperature (64 to 65°C) used in malt barley brewing. Malts from these grain varieties were prepared under controlled conditions. Malt aroma and flavor was similar with industry malt of sugary sweet taste. Thousand-kernel malting weight loss (TKMWL) was 11 to 13% and is in the range for desirably modified barley grain on malting. The varieties had a malt protein 6.4 to 7.4% and free amino nitrogen (FAN) 124.4 to 140.0 mg/100 g malt (db). The diastatic tendency assessed using malted barley flour as sources of enzymes and refined wheat flour starch as a substrate (1:29) showed a reduction in peak viscosities (mean) of the substrate starch paste from 678.0 to 168.0 BU. The varieties did not show consistent quality requirements in all parameters. Beka and HB 120 were better than HB 52 and Holker in HWE and diastatic tendency. The FAN level was high among HB 120, HB 52 and Holker. The findings indicate that net blotch incidence and severity influenced HWE and filtration time.Key words: Diastatic tendency, malt extract, FAN, malt barley qualities, net blotch, propiconazole, starch flour pastin

Chemical quality of common beans as influenced by genotype and aluminium rates under two soil liming regimes

Soil acidity affects seed yield and crop quality negatively due to aluminium toxicity in most humid tropics where the crop is cultivated for food and cash income by smallholder farmers. This study was conducted to assess the effect of different exchangeable aluminium concentrations on bean chemical quality of two common bean genotypes grown on lime-treated and lime-untreated soils. Factorial combinations of five aluminium rates (0.0, 12.5, 25.0, 50.0, and 100.0 mg Al/ kg soil) and two common bean genotypes (New BILFA 58 and Roba 1) were laid out in a completely randomized design with three replications. For each treatment, four plants were raised per pot in the vegetation hall of Nekemte Soil Laboratory, western Ethiopia. The experiment was established in two sets: lime-treated soil and lime-untreated soil. The results revealed that aluminium toxicity caused major changes in the composition of the common beans. Significant differences (P < 0.01) were found among the different aluminium rates and between the two genotypes for bean crude protein, crude fibre, crude fat, and ash, carbohydrate, calcium, magnesium, and aluminium contents under both liming regimes. The interaction of aluminium and genotype also influenced most of the bean chemical quality attributes negatively. New BILFA 58 (acidic soil tolerant genotype) had better bean chemical quality attributes (except aluminium and condensed tannins contents) than Roba 1 (acidic soil sensitive genotype) under both liming regimes. On the average, lime application increased bean crude protein, crude fat, ash, and calcium contents by 4.1%, 20.7%, 7.9%, and 11.7%, respectively. However, it decreased bean crude fibre and aluminium contents. Bean carbohydrate and condensed tannin contents of the genotypes increased in response to increasing aluminium application under both liming regimes. The total ash, which is an indirect indicator of the mineral content of foodstuffs, was found to be higher for New BILFA 58 than Roba 1 under both liming regimes. In conclusion, the results of this study have demonstrated that increased soil aluminium contents have significant negative effects on common bean quality, but integrated use of tolerant genotypes and application of lime can simultaneously alleviate the problem of low yield and reduced bean nutritional quality of the crop.Keywords: Aluminium, proximate, Lime, soil, Phaseolusvulgari

Response to Soil Acidity of Common Bean Genotypes (Phaseolus vulgaris L.) Under Field Conditions at Nedjo, Western Ethiopia

Soil acidity has become a serious threat to crop production in most  highlands of Ethiopia in general and in the western part of the country in particular. A field experiment was conducted to evaluate soil acidity tolerant on 25 genotypes of common bean (Phaseolus vulgaris L.) on lime treated and untreated acid soils. The genotypes were evaluated based on morpho-agronomic parameters. Soil acidity had an effect on maturity, growth and yield of the tested genotypes. High significant(P<0.01) differences were observed among genotypes for days to maturity, leaf area index, plant height, number of pods per plant, pod length, hundred seed weight, grain yield, pod harvest index and harvest index in lime treated and untreated soils. Considerable variability exists among the genotypes tested based on the growth, and yield components measured for soil acidity tolerance. The genotypes gave higher yield and yield components when grown in lime treated soil than lime untreated with average yield reduction of 26% due to soil acidity effect. Relative grain yield was calculated as the ratio of grain yield in lime untreated to lime treated soil also showed higher significant differences among the tested genotypes. Genotypes such as Dimtu, new BILFA 58, Beshbesh, SER176, new BILFA51 and new BILFA 61 gave higher absolute and relative yield, whereas Dinknesh, Chore, Nasser and new BILFA 60 gave lower absolute grain and relative yield. Moreover, the great variability of 25 commonbean genotypes exhibited a good potential to screening large germplasm of common bean for soil acidity tolerance and develop a cultivar that are tolerant to soil acidity in the country. Keywords: Common bean, Genotypes, Lime, Soil acidity, Relative yiel

