• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.525-531
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• 2018

This paper proposes a bi-component dye, including the unripe fruit of Diospyros kaki THUNB and Ecklonia cava, to substitute for traditional persimmon dyeing because fabrics dyed with persimmon juice become stiffer and natural persimmon is insufficient for dyeing. This study examined the color difference and fabric stiffness depending on the ratio of Ecklonia cava for in a one-bath dye solution with Diospyros kaki THUNB and showed that 6% of Ecklonia cava in the bi-component dye was the optimum for decreasing the fabric stiffness. Based on these results, a bi-component dye constituting of 94% Diospyros kaki THUNB and 6% Ecklonia cava was prepared. The particle size was found to be smaller than both single dyes and it maintained a similar amount of Catechin to Diospyros kaki THUNB dye. Finally, cotton fabric dyed with a bi-component dye was much improved in terms of the fabric hand and the surface color was similar to that of the traditional persimmon-dyed fabric. These results could help to develop the natural persimmon dyeing industry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.450-458
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• 2017

In this study, the antimicrobial activity of black garlic pomace extract (BGPE) was examined, and its washing applicability to spinach was investigated. BGPE had antimicrobial activity against both Gram-positive (Listeria monocytogenes and Staphylococcus aureus) and Gram-negative (Escherichia coli O157:H7 and Salmonella Typhimurium) food-borne pathogens. In particular, antimicrobial activities of BGPE against Gram-positive bacteria were higher than those against Gram-negative bacteria. Spinach samples were treated with 0.5% BGPE to determine the effect of BGPE on reducing naturally existing microorganisms on the surface of spinach leaves. BGPE treatment reduced populations of total aerobic bacteria and yeast/molds in spinach by 1.23~1.35 log CFU/g and 0.82~1.12 log CFU/g during 9 days of storage, respectively, compared with those of control samples. After treatment, there were no significant differences in color quality such as Hunter L, a, and b values and total color difference (${\Delta}E$). These results clearly indicate that BGPE treatment can be useful for improving microbiological safety and maintaining color quality of spinach during storage.

• Journal of Conservation Science
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• v.36 no.6
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• pp.549-561
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• 2020

This study aimed to assess the performance and life of nine natural mineral dancheong pigments: Seokganju, Jinsa, Hwangto, Jahwang, Wunghwang, Seokrok, Noerok, Seokcheong, and Baekto. The design of the accelerated weathering test considered the domestic climate characteristics and the location of Dancheong. Outdoor weathering tests were conducted at the Research Institute in Daejeon and the Sungnyemun Gate in Seoul to confirm the field reproducibility of the accelerated weathering test. Monitoring of the physical changes in pigments through accelerated and outdoor weathering tests are based on ultraviolet exposure dose. Despite small cracks at the beginning of the tests, the monitoring showed that Seokganju and Baekto had no marked physical changes, but the surface cracks of Jinsa and Seorok continue to expand. Hwangto and Noerok were marked with water or were resin stained, and the particles of Jahwang, Wunghwang, and Seokcheong had lost their luster. Despite the absolute difference in color change in each test, the final chromaticity change patterns of pigments were similar in that the color difference between Baekto and Noerok was below five, and Jina was above 28. The physical and surface color pigment changes were more concentrated in outdoor weathering tests than in accelerated tests, and the Seoul site was more intense than the Daejeon site. This is because outdoor weathering tests are exposed to severe variations of temperature and moisture or deposition of dust particles and, in the case of Seoul, the site is more exposed to the external environment than the Daejeon site.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.33-38
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• 2010

This study was conducted to compare the physicochemical properties of powdered green teas produced in Korea and Japan including particle size, color, chlorophyll, caffeine and theanine. The average particle size of Korean powered green tea ($14.63-25.39\;{\mu}m$) was similar to that of Japanese powdered green tea ($15.46-21.02\;{\mu}m$). The surface color of shade-cultivated Haenam Green Tea (HN-1) had the highest negative 'a' value, which represents 'green' color. When the TCD (total color difference value) was measured in the samples, HN-1 was most similar to the premium powdered green tea of Japan (JA-1). Domestic shade-cultivated powdered green teas had 1.5-2 times greater chlorophyll content than powdered green teas produced from plants that were not cultivated in the shade. The presence of chlorophyll a resulted in a higher intensity of green color than the presence of chlorophyll b. A significant negative correlation was also observed between the color and the chlorophyll a, chlorophyll b and total chlorophyll contents. Specifically, chlorophyll a had the greatest impact on the green color of powdered green tea. The content of catechins, caffeine and theanine in Korean powdered green teas ranged from 14.679-20.128, 1.496-3.237 and 0.926-1.977 g/100 g, respectively. The caffeine and theanine contents were high in shade-cultivated powdered green teas. Based on the above results, domestic powdered green teas cultivated under shaded conditions had a quality similar to that of medium-quality green teas produced in Japan, and the overall quality of Korean powdered green tea was poorer than that of Japanese powdered green tea.

