• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.45-49
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• 2002

This study was conducted to enhance the value of chamnamul (Pimpinella brachycarpa (Komarov) $N_{AKAI}$) as an useful food resource. Hunter L, a, b values (lightness, redness, yellowness) of chamnamul leaf were 33.28$\pm$1.94, -10.98$\pm$0.74, 14.05$\pm$1.29 and shearing force was 2745.2g. Contents of tannin and dietary fiber were 100.9 mg%, 24.0% (freeze drying base). The minerals identified in chamnamul were Ca 7.85 g/kg, K 76.31 g/kg, Mg 4.78g/kg, Fe 0.35g/kg, Na 2.35 g/kg. Chamnamul kimchi was packed in polyethylene film (200g) and fermented at 2$0^{\circ}C$ and 4$^{\circ}C$. In color changes kimchi fermented at 2$0^{\circ}C$ showed more increase in Hunter L, a, b values than kimchi fermented at 4$^{\circ}C$. The pH of kimchi decreased and acidity increased with storage time at both temperature. Ascorbic acid contents decreased sharply with storage time. Loss of ascorbic acid contents was about 81.9% in kimchi fermented at 2$0^{\circ}C$ after 5 days, and kimchi fermented 4$^{\circ}C$ lost 77.3% of ascorbic acid after 30 days. Also reducing sugar contents decreased with storage time at 2$0^{\circ}C$ and 4$^{\circ}C$. The results of sensory evaluation showed that optimum ripening time of chamnamul kimchi was 1~3 days at 2$0^{\circ}C$ and more than 20 days at 4$^{\circ}C$.>.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.307-312
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• 1989

Internal mass transfer during osmotic dehydration of carrots in sugar solutions was examined as a function of concentration, temperature and immersion time of those solutions using moisture loss, sugar gain, molality and rate parameter. Influence of osmotic dehydration and blanching on browning reaction of vacuum dried carrots(3% MC: wet basis) was also evaluated. Increasing the concentration and temperature of sugar solutions increased moisture loss, sugar gain, molality and rate parameter. Water loss and sugar gain were rapid in first 4 min and then levelled off. The rate of sugar gain and molality changes on temperature was significant in lower concentration$(20^{\circ}\;Brix)$ compared to higher concentration$(60^{\circ}\;Brix)$. The changes of rate parameter were affected by concentration than by temperature of sugar solutions. Moisture loss during osmotic dehydration using a sugar solution $(60^{\circ}\;Brix,\;80^{\circ}C)$ with 20min immersion time was 55.7%. Effect of osmotic dehydration and blanching before vacuum dried to 3% MC(Wet basis) on browning reaction was significant. Minimum browning reaction during vacuum drying was carried out using pretreatments such as osmotic dehydration in sugar solution$(40^{\circ}\;Brix,\;80^{\circ}C)$ with 16 min immersion time(O.D.=0.09) and blanching with 12 min immersion time at $80^{\circ}C$(O.D.=0.31) compared to control(O.D.=1.59).

• Journal of the East Asian Society of Dietary Life
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• v.25 no.6
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• pp.1049-1057
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• 2015

This study investigated the physicochemical properties of Dioscorea batatas for improvement of biological activities during a three-step steaming process, steaming $120^{\circ}C$ for 30 min and hot air drying at $60^{\circ}C$ for 8 hrs. Samples were extracted with 70% ethanol and analyzed for free sugars, and organic acids were analyzed by HPLC. The DPPH & ABTS radical scavenging activities, crude saponin, water binding capacity, oil absorption, and ${\alpha}$-glucosidase activity were measured. The major free sugars in all samples were fructose, maltose, and sucrose, and the free sugar contents increased to 157~235% after the three-step steaming process compared to the control. Organic acid contents of samples treated by steaming increased to greater than 55.8 mg/100g. The ABTS radical scavenging activity significantly increased with repeated steaming process, especially after the three-step process. As the time of steaming process increased, DPPH radical scavenging activity increased from 26.99% fresh Dioscorea batatas to 80.46~97.79% after the three-step process. Crude saponin content increased rapidly as steaming time increased, but decreased after the three-step process steaming process. The water-binding capacities of the samples treated by steaming process were higher than that of the control, whereas oil absorption decreased as steaming time increased. From the results, steaming process could be suggested as beneficial for controlling fat intake. Compared to acarbose, a known antidiabetic drug, used as a positive control, ${\alpha}$-glucosidase inhibitory activity of samples treated by two-step steaming was among the samples. The results suggest that Dioscorea batatas treated by steaming process has antioxidative and anti-diabetis activities and can be used as a natural health product.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.776-784
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• 2016

