• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.907-914
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• 1996

To enhance the shelf-life and quality of baechu kimchi, the effects of CSP(crab shell powder) addition to kimchi was investigated. Overall qualities were deteriorated by fish odor, chewiness of particles, sharp pH increase at the early fermentation stage; therefore in order to solve these problems kimchi fermentation was carried out with kimchi containing 1, 3, 5% CSPB for salted baech weight at $10^{\circ}C$ for 300ays. Quality of kimchi was evalutated by the measurement of pH, acidity, colour L, a, and b value, the number of microbe and lactic acid bacteria, texture. Ten highly trained panelists were involved in the sensory evaluation. During the entire fermentation periods, pH, hardness, colour L, a and b value, the number of lactic acid bacteria of kimchi with CSPB were higher than those of control, but acidity was lower. Sensory quality showed that sour taste of control at 15-day fermentation was already strong. However, sour taste, crispness taste, and overall taste of kimchi with CSPB untill 20-day fermentation were good. Especially, overall taste of kimchi containing 3% CSPB at 30-day fermentation was good, but that of kimchi containing 5% showed fish odor from the early periods of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.434-441
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• 2015

To develop dough methods for improving bread making properties of Korean wheat flour, straight dough methods (SDM) and dough and sponge methods (DSM) were applied. The bread making properties such as weight of bread, specific volume, baking loss, crumb color, and texture were analyzed. In comparison of flour properties between Korean wheat flour and imported wheat flour by Farinograph, Korean wheat flour showed less gluten network form ability than imported wheat flour. The dough making method affected bread quality such as weight of bread, specific volume, and baking loss. SDM had a more desirable effect on bread quality. Crumb color was lighter in bread made with Korean wheat flour compared to imported wheat flour, whereas dough making method did not affect crumb color. In consumer acceptance analysis, bread made by DSM showed higher consumer acceptance than that made by SDM. Regarding physicochemical changes during storage, bread made by SDM using Korean wheat flour showed higher chewiness, brittleness, and hardness than that made by imported wheat flour. However, bread made by DSM showed similar chewiness as bread made by SDM using imported wheat flour. The bread making properties of bread made by DSM is improved versus that of bread made with Korean wheat flour.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.440-447
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• 2009

This study was performed to compare the wear resistance of sealant and flowable resins for analyzing the effect of flowable resin as a sealant in preventive resin restorations. Specimens were made and Vicker's hardness number and surface roughness were measured. SEM observations of the polished and abraded surfaces were established. Kruskal-Wallis rank test and Mann-Whitney U test at the significant level of ${\alpha}$=0.05 were used. The following results were obtained: 1. The microhardness was decreased among groups in following order: Z350 (3M ESPE, U.S.A), Estelite (Tokuyama Dental, Japan) and Ultraseal (Ultradent, U.S.A). There were significant differences in all groups (p<0.0001). 2. The surface roughness was decreased among groups in following order: Ultraseal XT plus, Palfique Estelite LV and Filtek Z350 flowable. However, there is no statistically significant differences in roughness among Estellite, Z350 and Ultraseal at the significance level of ${\alpha}$=0.05, with p=0.116 3. SEM observation of the unworn and worn surfaces revealed the qualitative differences in the wear appearance among groups. The results in this study indicate that flowable resin is better than sealant in aspect of physical properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1103-1108
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• 2013

This study was conducted in order to determine the effect of autoclave and microwave treatments on cookies. Wheat dough was treated in an autoclave (30 min), a microwave (1 min), and both autoclave and microwave (30 min/1 min). The treated dough was baked or non-baked and cookies quality was assessed. The pH, moisture content, color, and texture were measured, and sensory evaluation was performed. The pH showed a slight increase when dough was treated in a microwave (before baking) and decreased in both the autoclave and autoclave/microwave (after baking) treatments. The moisture content showed a significant increase, compared to the control, in autoclave treatments. Regarding surface color of cookies, lightness was decreased in all treatments and redness was higher compared with the control, except for microwave (before baking), and yellowness was lower compared to the control, except for microwave treatment (after baking). Hardness, gumminess, chewiness, and shear force showed a significant increase when dough was treated in an autoclave/microwave (after baking) compared to the control. In the sensory evaluation, color, taste, texture, shape, and overall preference of cookies treated with an autoclave/microwave (after baking) showed a low score. These results suggest that autoclaving and microwaving may reduce the quality of bread and that preparation of countermeasures is necessary.

