• Research in Plant Disease
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• v.13 no.2
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• pp.104-109
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• 2007

Pink root disease of onion, a known worldwide constraint upon onion production, significantly reduces crop levels in the main Korea cultivation area. In order to examine the effect of flooding on incidence of pink root disease caused by Pyrenochaeta terrestris and on onion growth and on populations of soil fungi, field experiments were conducted during two seasons, 2003/04 and 2004/05 at Onion Research Institute. Populations of soil fungi from fields were assayed on selective media. Flooding treatment was effective in reducing populations of P. terrestris, Pythium spp., and Rhizoctonia sp. in soil; fungal populations in soils flooded for 90 days were reduced to 1/2 to 1/3 of those in non-flooded soils. In nursery bed, protective activities of soils flooded for over 60 days were 93.5 to 99.2% and their pink root incidences were less than 5%, which were 1/11 to 1/18 of that in control. Increased yield of onion bulbs was associated with control of soil borne pathogenic fungi by flooding treatments. As flooding period was prolonged, bulb grade showed the tendency to increase. Soil flooding for over 60 days resulted in effective disease control, facilitated accurate planning of plant population in the field, extension of the growing-season and consequently higher yields of better quality.

• Food Science and Preservation
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• v.14 no.5
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• pp.504-510
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• 2007

An extrusion process was to make an onion kimchi snack from rice grit and onion kimchi powder, in an effort to enhance the nutritional value, flavor, and physicochemical properties of the extrudate. This study investigated optimum conditions (moisture content, barrel temperature, and the content of onion kimchi powder) for the production of high-quality rice extrudate products, and measured quality properties (water absorption index, texture, expansion ratio, and color) of rice extrudate to which onion kimchi powder had been added. Onion kimchi powder at 3%, 5%, 7%, and 10% (all w/w) was mixed with rice grit and the mixture then extruded in a twin-screw extruder. The texture of onion kimchi mack became softer as onion kimchi powder level rose, and water absorption ability increased. The expansion ratio and the lightness of extrudates decreased with increases in onion kimchi powder levels. The maximum water absorption index am the minimum hardness were obtained with 10% onion kimchi powder. Rice extrudate with 10% onion kimchi powder was suitable for extrusion cooking md obtained the highest score for overall acceptability by sensory evaluation.

• Journal of Life Science
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• v.27 no.12
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• pp.1430-1436
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• 2017

This study assessed the effects of treatment with sap extract from onion residues postharvest and purslane on the quality and quantity of organic onions. At the bending stage, onions treated with the sap extract showed vigorous growth, with higher plant heights, more leaves, and longer sheath lengths than untreated onions. The onion yield was significantly increased when the plant was treated with extracted sap as compared with that of untreated plants (p<0.05). The bulb weight distribution of onions in the mixed onion and purslane treatment was also significantly increased (~300 g) as compared with that of the other treatment (p<0.05). Except for CaO and S, the mineral content of the onions produced from plants treated with the onion and purslane extract mixture was higher than those of onions in the other treatment. The hardness of onions produced from plants treated with the onion and purslane extract was significantly increased (8% and 20%, respectively) as compared with that of onions produced from plants treated with the onion extract only or no treatment (p<0.05). However, there was no significant difference in the sugar contents of the onions produced from extract-treated and nonextract-treated plants. Postharvest, the content of inorganic components (phosphate, calcium, sulfuric acid, and manganese) was higher in soil treated with the onion extract than in soil treated with the onion and purslane extract and non-treated soil. It can be concluded that residues left after onion harvests and purslane extract can be used as natural and environmentally friendly materials for the cultivation of organic onions.

• Fashion & Textile Research Journal
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• v.3 no.1
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• pp.35-41
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• 2001

Dyeing properties of silk fabric with onion shell were studied by investigating the effect of dyeing conditions, such as concentration of onion shell, dyeing temperature, dyeing time and pH, on dye uptakes. And also the effects of mordants and mordanting methods or color change and dye uptakes were investigated. For the practical use, the various color fastness of dyed and mordanted fabric were evaluated. The color fastness was improved when Fe mordant was added.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.567-570
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• 1998

More than 100 isolates of Stemphylium obtained form leaf blight lesions of garlic (Allium sativum), onion (A. cepa) and leek (A. fistulosum) were identified as Stemphylium vesicarium (Wallr.) Simm. based on various morphological characteristics rather than S. botryosum Wallr. previously reported on those plants in Korea. In controlled inoculations, the pathogen induced the disease symptoms on leaves of garlic 7 days after inoculation. Onion and leek were also artificially infected by the fungus. This is the first report of S. vesicarium causing a leaf blight of garlic, onion and leek in Korea.

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.147-148
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• 2006

Relative phase distribution of onion epidermal cells was measured by using the relative phase microscope with inverse linear polarizing method. Decrease of relative phase distribution of onion epidermal cells was also investigated as the elapse of time. In decrease of relative phase distribution, relative phase of cell membrane in onion epidermal cells decreased radically as compared with that of cytoplasm.

