• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.285-292
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• 1999

An analytical method applicable to quality control and its optimum conditions were studied for rapid and efficient analysis of sorbic and benzoic acids used as preservatives in the commercial soybean paste. In gas chromatographic analysis of sorbic and benzoic acids, the application of HP-FFAP (acid modified polyethylene) wide bore column improved the separation ability significantly. By setting the oven temperature of GC to $200^{\circ}C$, the total elapsed time for quantitative analysis was also reduced to the level required in using packed column. By extracting sorbic and benzoic acids from soybean paste with an automatic steam distillation device, the elapsed time for analysis was reduced by 80% more compared to using conventional steam distillation method. The recoveries of sorbic and benzoic acids by the automatic steam distillation were 98.1% and 99.9%, respectively. The sorbic acid was found in 3 samples of 14 commercial soybean pastes, of which contents were $466{\sim}530ppm$, while $0.3{\sim}4.4ppm$ of benzoic acid was found in all the samples.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.786-791
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• 2007

Korean high speed train(HSR-350x) has adopted a combined electrical and mechanical(friction) braking system. Brake blending control unit(BBCU) controls each brake system to fulfill the required brake performances such as braking distance, deceleration and jerk. Also the braking system should be designed considering the economical management, such as effective use of generated braking energy and the minimum wear of friction materials(a pad and a brake shoe). In this paper, we establish the disc braking force pattern that reduces the wear of pad in the disc braking system by minimizing the variance of the instantaneous disk baking energy during braking time, and compare the wear mass of pad between the conventional disc braking force pattern and the established results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.914-920
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• 2008

In this study, hard roll breads were prepared with 3, 6, 9, 12, and 15% of concentrated sweet pumpkin powder (CSPP). The samples and a control were then compared in terms of quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, external and internal surface appearances, and sensory qualities of bread in order to determine the optimal ratio of CSPP in the formulation. As CSPP content increased, pH of dough, specific volume, baking loss, and lightness of bread decreased, while total titratable acidity of dough, pH, total titratable acidity, moisture content, and redness of bread increased. Fermentation power of dough expansion increased as incubation time increased. The CSPP samples had significantly higher yellowness, hardness, cohesiveness, gumminess, chewiness, and resilience than the control group. Adhesiveness was the highest at the 12% substitution level, while the lowest at the 6% level. Springiness increased with increasing CSPP content. In the sensory evaluation, as CSPP content increased, scores for color and consistency of crumb decreased, while scores for aroma of sweet pumpkin, sweetness, and delicious taste increased. Density of crumb pore were maximal with the 12% CSPP substitution. The CSPP samples had significantly higher uniformity of crumb pore and springiness of crumb than the control group. However, mouth-feel and overall acceptability showed the reverse effect, obtaining fairly good scores. In conclusion, the results indicate that substituting $6{\sim}9%$ CSPP to hard roll bread is optimal, providing good physiological properties as well as reasonably high overall acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1294-1300
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• 2008

Nelumbo nucifera G. tea white breads were prepared by the addition of 0.01, 0.02, 0.03, and 0.04% hemicellulase to flour of the basic formulation. The experiments and control were then compared in terms of quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, external and internal surface appearances, and sensory qualities in order to determine the optimal ratio of hemicellulase in the formulation. There were no significant differences in pH and total titratable acidity of dough among the experiments. Fermentation power of dough expansion were increased as incubation time increased. Baking loss was the highest at the 0.04% addition level, while the lowest at the 0.01% level. As hemicellulase content increased, pH, hardness, and fracturability of bread decreased, while total titratable acidity, specific volume, and resilience increased. Water content and lightness were the highest in the control bread samples, and yellowness was maximal in the 0.01% group. Bread made by the addition of hemicellulase had significantly higher greenness and flavor than the control group. Color, consistency, and springiness of crumb, density and uniformity of crumb pore, softness, chewiness, overall acceptability, lotus leaf flavor, delicious taste, astringency, bitterness, and off-flavor were not significantly different among the samples. The results indicate that adding 0.02$\sim$ 0.03% hemicellulase in N elumbo nucifera G. tea white bread is optimal for quality and provides a product with reasonably high overall acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.2042-2048
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• 2013

This research was carried out to compare the physicochemical characteristics of Korean traditional spirits brewed with Phellinus linteus by different Nuruks. The spirits were produced by atmospheric distillation of rice mash added with 1~5% P. linteus and fermented by traditional and improved Nuruks. Traditional Nuruk facilitated more alcohol production than improved Nuruk during the initial fermentation time. The alcohol contents of rice mash with P. linteus ranged from 15.8 to 18.9%. Predominant volatile compounds were i-amyl alcohol of fusel oils and ethyl acetate of ester compounds in P. linteus added spirits. The spirits prepared by traditional Nuruk showed higher contents of i-butanol, n-butanol, and i-amyl alcohol than those by improved Nuruk. More ethyl acetate was produced in the spirits prepared by improved Nuruk than those by traditional Nuruk. The contents of methyl alcohol were less than 50 mg/L in P. linteus added spirits.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.314-320
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• 2002

