• Korean journal of food and cookery science
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• v.9 no.3
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• pp.210-214
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• 1993

This investigation was undertaken for the purpose of studying the physicochemical properties of rice flour made by various soaking time(1,4,6,8,12 hours) of rice. As the soaking time was longer, the lightness of rice flours increased, on the contrary its redness and yellowness decreased. Rice flours had higher swelling power and solubility by increasing soaking time, but water binding capacity decreased upon soaking of rice. Hot water insoluble amylose of rice flours was decreased, whereas hot water soluble amylose was increased as the soaking time increased. The amylograph indices indicated that initial pasting temperature of rice flours decreased, while maximum viscosity increased as the soaking time increased.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.372-379
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• 2010

Macrophomina phaseolina causing charcoal rot was isolated from sesame seeds (cvs. Giza 32 and Shandawel-3) collected from different localities of Assiut, Sohage and El-Minia Governorates. The fungus was found in the highest frequently in samples collected from Assiut Governorate followed by Sohag and finally EL Minia Governorate. The obtained isolates were different in their virulence on the tested sesame cvs. Also, they differed in their growth nature including colony color and sclerotial production. The color of colonies of the pathogen seem to be correlated with density of sclerotial formation. Aqueous extracts of Majorna, Wild chamomile, Geranium oil and Nees plants were highly toxic to tested isolates of M. phaseolina, in vitro. On the other hand the rest of the tested aqueous extracts had no effect. Under greenhouse conditions in 2005 and 2006 seasons, soaking seeds of sesame before sowing in aqueous extracts of Eucalyptus, Nerium, Ocimum and Roesmary plants decreased the disease incidence. Aqueous extracts of Eucalyptus and Ocimum were the most effective treatment. Dipping sesame seeds in hot water at $60^{\circ}C$ for 5 minutes increased seed germination of Giza 32 and Shandawel-3 cvs. followed by $55^{\circ}C$, $50^{\circ}C$ and $45^{\circ}C$, while $40^{\circ}C$ treatment resulted the lowest seed germination rate. Dipping sesame seeds in hot water at different temperature before planting decreased seed, seedling and charcoal rots. Soaking seeds in hot water at $60^{\circ}C$ increased greatly plant height and decreased seed, seedling rot and charcoal rot followed by $55^{\circ}C$ and $50^{\circ}C$, under greenhouse condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.3
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• pp.320-326
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• 2009

The crops showing hard seed character have high seed viability after seed storage for long period. The low germination rate due to hard seed coat, however, cause a problem of low seedling establishment in field condition. Three legumes used in the experiment, lablab bean (Dolichos lablab L.), asparagus bean (Vigna sesquipedalis L. Fruwirth), and soybean (Glycine max L. Merr.), showed low germination rate (26, 17, and 5%, respectively) due to thick and hard seed coat. In this study artificial treatment for breaking dormancy was tested in hard seeds. The effect of proper treatment was various depending on species. The germination rate of lablab bean was highly improved up to 94% by soaking into water for 24 hours. In the case of asparagus bean, the rate was increased up to 90% by soaking for eight hours near boiling water until it cools. The germination rate of small hard seed soybean was increase to 96% by soaking into concentrated sulfuric acid for 10 minutes. Ultrastructural change revealed by scanning electron microscope (SEM) reflects that the structure of micropyle was changed and water uptake was facilitated with all treatments tested in the experiment. Especially, sulfuric acid treatment resulted in the degradation of micropylar tissue. These results demonstrate that the artificial treatment including sulfuric acid and (hot) water soaking treatment for promoting water uptake can be applied to improve seed germination in legume seed with thick and hard seed coat.

• Herbal Formula Science
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• v.7 no.1
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• pp.77-87
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• 1999

We studied medicinal theory on processing drugs of Wang-Ang. Wang-Ang used various methods of medicinal processing. He used such as soaking(浸), maceration(泡), washing(洗), elutriation(淘), mixing together(拌), refining powder with water(水飛) and floating(水漂) in medicinal processing with water. He used such as making hot(?), roasting in ashes(?), stir-frying with liquid(炙), parching(炒), heating(燒), baking(焙), stirring-baking(?) and distilling(煉) in medicinal processing with fire. He used such as steaming(蒸), boiling(煮), making hot and soaking(??) in medicinal processing with water and fire. And He used such as cooking(熟), making drugs into gelatin(制膠), making drugs into frostlike powder(制霜法), making drugs into bead(制珠), fermentation(生衣) and compound medicinal processing(複制法).

