• Polymer(Korea)
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• v.24 no.5
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• pp.713-720
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• 2000

A polymer/iodine complex film was prepared using syndiotactic poly(vinyl alcohol) (s-PVA) with number-average degree of polymerization of 900 and syndiotactic diad content of 63.1%. In comparison with atactic-PVA/iodine films, degree of polarization of the s-PVA/iodine film was improved up to over 99% although a lower transmittance was obtained. By soaking in iodine/potassium iodide aqueous solution of a lower iodine concentration and subsequent drawing by 4 times, s-PVA/iodine film of a higher transmittance and degree of polarization was produced. The degree of iodine desorption of the s-PVA/iodine film in water were very low. The crystallinity and the d-spacing and crystal size of (100) plane increased at the early stage of soaking time, however, remained constant or decreased slightly with increasing soaking time. In consequence, s-PVA/iodine complex formation took place mainly inside crystal region at the initial stage of soaking time, whereas it occurred outside crystal region or physical adsorption of iodine dominated after sufficient soaking.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.732-737
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• 2005

The combinational effect of gamma irradiation and moist heating on the trypsin inhibitor activity (TIA) in soaked and dried soybeans was evaluated by measuring the inhibition using N-benzoyl-DL-arginine-p-nitroanilide (BAPNA) as substrate. Gamma irradiation significantly decreased the TIA level in soybean at doses above 5 kGy, and the $ID_{50}$ (the gamma irradiation dose required to reach 50% inhibition) value for TIA was 13.53 kGy. Soaking prior to gamma irradiation significantly lowered the $ID_{50}$ to 8.44 kGy, and the soaking process enhanced the efficiency to inactivate TIA by as much as 48%. When soaking prior to gamma irradiation was followed by subsequent mild heating ($60^{\circ}C$) process, the $IT_{50}$ (heating time required to reach the 50% inhibition of TIA) value at even 1 kGy (5.28 min) was greatly reduced by over 50% compared to the level for the no-soaking process. In addition, the activation energy of soaking prior to gamma irradiation at 1 kGy was 2.45 kcal/mole, which was also about 50% lower than the 5.10 kcal/mole of dried soybean gamma-irradiated. Based on these results, soaking prior to gamma irradiation is an effective method for TIA inhibition. Furthermore, a combination of two or more processing methods such as soaking, heating and gamma irradiation is much more effective than any single processing method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.752-757
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• 2000

Response surface methodology was used to optimized soaking and roasting conditions and monitor organoleptic properties of roasted Platycodon grandiflorum tea. In soaking and roasting processes based on the central composite design with variations in threonine/sucrose concentration for soaking of Platycodon grandiflorum, roasting temperature and roasting time, coefficients of determination ($R^2$) of the models were above 0.86(p<0.05) in organoleptic properties. The maximum conditions predicted for each corresponding organoleptic properties of roasted Platycodon grandiflorum tea were 1.64% threonine concentration, 137.83$^{\circ}C$ and 27.76 min in aroma, 1.46% threonine concentration, 136.1$0^{\circ}C$ and 25.19 min in taste, and 1.39% threonine concentration, 136.44$^{\circ}C$ and 29.05 min in overall flavour. The optimum condition ranges for organoleptic properties of roasted Platycodon grandiflorum tea were soaking in 1.40~1.64% threonine concentration, and roasting at 136.10~137.9$0^{\circ}C$ for 25.19~29.00 min.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.134-138
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• 2000

Most parts of alfalfa plant have been reported to contain autotoxic substances that inhibit seed germination and early seedling growth, however, the chemical(s) is not still studied much. Effect of seed leachates of 'Vernal' alfalfa (Medicago sativa L.) was evaluated for inhibition of alfalfa germination and root growth through bioassay. Alfalfa seeds were extracted in 1 L deionized water for 1 h after soaking and the leachates caused to reduce root length of alfalfa significantly as the soaking time increased. Crude seeds at 4 g L$L^{-1}$ exudated autotoxins that reduce significantly root length by 34 % compared to the control, when the seeds soaked in deionized water for 24 h. However, the extracts did not affect final germination as well as speed of germination. Extracts from ground seeds significantly reduced speed of germination (GT 50) and root length. The results indicate that release of autotoxic substances from seeds during seed imbibition was increased with increase of soaking time and seed amount, and that autotoxicity was more occurred in ground seeds than in crude seeds.

• Korean journal of food and cookery science
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• v.7 no.2
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• pp.25-40
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• 1991

Five-brown-rice-variety, Akibare, Odaebyeo, Taebaegbyeo, Nonglim Na 1 and Hankangchalbyeo, was prepared and examinated the hydration kinetics and the cooking qualities. Before the hydration the L/W ratio of raw Taebaegbyeo was the biggest value among the five brown rices. The water uptake was directly proportional to the square root of soaking time. During the hydration water uptake of high yielding brown rices was bigger than those of traditional brown rices among the nonglutenious varieties but waxy brown rices were not. Generally volume increase constant was directly proportional to the water uptake constant, which were different a little with brown rices was hydrated which was inversed proportional to the water uptake degree. According to the instrumental result using the rheometer of cooked brown rice with increased soaking times that was decreased the hardness and was increased the adhesiveness. The sensory evaluation test indicated that the hardness and the stickiness value of cooked brown rices were proper after 15-hour-soaking time and it was identical result to the instrumental result using the rheometer.

