• Journal of Hydrogen and New Energy
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• v.33 no.4
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• pp.330-336
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• 2022

In order to evaluate the possibility as a separator in alkaline water electrolysis, the high temperature characteristics were evaluated by measuring the membrane resistance and durability of 5 types of commercial anion exchange membranes in 7 M KOH solution and at 80℃. The membrane resistance of AEM membrane measured in 7 M KOH solution and at 80℃ had a lower value of about 8-24 times compared to the other membranes. The durability of AEM membrane tested with the soaking time in 7 M KOH solution and at 80℃ showed a very good stability and that of FAAM40 and FAAM75-PK showed secondly a good stability. The thermal stability with the soaking time in 7 M KOH solution and at 80℃ of FAAM40 and FAAM75-PK membrane analyzed by thermo-gravimetric analysis showed a good stability compared to the other membranes.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.737-744
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• 2001

This study was carried to investigate the changes in physical and chemical properties during preparation of Yukwa. Protein content of glutinous rice was decreased during soaking time and acid and pH values were increased while contents of lipid and ash were not changed. Particle size distribution showed thate average particle size of 7 days soaking treatment smaller than those of 3 days and starch damage of glutinous rice flour was increased during soaking time. The major flavor components after soaking were found ethyl ester acetic acid, ethanol, 2-butan -ol, 2-methyl 1-propanol, 1-butanol, 3-methyl 1-butanol and 1-pentanol, propanoic acid. Content of acetic acid and butanoic acid were rapidly increased during soaking time. Results for ratio of storage modulus(G') and loss modulus(G') in glutinous rice flour dough indicated $tan{\delta}$ was increased for a while and decreased as frequency increased. G' value was very similar with G' value after steaming which means rubber-like property while G' and G' value were changed after during storage time. Treatment at $-20^{\circ}C$ had the highest hardness for cutting degree of dough. There was no difference in color value between different water contents. Hardness of Bandegi (sheet) was decreased as water content increased and the highest popping value was obtained at 18% of water contents. Adding 3% soaked bean had higher redness value of Yukwa and lower value in yellowness.

• Journal of Korean Society of Forest Science
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• v.44 no.1
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• pp.26-35
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• 1979

Factors affecting the survival of out planted Cryptomena and Japaneses Cypress seedlings. (I) - Especially on the drying and water soaking duration ­ There are often the cases of poor survival percentage for the economic forest establishments of Cryplomeria japonica D. Don. and Chamaecyparis obtusa End. This study was carried out to investigate the survival factors of both 1-1 seedlings and Cryptomena cutting Seedlings by room drying conditions, day drying conditions, OED green water soaking treatment and drying duration at the forest nursery of Chonnam National University from February to September. 1979. The results are as follows: 1. From 11 a.m. to 3 p.m. fluctuation in then moisture contents(MC) rapidly decreased and M.C. fluctuation in indoor until 5 p.m. showed the same results with the amount of an hour fluctuation in outdoor. 2. M.C. fluctuations between OED green and non-treatment of these seedlings were silghtly different. 3. The survival percentage of OED green and non-treatment of seedlings were highly significant in the room drying conditions and the day drying conditions respectively The effects of water soaking treatment on rooting was negligible. The survival percentage of seedlings of OED green was higher than that of non-treatment. 4. Although survival percentage of Japanese Cypress was almost in accord with Cryptomena, the power of resistance to drying was lower m Japanese Cypress than m Cryptomeria. 5. Compared with Cryptomena seedlings the survival percentage of Cryptomeria cutting seedlings was higher and not influenced at all in case of being drying for two hours; but it was highly significant in interactions between the drying time and the water soaking time. 6. When Cryptomena and Japanese Cypress seedling become drying in indoor for four days, the survival percentage remarkably reduced after two days and also was highly significant among numbers of drying days.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.268-275
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• 2004