Bio-based smart materials for fish product packaging: a review

Conventional packaging offers protection, containment, communication, and convenience to packaged food. The most commonly used packaging materials are petrochemical-based plastics which generate massive wastes that persist for a long time in the environment after their use. Bio-based materials are the best option to replace this synthetic plastic. This review presents the importance of packaging fish products using polysaccharides, proteins, polyhydroxyalkanoates, polylactic acids, pullulan, and xanthan gums loaded with different nanofillers and bioactive molecules. Bio-based smart materials easily decompose into carbon dioxide, methane, water, and inorganic compounds. Biopolymers can be produced from natural biomass, bio-monomers, and microorganisms. These biopolymers demonstrate excellent physiochemical, thermal, and mechanical properties when mixed or alone as fish packaging materials. Integration of nanofillers and bioactive molecules improves mechanical, gas barrier, antioxidant and antimicrobial properties of bio-based materials. Bioactive molecules like anthocyanins, betalains, curcumin, and clove oil are sensitive to pH, temperature, light, and time. Bioactive molecules can be loaded into bio-based packaging materials to monitor the real-time freshness of fish products during storage. It is concluded that bio-based smart materials have the potential for fish packaging, do not harm the environment, and easily interact with nanofillers and bioactive molecules

Technology generation to dissemination:lessons learned from the tef improvement project

Indigenous crops also known as orphan crops are key contributors to food security, which is becoming increasingly vulnerable with the current trend of population growth and climate change. They have the major advantage that they fit well into the general socio-economic and ecological context of developing world agriculture. However, most indigenous crops did not benefit from the Green Revolution, which dramatically increased the yield of major crops such as wheat and rice. Here, we describe the Tef Improvement Project, which employs both conventional- and molecular-breeding techniques to improve tef\u2014an orphan crop important to the food security in the Horn of Africa, a region of the world with recurring devastating famines. We have established an efficient pipeline to bring improved tef lines from the laboratory to the farmers of Ethiopia. Of critical importance to the long-term success of this project is the cooperation among participants in Ethiopia and Switzerland, including donors, policy makers, research institutions, and farmers. Together, European and African scientists have developed a pipeline using breeding and genomic tools to improve the orphan crop tef and bring new cultivars to the farmers in Ethiopia. We highlight a new variety, Tesfa, developed in this pipeline and possessing a novel and desirable combination of traits. Tesfa\u2019s recent approval for release illustrates the success of the project and marks a milestone as it is the first variety (of many in the pipeline) to be released

Effect Of Different Nitrogen Fertilizer Rates On Yield And Yield Related Traits For Seven Durum Wheat ( Triticum Turgidum L. Var Durum) Cultivars Grown At Sinana, South Eastern Ethiopia