• Applied Science and Convergence Technology
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• v.27 no.2
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• pp.42-45
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• 2018

Photovoltaic and optoelectronic devices based on hybrid metal halide perovskites ($MAPbX_3$; $MA=CH_3NH_3{^+}$, $X=Cl^-$, $Br^-$, or $I^-$) are rapidly improving in power conversion efficiency. Also, during recent years, perovskite single crystals have emerged as promising materials for high-efficiency photovoltaic and optoelectronic devices because of their low defect density. Here we show that the light soaking effect of mixed halide perovskite ($MAPbBr_{3-x}I_x$) single crystals can be explained using photoluminescence, time-resolved photoluminescence, and Raman scattering measurements. Unlike Br-based single crystal, Br/I mixed single crystal show a strong light soaking effect under laser irradiation condition that was related to the existence of multiple phases.

• Journal of the Korean Home Economics Association
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• v.30 no.3
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• pp.101-117
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• 1992

Effects of gamma irradiation(2.5∼20kGy) on water absorption property was studied for a local variety of black soybeans. In water absorption patterns of black soybeans, the time to reach a fixed moisture content was reduced depending on the increment of water soaking temperature and irradiation dose. Irradiation at 2.5∼10kGy resulted in the reduction of soaking time of black soybeans by about 1∼3 hours and the increase of hydration capacity by 10∼20%, respectively, compared to the nonirradiated control black soybean. The water uptake rate constant of the irradiated black soybean difinitely increased with the increase of dose levels and water soaking temperature. The activation energy for water absorption and z-value were lower in the irradiated black soybeans than in the nonirradiated control black soybean. The efficacy of water absorption property in the irradiated black soybeans was also recognized after one year of storage at room temperature.

• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.247-251
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• 1993

Physico-chemical characteristics of glutinuous rice during soaking treatment at different temperature for Yu-Kwa (Korean traditional glutinous rice cake) processing were determined. Crude fat and protein contents of soaked glutinous rice decreased up to 30% to 50%, respectively, compared to raw rice, but there was a little difference in soaking periods. As the soaking period increased pH of soaking solution was decreased from 6.4 to 3.3, while Brix was increased from 0.5 to 13.6. Titration acidity of soaking solution and soaked rice were increased to 22.9 and 3.4, respectively, as the soaking period increased to 9 days at $20^{\circ}C$ soaking, but it was increased rapidly to 29.8 and 4.0, respectively, at $30^{\circ}C$. The three kinds of free sugar such as glucose, sucrose and maltose were detected. Glucose was the major produced free sugar during soaking, sucrose was not detected after 1 day soaking period. Characteristics of amylographic viscosity on soaked rice showed that there are no difference in pasting temperature by the soaking time and temperature, but the maximum viscosity was drastically increased on $1{\sim}2\;day$ soaking period and decreased rapidly after $2{\sim}3\;day$.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.927-935
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• 2005

The objectives of this study were to investigate the soaking properties of the high-dietary fiber rice 'Goami 2'and to develop korean white Gruel prepared with Goami 2. With increasing soaking time at room temperature ($20^{\circ}C$), the water absorbing character of Goami 2 and Ilpum significantly increased during the first hour of soaking time, after which it remained constant. On the contrary, the hardness of Goami 2 and Ilpum significantly decreased with increasing soaking time until one hour, after which it remained constant. The properties of Korean white gruel were evaluated using two varieties of rice (Goami 2, Ilpum) and three blending times (10, 20 and 30 seconds respectively). The rice flour of Goami 2 for Korean white gruel showed a greater number of small particles (<20 $\mu$m) than that of Ilpum. Hunter a'and b'values of Korean white gruel prepared with Goami 2 were higher than that of Korean white gruel prepared with Ilpum. The consistency values on Bostwick consistometer of Korean white gruel prepared with Goami 2 were higher than those of Korean white gruel prepared with Ilpum. The texture of Korean white gruel was examined using a back extrusion rig. All of the rheological parameters of Korean white gruel prepared with Goami 2 were decreased with increasing blending time, while in llpum they were increased. In the sensory evaluation results, the overall acceptability of korean white gruel prepared with Goami 2 blended for 20sec showed the highest sensory scores and desirability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.4
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• pp.401-406
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• 1983

Changes in the soluble sugar content contained in the soybean, soybean milk, soybean curd and soybean whey were determined to investigate the method of reducing the introductions of soluble oligosaccharides like sucrose, raffinose and stachyose, which cause flatulence in human, to soybean curd from soybean by extending the soaking time of soybean. The soybean curd yields according to the extention of the soaking time were also determined. Markedly increased glucose, slightly reduced fructose and sucrose and noticeably reduced raffinose in soybean milk were observed with extended soaking time. Most of sucrose, raffinose and all of maltose were transferred to soybean whey. Gradual increase of soybean curd yields were obtained by extending soaking time within the experimental conditions.