• The Korean Journal of Food And Nutrition
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• v.22 no.3
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• pp.321-331
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• 2009

In this study, Salvia miltiorrhiza Bunge(Danshen) powder was extracted with ethanol, and its antimicrobial activity was investigated. The ethanol extract of the Danshen had antimicrobial activity against Bacillus subtilis, Escherichia coli, and Staphylococcus aureus. The inhibition zones of the Danshen extract(3 mg/disc) against B. subtilis, E. coli and S. aureus were 13, 12 and 8.5 mm, respectively. To test the food preservation effect of Danshen and determine the optimal ratio of the Danshen extract in a formulation, Sulgidduk samples were prepared with substitutions of 0, 0.25, 0.5, 0.75 and 1% Danshen extract, and then their quality characteristics were investigated over 4 days of storage. According to the results, total cell counts showed a decreasing trend with an increasing amount of added Danshen extract. Moisture contents were not significantly different among the Sulgidduk samples. As the content of Danshen extract increased, the L-values of samples decreased and the a- and b- values increased. For the textural characteristics, the hardness, gumminess, and chewiness of the Sulgidduk samples decreased as the amount of Danshen extract increased; however, they increased with the progression of storage time. In the sensory evaluation, the control group had significantly higher scores for color, flavor and after-taste as compared to the Danshen extract-added groups. With increasing Danshen extract contents, flavor and overall acceptability decreased, while Danshen flavor, bitterness and off-flavor increased. Chewiness was not significantly different among the samples. In conclusion, the results indicate that substituting 0.5% Danshen extract in Sulgidduk is optimal for quality and provides a product with reasonably high overall acceptability.

• Korean journal of food and cookery science
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• v.9 no.3
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• pp.198-203
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• 1993

The objective of this study was to evaluate the effect the Seokibyung, when the ingrdients were changed in a variety aspects ; the amount of Seoki flour to rice flour, and several kinds of sweeteners such as sugar, honey and syrup and condition of water. The evaluation of these result were as followings ; 1. According to sensory evaluation, the, flavor, grain, softness, moistness, chewiness, sweetness, overalquality of Seokibyung were the most excellent the mixture of 60g sugar, 280g rice flour, 70g glutious rice flour and 10.5g seoki flour mixed in 90$m\ell$ boiled water. 2. According to Instron evaluation that the higer level resulted to the left to the right treatment that Hardness : syrup, honey, sugar Cohesiveness : honey, syrup, sugar, Adhesiveness : syrup, honey, sugar Gumminess : honey, syrup, sugar Springness : honey, sugar, syrup, Chewiness : honey, syrup, sugar. there was no significant difference among the three treatment groups in each experimental group. 3. The Color & color difference evaluation_that Overall color difference was sugar, honey, syrup in turn. 4. percentages of moisture of honey-added, sugar-added and syrup-added Seokibyung were 42.49%, 41.45% and 36.73% respectively.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.603-609
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• 1992

To investigate the effect of polyethylene film packaging and $CO_2$ treatment on tomatoes during storage, the gas composition in film, weight loss, the changes of color, hardness and several components were measured. The concentrations of $CO_2$ and $O_2$ in film were changed rapidly in early stage, but it kept a constant level after 7 days of storage. In 0.06 mm polyethylene film, $CO_2$ and $O_2$ concentration was kept a level of $4{\sim}6%$ respectively. The increase in $C_2H_2$ concentration was delayed in thick and $CO_2$ treated film. The rate of weight loss was 4% in non-packed tomatoes, but it recorded about 1% in 0.06 mm polyethylene film. Titratable acidity, pH and soluble solids were changed slightly, but the obvious differents were not observed according to film thickness and $CO_2$ treatment. The value of tomatoes was increased but L and b values were not changed greatly during storage. These color changes were restricted by 0.06 mm film and $CO_2$ treatment. The firmness and content of ascorbic acid were reduced during storage but it restrained by $CO_2$ treatment and film packaging. Sugar of tomatoes were composed of glucose, fructose and a very small amount of sucrose, and they were changed little during storage.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.3
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• pp.19-27
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• 2003