• Research in Plant Disease
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• v.14 no.3
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• pp.176-181
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• 2008

This experiment was conducted to find the causes of ineffective seed disinfection methods such as rice seeds soaking in hot water and prochloraz EC solution when the rice seeds were severely infected by Bakanae disease. In case of rice seeds collected from severely diseased field by Bakanae disease, the pathogen as the forms of spores and mycelium were infected in plumule and inner and outer integument of embryo, aleurone layer, and pericarp layer. When the rice seeds were soaked in hot water, the appearances of spores and hypha on the outer pericarp layer were severely disordered, however those of inner region of outer integument and aleurone layer were shown normal. The membrane of hypha on the outer pericarp layer was destroyed within 24 hours, while some spores were healthy and germinated 7 days after soaking, when the rice seeds soaked 24 hours in 125 ppm prochloraz solution at $30^{\circ}C$. These results indicated that the seed disinfection methods were ineffective on the Bakanae disease severely infected rice seed because the hot water did not transmit the pericarp layer of rice seed and also prochloraz solution did not effectively destroy the spore of pathogen.

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.682-689
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• 2015

A two-step process was investigated for pretreatment and fractionation of rice straw. The two-step fractionation process involves first, soaking rice straw in aqueous ammonia (SAA) in a batch reactor to recover lignin-rich hydrolysate. This is followed by a second-step treatment in a fixed-bed flow-through column reactor to recover xylo-oligomer-rich hydrolysate. The remaining glucan-rich solid cake is then subjected to an enzymatic process. In the first variant, SAA treatment in the first step dissolves lignin at moderate temperature (60 and $80^{\circ}C$), while in the second step, hot-water treatment is used for xylan removal at higher temperatures ($150{\sim}210^{\circ}C$). Under optimal conditions ($190^{\circ}C$ reaction temperature, 30 min reaction time, 5.0 ml/min flow rate, and 2.3 MPa reaction pressure), the SAA-hot-water fractionation removed 79.2% of the lignin and 63.4% of the xylan. In the second variant, SAA was followed by treatment with dilute sulfuric acid. With this process, optimal treatment conditions for effective fractionation of xylo-oligomer were found to be $80^{\circ}C$, 12 h reaction time, solid-to-liquid ratio of 1:12 in the first step; and 5.0 ml $H_2SO_4/min$, $170^{\circ}C$, and 2.3 MPa in the second step. After this two-step fractionation process, 85.4% lignin removal and 78.9% xylan removal (26.8% xylan recovery) were achieved. Use of the optimized second variant of the two-step fractionation process (SAA and $H_2SO_4$) resulted in enhanced enzymatic digestibility of the treated solid (99% glucan digestibility) with 15 FPU (filter paper unit) of CTec2 (cellulase)/g-glucan of enzyme loading, which was higher than 92% in the two-step fractionation process (SAA and hot-water).

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.312-312
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• 2017

The study was conducted to select optimal materials for promoting germination rate, high sprouting vigor by priming treatment using PEG 6000 (water potential -0.5 to 2.0 Mpa) and Azolla extracts (0.1, 1.0, and 10.0%) extracted by ethanol, distilled, and/or hot water in colored rice cultivars. Each rice seed (three black rice cultivars and two red rice cultivars) was soaked 24 and 48 hr including untreated control. In black rice, Joseongheugchal rice cultivar, azolla ethanol extract (0.1%) induced highest germination rate, germination speed was taken to 5 days in distilled water and to 3days in Azolla extracts extracted hot water. Otherwise, degree of bacterial inhibition (number of colony, $10^3cfu$) in dry seed, water soaking for 24hr, soaking with fungicide for 24hr and 48hr, soaking with fungicide and aeration for 24hr and 48 hr was 22, 500, 95, and 0.46, respectively. In order to minimize fungal inhibition, a method can be chosen to combination of soaking fungicide and aeration for 48 hr. In seed priming treatments using growth pouch, seed soaking with fungicide did not affect change of germination percentage and germination speed, it delayed only 2 or 4day in the Joseongheugchal rice cultivar. It differs from rice cultivars and priming materials, Azolla extract(0.1 to 1%) promotes seed germination percentage in the Ilpum, Hongjinju, and Joseonghuegchal, in addition, germination in Jeogjinju cultivar was only promoted by PEG solution(10 to 20%), otherwise, it showed much lower or inhibited on the germination in Heugjinju and Sinmyungheugchal rice cultivars. In a paddy field trial, seedling establishment rate by applying PEG6000 and azolla extract did not show significantly statistical difference. When it compared with untreated control, seedling establishment rate was increased over 50% in priming treatments. Interestingly, seedling establishment rate under azolla extract (0.1%) extracted with ethanol was promoted over 2.5 times compared to the control in a black rice, Joseongheugchal and red rice, Jeogjinju.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.345-355
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• 2017