In this study, green Larix kaempferi lumber was heat-treated by using superheated steam (SHS) at a pilot scale and then various physico-mechanical properties of the heat-treated wood were evaluated and compared with the properties of conventional hot air (HA) heat-treated wood. Decay resistance of brown rot fungi and compressive strength parallel to the grain of the SHS heat-treated wood without occurrence of drying check from green lumber were increased. On the other hand, density, equilibrium moisture content, shrinkage, and bending strength of the SHS heat-treated wood were lower than those of the conventional HA heat-treated wood. Because heat transfer and thermal hydrolysis of SHS heat treatment was accelerated by a large amount of water, the effect of SHS heat treatment on the physico-mechanical properties was higher than that of HA heat treatment at the similar conditions of temperature and time. From the results of this study, because green lumber can be heat-treated without occurrence of cracks or checks by using SHS and similar heat treatment effect on the physico-mechanical properties of wood can be produced despite a low temperature or short time of heat treatment, it is expected that heat time and energy consumption could be reduced by using SHS.

• Journal of the Korean Geotechnical Society
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• v.33 no.1
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• pp.57-65
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• 2017

During a construction of embankment, sub base, or retaining wall backfill, the speedy measurement of water content is necessary. In this study, a test method for field determination of water content of soil by the calcium carbide gas pressure (speedy water content measurement method) was evaluated for its reliability and accuracy. Dry oven and microwave oven methods were also used for water content measurement. In the test, weathered granite and Nakdong River sand in the site and kaolinite were used for water content measurement. The mass of 20, 22, 24, 26, 28, and 30 g of soil was respectively tested for 1, 3, and 5 min. The effect of each sample on water content was compared one another and analyzed. As the mass and testing time increased, the water content increased. The amount of soil was more important factor than testing time for the speedy water content measurement. In order to obtain similar result to that of dry oven method, 3 min of testing time with 24 g of soil was necessary for weathered granite classified as SM and 3 min with 30 g for Nakdong River sand classified as SP. For Nakdong River sand with 20-50% of kaolinite, the water content by speedy measurement increased as the clay content increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1799-1807
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• 2016

This study investigated the quality characteristics and antioxidant activities of espresso coffee prepared with green bean fermented by lactic acid bacteria. First, 10, 20, and 30% (w/v) green beans were fermented by Lactobacillus acidophilus KCTC 3145 at $37^{\circ}C$ for 0, 12, and 24 h, respectively. Cells of L. acidophilus gradually increased with increasing green bean content and fermentation time. After drying fermented green beans, coffee powders were prepared by roasting (city level) and grinding (<75 mesh). Then, espresso coffee was extracted using coffee powder. The pH and chromaticity (L*, a*, and b* values) of espresso coffee decreased with fermentation time, whereas total acidity, total soluble solid contents, and brown color intensity increased. The pH level decreased with increasing contents of fermented green bean and total acidity increased. However, chromaticity, total soluble solid contents, and brown color intensity remained within a limited range. The antioxidant activities, including total polyphenol content, and DPPH and ABTS radical scavenging activities increased with increasing green bean content and fermentation time. Finally, sensory evaluation -for taste, color, flavor, and overall preference- revealed espresso coffee prepared with fermentation of 30% (w/v) green bean received the highest scores. Green bean fermented by lactic acid bacteria enhanced quality characteristics and antioxidant activities of espresso coffee, showing that lactic acid bacteria fermentation has potential use in the espresso coffee industry.

• Applied Chemistry for Engineering
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• v.27 no.1
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• pp.39-44
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• 2016

This study was to investigate the characteristics of combustion toxic gases of pinus rigida specimens treated with chemical additives such as pyrophosphoric acid (PP)/ammonuium ion ($NH_4{^+}$), methylenepiperazinomethyl-bis-phosphonic acid (PIPEABP) and $PIPEABP/NH_4{^+}$. Each pinus rigida plates was painted in three times with 15 wt% of each chemical additives in the aqueous solution. After drying these specimens at room temperature, the production of combustion gases and smoke was examined by the cone calorimeter (ISO 5660-1). As a result, the peak mass loss rate time (PMLR time) treated with chemicals was delayed upto 10.5~47.4% compared to that of using untreated specimen. In addition, the peak production of carbon monoxide ($CO\;_{peak}$) of 32.1~71.4% and total smoke release rate (TSRR) of 15.6~43.6% for test pieces treated with the chemical additive were higher than that of using the virgin plate. In particular, for the specimens treated with the chemical additive, the rate of smoke release (RSR) 29.4~41.5% was obtained higher than that of untreated plate except the specimen treated with $PP/4NH_4{^+}$. It can thus be concluded that the treatment using the chemical additive could partially increase the combustion-retardation properties of the species when compared to those of the virgin plate.