• Economic and Environmental Geology
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• v.53 no.2
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• pp.197-212
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• 2020

This study was carried out material characteristics and firing conditions for some potteries in early and middle Neolithic period at the Munamri sites, where the first farmland remails were found in Korea. It is divided into six kinds of surface patterns for potteries such as the raised, bamboo tube and red painted (patternless) from the early Neolithic period (BC 4000 to 6000), and the patterns of horizontal herringbone, short slanted lined or lattice and incised thick line in the middle Neolithic period (BC 3000 to 4000), respectively. Based on the color measures, redness and yellowness of potteries were relatively high as condition of oxidation firings, were also observed black cores on the cross section of potteries. The firing temperature is divided into two groups having under 800℃ and 800to 900℃, the difference in patterns of the potteries are not confirmed. As a microtextures, the bamboo tube pattern potteries show the sericitization biotite, the quartz have developed a suture line textures, and altered alkali feldspars are occurred. X-ray diffraction analysis shows that the main minerals contained in potteries are chlorite and amphibole besides quartz, alkali feldspar and biotite. Considering the geology around the Munamri area is the biotite amphibole granite and soil layers within 10km radius are used as the raw materials for the potteries. The raw materials are presumed that the sources from the metamorphic rocks along the water systems through the mountains around the sites on the basis of well developed suture line textured quartz in potteries. Results on normalized geochemical compositions, the potteries by surface patterns are very similar to sources, and it is judged that was made by using the surrounding soils despite the long time difference from the early to middle in the Neolithic period.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.32-38
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• 2003

The effects of curing temperatures(1, 5 and 10$^{\circ}C$) and times on the chemical properties and palatability of cured pork loins which were cured in the 7% curing solution were investigated. The pork loins cured at 10$^{\circ}C$ curing temperature showed the decreased level of pH and water holding capacity up to 15 days of curing time. The growth of bacteria in the curing solution and surface region of cured loins, cured at 10$^{\circ}C$ were rapid after 12 days of curing. However, bacteria were not detected(<0.05${\times}$10$^2$ CFU/g) in the central region of cured loin until 15 days of curing. The penetration of salt into the central region of cured loins was faster at 10$^{\circ}C$ curing temperature than at lower curing temperatures for all curing times. The difference of salt contents between surface and central regions in the cured loins was less at higher temperature than at lower temperatures, and the difference decreased in boiling process for all curing times. The color fixation of the cured boiled loins was better at 5 and 10$^{\circ}C$ curing temperatures than at 1$^{\circ}C$. The sensory scores for saltiness and flavor of the cured boiled pork loins were higher at higher temperature than at lower temperatures until 9∼12 days of curing. Palatable cured boiled pork loins could be produced under the curing solution at low temperatures of 1 and 5$^{\circ}C$ for 12 and 9 days, respectively.

• Journal of dental hygiene science
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• v.8 no.4
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• pp.255-260
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• 2008

The purposes of this study were to examine the effect of 35% hydrogen peroxide (HP) bleaching agent on the changes in physical and chemical characteristics of tooth. The bleached teeth showed an apparent color changes. The whiteness increased linearly within the tested period as the period of bleaching increased. The microhardness between bleached groups after bleaching showed any statistically significant difference according to the paried t-test. The bleached enamel surface showed any apparent morphological changes compared to the enamel which was stored in distilled water only. The difference of the total mineral contents for the distilled water and hydrogen peroxide did not show statistical significance. These results demonstrated that bleaching using 35% hydrogen peroxide were adversely affects application time of experimental group and may confirm the safety of using these agents for a short time in dentist-monitored bleaching.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.593-600
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• 2021