Effects of soaking time and particle size on physicochemical properties of nonwaxy rice flour were investigated. Nonwaxy rice grains were soaked at $4^{\circ}C$ for 0, 1, 12, and 24 hr, dried at room temperature, and milled, Resulting flours were passed through 45-mesh ($<355{\mu}m,\;IL45$) and 100-mesh ($<150{\mu}m\;IL100$) sieves and separated into $<40{\mu}m\;and\;40-100{\mu}m$ series. IL45 series showed higher amount of large particles ($40-100{\mu}m$) than IL100 series. As the soaking time increased, protein and ash contents decreased, and amylose content, water-binding capacity, swelling power, and solubity of nonwaxy rice flours increased. Swelling power and solibility of nonwaxy rice flours also increased between $65-85^{\circ}C$. Water-binding capacity, swelling power, and solubility of IL100 series were higher than those of IL45 series. 12 hr-soaked nonwaxy rice flour pastes showed higher peak viscosity and breakdown but lower setback and visicosity at $95\;and\;50^{\circ}C$ than 1 hr-soaked ones. X-Ray diffractograms of nonwaxy rice flours were not affected, whereas surface appearance was affected, by soaking time and particle size.

• Food Engineering Progress
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• v.13 no.4
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• pp.235-242
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• 2009

The purpose of this study is to establish fundamental research data for quality characteristics of Jochung by analyzing traditional manufacturing process. Two different processed rices (non-glutinous rices cooked by steaming and using an electronic rice cooker) were compared in terms of water solubility index (WSI), water absorption index (WAI), paste viscosity, reducing suger content, solid content, and dextrose equivalent over soaking time. Reducing sugar content increased for the soaked non-glutinous rice, steamed sample and microwaved sample. After 4 hr, the WSI decreased as the soaking time increased. However, there was no significant difference between WAI of the raw non-glutinous rice and the soaked non-glutinous rice. As soaking time increased, paste and breakdown viscosity increased significantly. Rice was prepared by soaking in water for 12 hr followed by the saccharification time (4, 8, or 12 h) for manufacturing Jochung. The solid content and reducing sugar content of the Jochung increased as the soaking time increased. Reducing sugar content and dextrose equivalent of Jochung from steamed rice (cooked hard) were higher than those from microwaved ones. The amount of reducing sugar and dextrose equivalent was highest in Jochung from steamed rice cooked hard (saccarification for 12 hr), with 59.40${\pm}$0.11% and 76.99${\pm}$1.78, respectively. In conclusion, the highest quality characteristics were obtained in Jochung manufactured with non-glutinous rice soaked for 12 hr followed by sacharification for 12 hr.

• Korean Journal of Food Science and Technology
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• v.53 no.4
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• pp.486-494
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• 2021

A rice (Oryza sativa L.) cultivar of the SPP (stakeholder participatory program) and ordinary rice were characterized based on water-absorption properties and cooked rice texture. During rice soaking, the rice grain transformed from transparent to opaque (white), indicating that water molecules diffused into the rice grain during soaking. In addition, cracks in the internal structure of soaked rice gradually increased with an increase in soaking time. Water absorption increased rapidly up to 20 min, but no increment was observed after 30 min of soaking. At this point, the entire areas of the soaked rice grain turned white, indicating that water absorption had reached saturation. SPP rice showed lower hardness and higher stickiness in its cooked form than ordinary rice, suggesting that SPP rice could be a more preferable choice than ordinary rice. Furthermore, cooked SPP rice was more edible in terms of hardness and stickiness after being kept warm for 12 h than ordinary rice. These results indicated that cooked SPP rice exhibited slow retrogradation and improved taste.

• Journal of Life Science
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• v.19 no.4
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• pp.486-491
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• 2009

This study was conducted to investigate microbial distribution in the processing steps and to estimate quality index and shelf life of packaged Tofu (soybean curd). Sanitation and safety of Tofu were analysed in aspects of total viable counts (TVCs) and coliforms. Organoleptic deterioration was observed from some packaged Tofu when their TVCs were over $10^6\;CFU/g$. The controlled simply packaged Tofu and sterilized Tofu with TVCs of under $10^5\;CFU/g$ were 32.0% and 86.9% of the total samples, respectively. Also, the controlled simply packaged Tofu and sterilized Tofu with negative coliforms were 12.0% and 83.7% of the total samples, respectively. TVCs and coliforms increased in some processing steps, which include washing and soaking of raw soybeans, and formation and 1st cooling of packaged Tofu. Increases of TVCs and coliforms in the washing and soaking step were due to contamination from the soaking tank and airborne bacteria, whereas increases of TVCs and coliforms in the grinding step were due to contaminations from the grinder, line and reserving tank. TVCs and coliforms increased in the formation and 1st cooling step of packaged Tofu due to contaminations from filter wools, trays, employee's hands, cooling water, formed products and filter wools.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.4
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• pp.439-442
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• 2013