• Fire Science and Engineering
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• v.27 no.6
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• pp.70-76
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• 2013

Four kinds of new piperazinomethyl-bis-phosphonic acid $M^{n+}$ ($PIPEABPM^{n+}$) were synthesized and their combustive properties of Pinus rigida plates treated with $PIPEABPM^{n+}$ were tested. Pinus rigida specimens were painted in three times with 15 wt% $PIPEABPM^{n+}$solutions at the room temperature. After drying specimen treated with chemicals, com-bustive properties were examined by the cone calorimeter (ISO 5660-1). As a result, the combustion-retardation proper-ties were increased by due to the treated $PIPEABPM^{n+}$ solutions in the virgin pinus rigida. Especially, the specimens treated with $PIPEABPM^{n+}$ showed both the lower peak heat release rate ($HRR_{peak}$) (162.02~145.36) s and total heat release rate (THRR) (73.0~67.4) $MJ/m^2$ than those of virgin piperazinomethyl-bis-phosphonic acid (PIPEABP)-plate. Compared with virgin PIPEABP-plate, the specimens treated with the $PIPEABPM^{n+}$ showed low combustive properties. However the specimens treated with $PIPEABPM^{n+}$ showed both the shorter time to ignition (TTI) (67~23) s and the time to flameout (Tf) (472~433) s than those of virgin PIPEABP-plate by increasing the thermal conductivity.

• Journal of the Korean Wood Science and Technology
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• v.29 no.1
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• pp.31-42
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• 2001

In this study, we obtained fundamental data about Korean raw lacquer's physical and chemical properties to produce high quality lacquer. The tested raw lacquers were obtained from Won-ju in Korea, Shanxishang, Guizhoushang, Anhuishang in China. The drying time of refining lacquers, tensile strengths of dried films and uniformity of films are measured. The refined lacquers were prepared by experimentally scaled refining equipment. Films of lacquer were applied on glasses by film applicator. This films were tested by universal strength test machine. The films were pictured by scanning electron microscopy and confocal microscopy to define the uniformity of them. The refining method were not different among three different kind of raw lacquers which were different their collecting time and places. But the viscosity of them were quite different. When black refined lacquer is made with iron powder, the adding time of iron powder is critical to control the viscosity of it. The refining times, viscosity and tensile strength of refined lacquers were not depended the method of refining condition but the place of collecting of raw lacquer.

• Journal of Sericultural and Entomological Science
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• v.26 no.2
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• pp.16-25
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• 1984

The sericin fixation of silk fabrics by epoxy resins was studied in the presence of aqueous salt solution in different solvents at the indicated temperature for the desired time. Heavy weight gains were obtained in the reaction with glycerol diglycidyl ether (EX-313) and ethylene glycol diglycidyl ether (EX-810) catalyzed by potassium thiocyanate in such solvents as carbon tetrachloride and p-chloroethylene. The obtained results were summarized as follows; 1) The tested resins were found similar in reaction behavior to silk fabric. The effect of fixation and weight gains was higher in EX-810 than EX-313. 2) The weight gains were increased with reaction time and temperature, and degumming ratio reached a constant value in 90 min at 70$^{\circ}C$. 3) The weight gains and the degumming ratio reached an equilibrium at 3-5% of epoxy concentration. 4) The weight gains were remarkably influenced and increased by the concentration of salt solution. The degumming ratio reached an equilibrium over 0.5N concentration of salt. 5) The weight gains were increased with the dipping time in gently-sloping. The degumming ratio reached an equilibrium over 15 min dipping. 6) The effect of sericin fixation of hydrophobic solvents, such as Carbon Tetrachloride, p-Chloroeth-ylene, Cyclohexane, Xylene and Toluene, was found suitable. 7) The effect of drying temperature was not remarkable on the weight gains and the degumming ratio. 8) There was a slight decrease in the moisture regain of sericin-fixed silk and it may be possible to maintain the moisture regain in the sericin-fixed silk by the epoxy resins. 9) The results on testing physical properties of sericin-fixed silk fabric were as follows; The crease recovery was almost not different from undegummed fabric, but inferior to degummed fabric. The tensile strength was improving in accordance with the effect of sericin fixation, either the elongation did.