An experiment was conducted at Sinana district on farmers field to study the effects of different nitrogen fertilizer rates (0 = control, 23, 46 and 69 kg ha-1) on crop phenology, yield and yield related traits, nitrogen uptake parameters and grain protein content of seven durum wheat cultivars (Ude, CDSS93Y107, Ejersa, Bekelcha, CD94523, Cocorit71 and Inglize). The experimental site soil samples were analyzed and texture was clay, with organic matter of 4.5%, available P of 8.8 ppm, CEC of 27 cmol kg-1 and pH of 7.1 and total nitrogen content of 0.24%. The experiment was conducted in a Randomized Complete Block Design (RCBD) with three replications. The result showed that nitrogen rates and cultivars had significant effect on yield, yield related traits, nitrogen uptake parameters and protein content. The cultivars CD94523 (4989 kg ha-1), CDSS93Y107 (4923 kg ha-1) and Bekelcha (4605 kg ha-1) showed better grain yield performance at the highest rate of nitrogen (69 kg ha-1) application probably due to highest response of the cultivars and use efficiency to N fertilizer. At 46 kg ha-1 N rate application, cultivars (Ude, Ejersa, Cocorit 71 and Inglize) showed also high grain yield similar to grain yield of 69 kg ha-1 N application. The TKW and HLW of the cultivars were ranged 42.5-49.5 g and 78.5- 81.6 kg hL-1, respectively. Among cultivars, Ude and Bekelcha were superior for TKW. The HLW of Ude, CDSS93Y107, Ejersa and Bekelcha were significantly superior. Increased N rates up to 69 kg ha-1 had increased straw N uptake, grain N uptake and total N uptake and the lowest N uptake was for the control treatment. The grain protein content (12.5%, mb) had ranged from 10.2% (Inglize) to 13.4% (Ude, Ejersa and Bekelcha) (P > 0.05). The highest N rates resulted in 15% more grain protein content than the control treatment which is essential for pasta processing and better nutritional value

Iisolation and physicochemical characterization of cassava starches obtained from different regions of ethiopia

The chemical composition, amylose content and physicochemical properties of cassava (Manihot esculenta Crantz., Fam. Euphorbiaceae) starches obtained from different regions of Ethiopia were investigated. The proximate composition of the starches on dry weight basis were found to be 0.001 - 0.01% protein, 0.08 - 0.11% fat, 0.03 - 0.1% ash, and 85.7% - 87.5% starch. The amylose contents of cassava starches from Gamo Gofa, Illubabor and Wollega were estimated to be 16.1%, 21.1% and 18.9%, respectively. Scanning electron microscopy (SEM) showed spherical granules. Particle size analysis revealed granule size distribution with a mean particle size of 12.71 μm (Gamo Gofa) 14.34 μm (Illubabor) and 11.70 μm (Wollega). X-ray diffraction study of the starch displayed A-type pattern with a distinctive maximum peak at around 17.0° 2θ. The true average density of the starch was found to be 1.497 g/ml. Brabender viscosity of 6% starch paste showed peak viscosities of 198.5 BU (Gamo Gofa), 224.0 BU (Illubabor) and 208.0 BU (Wollega). Differential scanning calorimeter (DSC) parameters of native starch-water mixture (1:2) exhibited an onset temperature (To), a peak temperature (Tp) and an endset temperature (Te) of 60.19, 65.80, 71.53 (Gamo Gofa), 55.93, 60.80, 66.61 (Illubabor), and 58.29, 64.70, 72.47 (Wollega), with a corresponding gelatinization enthalpy (ΔH) of 21.04, 17.05, and 22.34 mJmg-1, respectively.Keywords: cassava starch, amylose content, X-ray diffraction, Brabender viscosity, gelatinizatio

Quality of grain maize stored in Gombisa and sacks in selected districts of Jimma Zone, Ethiopia

Quality  of  maize grains  (Variety:  Bako Hybrid-660,  BH-660)  stored  in two storage containers (Gombisa and Sacks) for 180 days was studied in two agro ecologies: intermediate (IAE)- and lowland (LAE) of Jimma zone, Ethiopia. Crude protein, crude fat, dry matter, total carbohydrate and ash contents were influenced significantly by storage periods in Gombisa (p<0.05). Crude fat under LAE and ash under both agro-ecologies were also influenced by storage days (p<0.05). There was a significant (p<0.05) effect of storage containers on dry matter and total carbohydrates in the IAE whereas in LAE appeared insignificant (p>0.05). Grains stored in Gombisa under IAE showed significantly lower dry matter and total carbohydrate contents than in Sacks. The study showed maize grain quality deteriorations in Gombisa because of favorable moisture, relative humidity and temperature conditions for maize weevil (Sitophillus zeamais) and angoumois grain moth (Sitotroga cerealella) attacks during 180 days of storage.Keywords: Agro-ecologies, Chemical composition, Gombisa, Maize grain   quality Sac