This study was conducted to develop the testing method for excessive water tolerance at germinating stage and to screen 31 domestic peanut cultivars. Regardless of peanut grain scales, the amount of seed absorption nearly reached the peak in 10 hours after imbibition. When peanut seed in vermiculate soil was directly soaked in water, ability of emergence did not reduced until 16 days and then sharply reduce to 25 days with non-emergence. When seeds germinated for 1, 2, 3, and 4 days after seeding (DAS) were soaked, the emergence abilities were distinctively varied according to the sequent soaking days such as 1, 2, 3, 4, and 5 days. This explained the negative relationship between first germinating days (DAS) and following soaking days. Using the method of 2 day germinating and 3 day soaking that show less than 70% of emergence ability, 31 peanut cultivars were applied to test excessive water tolerance. Emergence rates varied 0% to 69% according to cultivar. Cultivar Daekwang, Sinkwang, Daecheong and Baekseon had over 50% emergence rates. These results suggested that the degree of water resistance in germinating stage may be important point to evaluate the excessive water resistance among cultivars.

• Korean Chemical Engineering Research
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• v.52 no.6
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• pp.807-813
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• 2014

The Ag-impregnated activated carbon was produced from bamboo activated carbon by soaking method of silver nitrate solution. The carbonization and activation of raw material was conducted at $900^{\circ}C$. Soaking conditions are the variation of silver nitrate solution concentration (0.002~0.1 mol/L) and soaking time (maximum 24 h). The specific surface area and pore size distribution of the prepared activated carbons were measured. Also, NO and activated carbon reaction were conducted in a thermogravimetric analyzer in order to use for de-NOx agents of used activated carbon. Carbon-NO reactions were carried out with respect to reaction temperature ($20{\sim}850^{\circ}C$) and NO gas partial pressure (0.1~1.8 kPa). As results, Ag amounts are saturated within 2h, Ag amounts increased 1.95 mg Ag/g (0.2%)~ 88.70 mg Ag/g (8.87%) with the concentration of silver nitrate solution in the range of 0.002~0.1 mol/L. The specific volume and surface area of bamboo activated carbon of impregnated with 0.2% silver were maximum, but decreased with increasing Ag amounts of activated carbon due to pore blocking. In NO reaction, the reaction rate of impregnated bamboo activated carbon was retarded as compare with that of bamboo activated carbon. Measured reaction orders of NO concentration and activation energy were 0.63[BA], 0.69l[BA(Ag)] and 80.5 kJ/mol[BA], 66.4 kJ/mol[BA(Ag)], respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1364-1373
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• 2015

The purpose of this study was to determine the optimum sodium concentration (0~8%), soaking time (4~20 min) and storage time (0~60 day) for preparation of persimmon jangachi with kochujang sauce using response surface methodology. Physicochemical properties (salinity, pH, Hunter's color value, cutting force, and sensory evaluation) of persimmon kochujang jangachi were analyzed during storage at $20^{\circ}C$ for 60 days. When the proximate composition of persimmon was analyzed, moisture content, crude protein content, crude lipid content, and crude ash content were 85.41%, 0.51%, 0.22%, and 0.20%, respectively. For persimmon kochujang jangachi manufactured with different sodium concentrations, soaking times, and storage times, salinity, pH, Hunter's color value of L, a, and b, color, flavor, taste, texture, and overall preference were represented by a quadratic model. Cutting force was represented by a linear model pattern. In conclusion, the optimal formulation for persimmon kochujang jangachi, as assessed by numerical and graphical optimization methods, was a sodium concentration of 6.91%, soaking time of 11.36 minutes, and storage time of 25.18 days.