In this study, the vacuum distillation process for producing non-alcoholic red wine was optimized via response surface methodology. As a result of optimizing the responses (alcohol content, yield) for independent variables (operating time, boiling point, and temperature difference), 1% alcohol content and 81.15% yield were obtained at an operating time of 24.5 min, boiling point of 65℃, and temperature difference of 8℃. To investigate the physicochemical and sensory properties, non-alcoholic wines with different boiling points (bp 25℃, bp 45℃, and bp 65℃) and a blended wine (4.2% of control wine added) were prepared. As the boiling point increased, the alcohol content decreased, and CI (color intensity) and Hue increased. Blended wine exhibited the highest value and bp 65℃ showed the lowest value in terms of sensory properties. In conclusion, distillation at a low boiling point and blending control wine could be used to prepare non-alcoholic wine with a high preference.

• The Journal of Engineering Geology
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• v.9 no.2
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• pp.161-176
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• 1999

The objectives of this study are to analyze the changes of geo-surface topography in the Siwha embankment and the Ahsan city area by the image processing of Landsat Thematic Mapper data, and to estimate the reclaimed amount of the exposed tidal flat in the Siwha area using the GIS. False color composite, Tasseled cap, NVDI(normalized difference vegetation index), and supervised classification techniques were used to analyze the distribution of sediments and the aspect of topographical variations caused by artificial human actions. The total amount of the exposed tidal flat was estimated on the basis of the database snch as aerial photography, hydrographic chart, geological map, and scheme drawing in the Siwha area. The possible excavation regions for a seawall were predicted analyzing the supervised classification image of Landsat TM data. Tasseled cap images were used to observe the distribution of sediments. The difference of the NDVI images between spring and summer seasons indicates that deciduous and coniferous forests were distributed over the whole areas. The total fill-volume of the exposed Siwha tidal flat and the fill-volume of the construction planning seawall were calculated as $581,485,354\textrm{m}^3{\;}and{\;}3,387,360\textrm{m}^3$, respectively, from the digital terrain analysis. Daebu Island, Sunkam Island, and the part of Songsan-myeon were chosen as the cut area to make the seawall, and their cut-volumes were estimated as $5,229,576\textrm{m}^3,{\;}79,227,072\textrm{m}^3,{\;}and{\;}47,026,008\textrm{m}^3$, respectively. Therefore, the cut-volume of Daebu Island alone among three areas was sufficient to make the seawall.

• Journal of Bio-Environment Control
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• v.19 no.2
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• pp.88-92
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• 2010

This study was conducted to compare the quality characters of 15 different tomato cultivars ('Dotearang Dia', 'Super Dotearang', 'Super sunroad', 'Hoyong', 'Mirokku', 'Baccuhs', 'Mascara', 'Poseidon', 'Radido', 'Madison', 'Rapsodie', 'Solomon', 'Amaral', 'Picasso', 'Tymaxx') and find out the correlation among the quality characters in order to get basic informations for exporting tomato. The $a^*/b^*$ value of fruit surface showed from 2.8 to 4.8, but there was no significant difference in fruit surface color value, such as $a^*$, $b^*$ and $a^*/b^*$ among the cultivars. The respiration and ethylene production rate also were not shown any significantly difference among cultivars. The firmness of fruit was higher in 'Picasso', 'Tymaxx' and 'Madison' cultivars. The contents of soluble solids was higher in 'Hoyong' and 'Dotearang Dia' cultivars. The vitamin C content was higher in 'Super Sunroad' and 'Dotearang Dia' cultivars. The titratable acidity was higher in 'Hoyong' cultivars. The sugar/acid ratio that depended on soluble contents was lower in 'Amaral', 'Picasso', 'Tymaxx' cultivars that showed lower soluble contents. Conclusionally, The firmness that was one of the most important quality character in exporting tomato was higher in European cultivars, but soluble solide and vitamin C content were higher in Japanese cultivars. The significant correlation coefficient values were determined (more than p = 0.05) between $a^*/b^*$ and other quality characters. The results suggested that surface color was the most suitable character represented tomato qualities. The high coefficient value (r = 0801) between $a^*/b^*$ and the contents of soluble solids. The firmness and the contents of soluble solids that is the most important factor for exporting showed significant negative correlation (r = -0.611).