• Food Science and Preservation
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• v.20 no.6
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• pp.894-898
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• 2013

This study was performed to provide the basic data for the prediction of the usefulness of onion with cold tolerance cultivated in Kangwon. The physicochemical properties and antioxidant activity of freeze-dried and hot-air-dried (40 and $60^{\circ}C$) onions were investigated. The moisture content of the raw onion was 90.55%. The crude protein and crude fat contents of the freeze-dried onions were slightly higher than those of the hot-air-dried onions ($40^{\circ}C$ and $60^{\circ}C$). As for the color values, the freeze-dried onion powder was highest in lightness (77.19), and the $60^{\circ}C$ hot air-dried onion was highest in redness (6.09) and yellowness (24.60). Moreover, the color difference (${\Delta}E$) between the freeze-dried and hot-air-dried ($40^{\circ}C$ and $60^{\circ}C$) onion powders was significant. The brown index was lower in the freeze-dried onion than in both hot-air-dried onions. The total phenol content and the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging activity of both hot-air-dried onions were higher than those of the freeze-dried onion. These results indicate that the freeze-drying methods protected the physicochemical properties of the onion powder, whereas the hot-air-drying method enhanced the antioxidant activity and the total phenol content of the onion powder.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.5
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• pp.677-683
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• 2012

The characteristics and preservation of sulgi added with 0, 1, 3, and 5% onion juice were investigated during storage at $4^{\circ}C$, $18^{\circ}C$, and $30^{\circ}C$. The pH of sulgi added with onion juice was lower than that of sulgi without onion juice and showed higher pH levels at $4^{\circ}C$ than at $18^{\circ}C$ or $30^{\circ}C$. Hardness of sulgi gradually decreased with higher volume of onion juice. Sulgi added with onion juice had higher values of lightness and yellowness than those of the control, whereas redness value was lower. Water activity of sulgi increased upon addition of onion juice. Further, addition of onion juice inhibited growth of aerobic bacteria and mold on sulgi, and the highest suppression of microbial growth was observed at $4^{\circ}C$ compared to other storage temperatures. In the sensory evaluation, color, flavor, after swallowing, and overall quality were all higher in sulgi containing 1% onion juice, but there were no significant differences compared to control sulgi. These results imply that addition of onion juice to sulgi has health and functional benefits and also extends the self-life of sulgi.

• Journal of Life Science
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• v.26 no.5
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• pp.563-570
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• 2016

Onion vinegar has an undesirable flavor and taste that results from alcohol and acetic acid production from fermentation. In this study, we have used onion vinegar to develop an onion vinegar beverage with better sensory quality. The objective of this study was to determine the optimum blending ratio by using response surface methods to produce an onion vinegar beverage containing Yuza (Citrus junos Sieb ex Tanaka). The optimal formula for a fermented onion beverage was determined using a central composite design by the response surface methodology. The independent variables were obtained by regression analysis of the reaction surface of brown sugar, apple extracts and Yuza extracts. The optimum mixing ratio for onion vinegar:water:brown sugar:apple extracts:Yuza extracts was 6.0:77.6:4.9:9.2:2.3 (w/w). The actual overall acceptance was 7.08 under optimum conditions, which was close to the maximum predicted value of 6.96. The concentration of phenolic compounds, total flavonoids, and quercetin present in the onion vinegar beverage was 14.8 mg/100 g, 2.6 mg/100 g and 1.4 mg/100 g, respectively. The onion vinegar beverage showed antimicrobial activity against Staphylococcus aureus, Escherichia coli, Salmonella typhimurium and Enterobacter aerogenes. It also showed antioxidant effects, with a DPPH radical inhibition rate of 18.2% and superoxide dismutase (SOD)-like activity of 11.5%. In conclusion, the onion vinegar beverage described here seems to have nutritional value and potential biological activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.368-371
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• 2001

This study was conducted to evaluate the effects of dietary onion supplementation on the growth rate and blood cholesterol level in finishing pigs. Sixty $Duroc\;{\times}\;Yorkshire\;{\times}\;Landrace$ pigs ($69.75{\pm}0.79kg$ average BW) were used in a 50 day growth assay. Dietary treatments included 1) corn-SBM (Con), 2) 1)+dietary onion rice bran 1.0% (ORB1), 3) 1)+dietary onion rice bran 2.0% (ORB2). For overall period, average daily weight gain and average daily feed intake were increased by the addition of dietary onion compared with Con (linear effect; p<0.01). Feed efficiency ratio was successfully improved by supplementation of dietary onion (linear effect; p<0.01). The total cholesterol concentrations in serum decreased as the concentration of onion in the diets was increased (linear effect, p<0.06). Also, LDL-cholesterol concentrations in serum tended to decrease in pigs fed onion than in those fed Con diet group (linear effect, p<0.04; quadratic effect, p<0.09). The HDL-cholesterol and triacylglyceride concentrations in serum were not influenced by the onion supplementation. The results obtained from this feeding trial suggest that the dietary onion supplementation for finishing pigs weighed 70 to 108 kg had improved growth performance and reduced total cholesterol level of serum.