This study was conducted to evaluate rice seed disinfection efficacy of loess-sulfur for the suppression of Bakanae disease caused by Fusarium fujikuroi. Rice seeds were treated at different concentrations of loess-sulfur, soaking time and temperature, and combination of hot-water treatment. Rice cultivar, Shindongjin harvested from Bakanae disease-infested area in 2015, was used. Loess-sulfur was treated as follows; concentration of undiluted solution, 2%, 1% and 0.5%; soaking time of 24 and 48 hours; treatment temperature of $20^{\circ}C$ and $30^{\circ}C$; hot water treatment or not. Optimal conditions of rice seed disinfection were selected soaking time of 48 hours and the suspension of 0.5% and 1% loess-sulfur by investigating seed germination and isolation frequency of Fusarium spp. on Komada agar medium in vitro, and were established 3 disinfection conditions as hot water ($60^{\circ}C$, 10 min.) + 1% loess-sulfur ($20^{\circ}C$, 48 hours), 1% loess-sulfur only ($30^{\circ}C$, 48 hours) and 1% loess-sulfur only ($20^{\circ}C$, 48 hours) through additional test in greenhouse. Above 3 conditions were verified by rice seedling box and paddy field test in the way of investigating Bakanae diseased plants (%) and healthy plants (%). Consequently, most effective rice seed disinfection conditions on Bakanae disease were combination of hot water and 1% loess-sulfur and loess-sulfur only at $30^{\circ}C$. Furthermore, treatments with these conditions showed control value of 100% were maintained from seedling to the heading stage in the field. However, treatment of 1% loess-sulfur only at $20^{\circ}C$ showed low control value of 78.2% in paddy field. Hot water only treatment turned out to be an effective disinfection method when conducted thoroughly with $60^{\circ}C$, 10 min. However, it was thought additional soaking process with loess-sulfur after hot water treatment served more high control effect against Bakanae disease when rice seeds were disinfected on a large scale. This results expected rice seed disinfection with loess-sulfur were effectively and easily usable method if farmers had only one of either hot water-disinfector or seed-disinfector. In addition, loess-sulfur is well-known to farmers, simple to manufacture method and cheap.

• Korean journal of food and cookery science
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• v.24 no.2
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• pp.188-197
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• 2008

This study was carried out to determine the optimal cooking conditions for various rice cultivars (Ilpoom, Saechucheong, Sindongjin, and Sura-top rice) using trial preparations with different soaking times (0, 30, and l20min) and cooking equipment (electric pressure cookers, electric cookers, gas pressure cookers, iron pots, and stone pots). In adddition, the texture and sensory characteristics of the rice prepared with the electric pressure cookers, gas pressure cookers, and stone pots were analyed. The results showed that the moisture, amylose and physicochemical compositions of the four rice varieties were similar. According to RVA, the Sura, cultivar had generally high viscosity, and the Ilpoom, cultivar presented the highest hot and peak viscosities. Saechucung had the highest initial gelatinizing temperature and Sindongjin showed the greatest setback. The optimal amounts of added water as well as heating conditons were dependent on the rice varieties, soaking times, and cooking equipment. A longer soaking time reduced the hardness of the cooked rice, amount of added water, and the heating time. The pressure cooking equipment provided the best cooked rice texture, reduced the affect of the soaking time, and decreased the heating time. In general, all the variaties of cooked rice had high overall acceptability, which tended to increase when the rice was soaked for 30min prior to cooking, had a 1.2-fold amount of water to rice added, and was cooked in the pressure equipment.

• Journal of Korean Society of Forest Science
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• v.60 no.1
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• pp.30-36
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• 1983

Plywood, the representative interior decorative or structural material, is so inflammable that it may cause big fires. Therefore, it is required inevitably to manufacture the "Fire retardant treated plywood", and it will be a study on the redrying of treated plywood that we ought to solve. This study was carried out to investigate the absorption of 20% $(NH_4)_2HPO_4$ solution into the soaked plywoods by hot/cold soaking for 3/3, 6/3, 9/3 and 12/3 hours and to study drying process with drying curves and drying rates by press-drying at the platen temperature of 130, 145, 160 and $175^{\circ}C$. Solution absorption of plywoods in hot/cold soaking method increased steadily with the prolonged soaking time, and water absorption is higher than DAP absorption, and then chemical retention (DAP) exceeded the minimum retention [$1.125kg/(30cm)^3$] even in the shortest soaking treatment. Drying curves of water-soaked plywoods inclined more steeply than those of DAP soaked plywoods. And the drying proceeded rapidly with the increase in platen temperature and terminated in 2.5-4 minutes at the temperature of 160 and $170^{\circ}C$. Drying rate also increased generally with the increase of platen temperature. So it was at $175^{\circ}C$ in DAP-soaking and at $160^{\circ}C$ in water-soaking when the drying rate became above 10%/min.