• Journal of Biosystems Engineering
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• v.42 no.1
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• pp.56-61
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• 2017

Purpose: High energy requirement and long cooking time are limiting consumption of pigeon pea (Cajanus cajan), a nutritious food. This study was performed to estimate energy and time demand by different methods of cooking pigeon pea. Methods: Pigeon pea (150 g) was soaked in 2.0 L of water at ambient temperature ($29{\pm} 2^{\circ}C$) to determine hydration behavior. Cooking experiments were conducted using aluminum and pressure-cooking pots. Efficiency of cooking was evaluated using four types of cooking appliances (kerosene, liquefied petroleum gas (LPG), electric, and charcoal stoves). Normal (continuous heating until the food was satisfactorily cooked) and control (controlling the energy input to closely match the actual energy required) cooking were conducted. Energy requirement and duration of cooking were determined using standard procedures. Results: Soaking increased moisture content from 11.99 to 30.01% in 90 min, while water absorption rate decreased with soaking duration. In cooking 150 g of pigeon pea using kerosene stove, presoaked normal pressure-pot cooking method consumed the least energy (10 800 kJ) and time (205 min), while unsoaked normal cooking consumed the highest energy (18 450 kJ) and time (336 min). Using LPG stove, unsoaked normal cooking method required the highest energy (52 470 kJ), while presoaked control pressure-pot required the least energy (14 405 kJ). For electric stove, the lowest energy (15 560 kJ) and shortest duration (105 min) were recorded during control cooking of presoaked sample in the pressure-pot. Conclusions: Control cooking was not practicable using charcoal stove. Generally, kerosene stove consumed the least energy, while electric stove was found to have the shortest duration of cooking.

• The Korean Journal of Food And Nutrition
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• v.33 no.3
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• pp.299-308
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• 2020

This study investigated the quality characteristics of black soybean sediments to diversify the availability of soybean. The cooking method selected for black soybean sediment preparation was a pressure cooking process without soaking, considering the isoflavone content. The black soybean sediments were prepared by the addition of 0, 10, 30, 50 and 100% (w/w) black soybean. When 0% to 100% black soybean was added to the black soybean sediments, the moisture and crude protein contents increased from 53.17% to 54.41% and from 12.07% to 21.68%, respectively. The total isoflavone content of the black soybean sediments was increased from 2.69 ㎍/g to 696.09 ㎍/g, respectively, by the addition of black soybean. The anthocyanin content of the black soybean sediments ranged from 279.29 ㎍/g to 387.8 ㎍/g by the addition of black soybean. The total polyphenol content and the total flavonoid content of the black soybean sediments range from 1.72 mg/g to 2.00 mg/g and 0.89 mg/g to 0.92 mg/g, respectively, by the addition of black soybean. Given the isoflavones, total polyphenol, and anthocyanin content of the black soybean sediments, it is appropriate that the ratio of added black soybeans is at least 50% after the pressure-cooking process, regardless of soaking.

• Applied Biological Chemistry
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• v.40 no.3
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• pp.225-231
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• 1997

Optimization theory was applied to a native and two imported soybeans. Failure stress and stress relaxation curve was measured with rheometer, and color was measured by colorimeter. The effects of each soybean upon the tofu texture were expressed through a non-linear canonical regression model and trace plot. Compared to the other imported soybeans, native soybean produced a higher strength in tofu texture, and showed the positive increase in viscoelastic properties such as instantaneous stress, equilibrium stress and relaxation time, whereas it had no effect on whiteness from reference blend, represented that native soy-bean showed the individual strength upon the selected rheological texture properties. Higher soaking ability in native soybean was selected as a new response for the optimization mixture process, and it contributed positively to the rheological properties of tofu. New soaking process control system during processing and desirability for the mathematical model should be applied for a better mixture design in varieties of soybeans.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.3
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• pp.157-160
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• 1998

To find out the effects of humidification and hardening of rice (Oryza sativa L. cv. Ilpumbyeo) seeds on the germination, both normal and artificially aged seeds with 60% germination rate were humidified at 40, 60, and 80% RHs and $25^{\circ}C$ for five weeks or hydrated for 6, 12, 18, and 24 hours at $25^{\circ}C$ from one to five cycles for hardening. Relative humidity and duration of humidification did not affect the germination rate of normal seeds, while reduced the time to get 50% germination rate ($T_{50}$) by 1.0～1.6 days compared to that of normal seeds at $25^{\circ}C$. Aged seeds humidified at 40 and 60% RHs did not affect the germination rate and $T_{50}$ regardless of relative humidity and duration of treatment, while at 80% RH, the germination rate decreased and $T_{50}$ increased significantly with the duration of humidification. Hardening of normal seeds reduced $T_{50}$ by 0.7～1.1 days without changes in the germination rate. However, the germination rate and $T_{50}$ of aged seeds soaked in water for 6, 12, and 18 hours were similar regardless of soaking/drying cycles, while hardening of artificially aged seeds with 1～4 cycles in 24 hours soaking increased the germination rate by 11-16% and reduced $T_{50}$ by 1.4～2.0 days.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.4
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• pp.271-278
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• 2005

In order to study the catch situation of the octopus pot fishery in the coastal waters of Gangneung, catch quantities and weight per month and depth, the soaking time & loss of fishing gear were studied based on 62 fishing times (1 set consisted of 150 pots which is equivalent to 1 fishing time) over a period of 10 months from February to December 2003 using commercial fishing vessels and training ships. The monthly CPUE was generally high in the months of june - September, and during this period July showed the highest quantity (134g/pot, 19.21kg/haul). In consideration of the fact that octopus below the weight of 2kg is protected in foreign countries, the majority of the catch was small with 76% (486 octopuses) below 1kg. The octopus catch quantity was high in depth of more than 40m, and the average catch number per set of pots in depths of over 50m was the highest with 13 octopuses. CPUE(g/pot) was the highest at a depth of over 60m recording 101. In terms of catch quantity per soaking time (4-18 days) the highest was on the 7th day, and 13-18 days also recorded high catches, and this suggests the possibility of ghost - fishing with the loss of fishing gear. Loss of fishing gear was the highest in terms of loss frequency and amount at depths of 20-30m. Consequently, it seems that octopus pot fishing at depths of more than 30m would relieve friction with other types of fishing and increase fishing efficiency.