When the soybean milk residue flour were added to the respective wheat flour at level of 5%, 10% and 15% the possibility of bread making were studied. Vital gluten was added to the soybean milk residue portion of a 10% composite flour at levels of 3%, 6% and 9% to improve bread quality. And test was baking properties of soybean milk residue composite flour and sensory evaluation of composite breads. Major components of soybean milk residue flour were crude protein, 22.0%; crude lipid, 13.2%; carbohydrate, 54.3%; and dietary fiber, 27.2%. When 5%, 10% and 15% soybean milk residue flour was blended with wheat flour, water absorption, development time and bread weight were increased, and volume of dough and loaf was decreased. But improved bread-making properties by adding gluten. Color of crumb got darker as the percentage of soybean milk residue flour increased, got brighter when gluten was added. Texture of bread increased in chewiness and hardness as the percentage soybean milk residue flour increased but not different in cohesiveness. The use of vital gluten showed influence to springiness, chewiness and hardness. The sensory evaluation showed that 5% soybean milk residue-wheat bread was similar to bread made from wheat flour in overall acceptability. And the bread made by miting gluten were better than 10% soybean milk residue-wheat bread in overall acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1288-1293
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• 2012

Yacon (Smallanthus sonchifolius) contains high amounts of fructooligosaccharides and has been known to promote health of the intestinal tract and to have anti-oxidative and anti-cancer activities. Yacon concentrates were added to make five different pan breads, each with the addition 0% (YE 0), 25% (YE 25), 50% (YE 50), 75% (YE 75), and 100% (YE 100) of yacon concentrates instead of sugar. The higher the yacon concentration in the dough, the more time was needed for the dough to rise. Higher yacon concentration also affected the color of the bread by lowering the L-value and raising the a and b values. The hardness and chewiness of the bread significantly decreased with increasing yacon concentration, while cohesiveness increased. In the bread sensory evaluation, the intensity of crust color, crumb color, yacon flavor, sweetness, yacon taste, moistness, and residual mouth feel were increased with increasing yacon concentrates, while the uniformity of crumb pores slightly decreased. The consumer acceptance of taste, flavor, texture, and overall acceptance were increased with increasing yacon concentrations. As a conclusion, the substitution of yacon concentrates for sugar improved bread quality and increased consumer acceptance.

• The Korean Journal of Food And Nutrition
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• v.29 no.6
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• pp.930-937
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• 2016

This study investigated the quality characteristics, antioxidant activities, and retarding retrogradation of sponge cakes made with 0%, 1%, 3%, 5% and 7% pumpkin (Cucurbita moschata Duch.) leaf powder. Specific capacity significantly increased with the addition (0.33~0.38), but baking loss and dough yield were not significantly different (p<0.05). In color, there was a decrease in the L-value, a-value and b-value, but ${\Delta}E$ increased in proportion to the amount of pumpkin leaf powder. Moisture content increased in the 0~3% additions, from 27.90~31.68%, but decreased in 5% and 7% (22.37% and 28.15%, respectively). pH tended to decrease significantly according to the amount of pumpkin leaf powder (p<0.05). Hardness increased with the addition of pumpkin leaf powder, and pumpkin leaf groups presented higher springiness and cohesiveness than the control. Chewiness was not significantly differ (p<0.05). In retarding retrogradation, Avrami exponent (n) showed that addition of 5% (0.1329) had more retarding retrogradation effect than the control (0.4319), whereas time constant (1/k) showed both 3% (100.00) and 5% (70.42) addition had more effect than control (18.45). Total phenols and flavonoids content increased proportionate to the addition levels. ABTS radical scavenging activity tended to increase according to the level of pumpkin leaf powder. In sensory properties, 5% addition showed maximum color, and 3% addition had the highest scores in flavor, moistness, sweetness, chewiness and overall acceptability. These results suggested that pumpkin leaf was a good addition to improve the quality characteristics, health and sensory preferences. The most appropriate proportion to have the effect of retarding retrogradation in sponge cake is 3%.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.85-90
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• 2002

The changes in taste components of kanjang made with barley bran during fermentation time were examined. The pH was gradually decreased and total nitrogen content reached to 0.7% at 90 days fermentation. Five kinds of free sugars, three kinds of volatile organic acid, and eight kinds of non-volatile organic acid were detected. Lactic acid known as abundant component in kanjang was not detected in kanjang made with barley bran. The content of free amino acid was $422.9{\sim}803.6\;mg%$. Glutamic acid was most abundant component among the amino acids, followed by proline and phenylalanine. Essential amino acid content was revealed $34.3{\sim}37.3%$. Based on result of sensory evaluation, it was most comfortable to eat sample of fermentation $45{\sim}60$ days.

• Journal of the Korean Vacuum Society
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• v.18 no.5
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• pp.372-376
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• 2009

In the modern semiconductor industry, lithography process is used to construct specific patterns. However, due to the decreasing of line width, these days, more and more researchers are interested in PMMA(Poly Methyl Methacrylate) lithography by using e-beam instead of the prior method, PR(Photoresist) lithography by using UV(Ultra-Violet). Additionally, the patterns constructed by lithography are collapsed during the process of cleansing remnants and the resistance against the breakdown of the patterns is known to be proportional to the elastic modulus of pattern-constructing materials. In this research, we measured the change of hardness and elastic modulus of PMMA film surface according to the change of time spent to soft-bake the PMMA film. During the measurement, we controlled the tip pressure from $25{\mu}N$ to $8,500{\mu}N$ having intervals that are $134.52{\mu}N$. For these measurements, we used the Triboindenter from Hysitron to gauge the hardness and elastic modulus and the tip we used was Berkovich diamond Tip.