Surface finishes of PCB laminates are important in the solder joint reliability of flip chip package because the types and thicknesses of intermetallic compound(IMC), and compositions and hardness of solders are affected by them. In this study, effects of surface finishes of PCB on the low cycle fatigue resistance of Sn-based lead-free solders; Sn-3.5Ag, Sn-3.5Ag-XCu(X=0.75, 1.5), Sn-3.5Ag-XBi(X=2.5, 7.5) and Sn-0.7Cu were investigated for the Cu and Au/Ni surface finish treatments. Displacement controlled room temperature lap shear fatigue tests showed that fatigue resistance of Sn-3.5Ag-XCu(X=0.75, 1.5), Sn-3.5Ag and Sn-0.7Cu alloys were more or less the same each other but much better than that of Bi containing alloys regardless of the surface finish layer used. In general, solder joints on the Au/Ni finish showed better fatigue resistance than those on the Cu finish. Cross-sectional fractography revealed microcracks nucleation inside of the interfacial IMC near the solder mask edge, more frequently on the Cu than the Au/Ni surface finish. Macro cracks followed the solder/IMC interface in the Bi containing alloys, while they propagated in the solder matrix in other alloys. It was ascribed to the Bi segregation at the solder/IMC interface and the solid solution hardening effect of Bi in the $\beta-Sn$ matrix.

• Journal of dental hygiene science
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• v.13 no.1
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• pp.13-19
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• 2013

This study evaluated the change of color and the microhardness according to time-out using the office bleaching with in vitro test after bleaching one time 1 day per week, total three times, for the control group and three times per 1day for the experimental group. $L^*$ was increased in both groups. Group 1 showed a significant increase statistically between before and after tooth whitening (p<0.05). Group 2 showed a significant increase statistically between before and after tooth whitening (p<0.05). ${\Delta}E^*$ was huge in both groups. In group 1, it was great in terms of statistical significance between 1 day and 7 days after tooth whitening (p<0.05). In group 2, it was the greatest between before and 1 day after tooth whitening and was significant statistically as well (p<0.05). Vickers hardness number (VHN) decreased in both groups. In group 1, VHN decreased over time and the difference was significant statistically (p<0.05). In group 2, VHN decreased over time and the difference was significant statistically (p<0.05). Percentage microhardness loss was great in both groups. In group 1, it was the greatest between 1 day and 7 days after the treatment, and it was significant statistically (p<0.05). In group 2, it was the greatest between before and 1 day after the treatment, and it was significant statistically (p<0.05). Put together, the more frequent tooth whitening a day is, the longer the period of tooth whitening when applying the same frequency, the greater color change was, however the microhardness decreased, in regard to the results over time using 15% hydrogen peroxide tooth whitening product for professionals.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.684-696
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• 1995

A mutant for chalky endosperm and genetic male sterility (GMS) was newly developed in rice. The two characters were found to be controlled by single recessive gene which has pleiotropic effect, indicating that chalky seeds should be GMS seeds in segregating populations. Chalky seeds showed the same shape and size as normal seeds. However, starch composition of central part of endosperm was looser and shape of starch granules was rounder compared with normal endosperm, resulting in significantly lower grain weight, absolute density and grain hardness in chalky grains than in normal ones. Amylose content and gel consistency of chalky grains were much lower and harder, respectively. Male sterile plants showed much shorter plant height, poorer panicle exsertion and lesser panicle number compared with normal plants. Microspore abortion stage in pollen developmental process was observed as before meiosis. Male sterility of the mutant was stable regadless of temperature and day length. A system breeding hybrid rice using this mutant was discussed, comp ring with other systems utilizing cytoplasmic-genic male sterility(CGMS) and environment sensitive GMS(EGMS). Separation of GMS seeds in mixed seed bulks by specific gravity (1.14∼1.16g / cm3) was successful about 85∼90%. But some mixed normal plants were seemed to be easily removed by the apparent difference in growth characters at seedling stage. The highest natural outcrossing rate of this GMS line was as 17.3 % in a plot treated with 2-row pollinator, I-row GMS, and GA3 + cutting of flag leaf + pollen-scattering by rope.