• Korean journal of food and cookery science
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• v.18 no.2
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• pp.129-135
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• 2002

The effects of adding green tea powder on the quality and storage characteristics of tofu were studied. As the addition of green tea powder increased, the moisture content of tofu was decreased but those of crude protein and the crude ash were increased. The addition of green tea powder increased the production of whey and consequently decreased the yield of tofu. At the beginning of storage, the pH of the tofu with green tea powder was increased, but decreased rapidly at the eighth day of storage. The pH of tofu-soaking solution was decreased during the storage period. The L and b values showed no significant changes but a value was increased during storage. Textural characteristics of tofu added with green tea powder also did not show significant changes during storage. Although the total plate counts and absorbances of soaking solution of tofu were increased during storage, the samples with 1.0% green tea powder had the lowest TPC (3.0$\times$10$\^$6/ CFU/ml) and the lowest absorbance (0.175) at the eighth day of storage.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.272-277
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• 2018

This research was conducted to elucidate the optimum conditions for the antibacterial activity of konjak jelly using the evolutionary operation-factorial design technique. In the first set of experiments, concentration of a coagulation agent, soaking liquid, and temperature of water were set to 0.4%, $0.6{\times}10^{-2}N$, and $65^{\circ}C$ as a central point, respectively. The highest antibacterial activity was acquired at E21, in which the number of bacteria was 1.25 log cfu/g. Because the code of changes in the main effect was (-), it could be decided that the central point of the first set was not the optimum point. Although antibacterial activity in the second set was improved, the values of the main effect were higher than that of changes in the mean effect. The central point of third set was concentration of coagulation agent 0.8%, concentration of soaking liquid $1.0{\times}10^{-2}N$, and temperature of water $65^{\circ}C$. It was found that the antibacterial activity of central point in the third set was highest among all the tested set. Further, all the necessary conditions were appropriate to reach the optimum condition. The antibacterial activity of the central point in third set was more than 1,000 times higher than that of E11, in first set.

• Korean Chemical Engineering Research
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• v.55 no.6
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• pp.791-797
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• 2017

In this study, we optimized a method of PEO-PPO-PEO block copolymer embedding, for solving non-specific protein and biomolecular adsorption and high hydrophobicic surface property, which is widely known as problems of poly (dimethylsiloxane) (PDMS) that has frequently been used in basic biological and its applied research. We assessed its surface modification by controlling the concentration of embedded block copolymer, water-soaking time, and recovery time as variables by contact angle measurements. In order to evaluate its antifouling ability, adsorption of FITC-BSA molecules was quantified. Furthermore, we generated oil-in-water (O/W) emulsion as a proof-of-concept experiment to confirm that the optimized surface modification works properly.

• Molecules and Cells
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• v.26 no.1
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• pp.81-86
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• 2008

RNA interference (RNAi) was performed on several essential genes in the pinewood nematode Bursaphelenchus xylophilus, which causes pine wilt disease. Double-stranded RNA (dsRNA) was delivered to larvae or adult worms by soaking, electroporation, or microinjection. Soaking and electroporation of L2-L3 stage worms in solutions containing dsRNA for essential genes induced over 25% lethality after 5 days, and gene-specific phenotypes were observed. This lethality agreed with significant reductions of the targeted transcripts, as assayed by reverse-transcription coupled with real time PCR. Microinjection was the most efficient route as measured by the hatching rate of F1 embryos, which was reduced by 46%. When adult worms were soaked in dsRNA, lethality was induced in the F1 larvae, revealing the persistence of knockdown phenotypes. The penetrance of the RNAi phenotypes for essential genes was relatively low but consistent, indicating that RNAi should be useful for studying the in vivo functions of B. xylophilus gene products.

• Korean Journal of Plant Resources
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• v.29 no.3
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• pp.347-354
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• 2016

The present study was performed to investigate the effects of the colchicine concentrations on chromosome doubling for producing of tetraploid plants of Codonopsis lanceolata, and its effect on plant morphology. A total of 180 individuals germinated from 16 treatment groups, were exposed to various concentrations (0.05-1.0% w/v) of colchicine for different soaking duration (3-24 hour). The highest numbers of tetraploid plants (3) were observed from the lowest concentration of colchicine (0.05%), and one (1) tetraploid plant was obtained from the 0.5% concentration group with a 6 hour treatment. However, no tetraploid individual was observed in any other treatment groups. The plant height of the diploid (18.1 ㎝) was slightly shorter than that of the tetraploid (13.4 ㎝). The fresh weight of the main root in the diploid (0.5 g) was four-fold higher than the tetraploid (2.2 g). The colchicine-treated plant regeneration rate in C. lanceolata was decreased when the plants were subjected to high concentration of colchicine. In particular, the highest number of tetraploid plants (5 and 3) was obtained from the lower concentration (0.05% and 0.1%) of colchicine for 6-hour treatment, which were a higher rate (29.4% and 30%) of regenerated tetraploid plants than other regenerated plants. As in the seed treatment result, the plant height of the diploid was significantly higher (10.4 ㎝) than tetraploid. The higher morphological changes were observed comparatively from tetraploid plants than the diploid.