• Horticultural Science & Technology
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• v.32 no.5
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• pp.645-654
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• 2014

This study was conducted to investigate the effect of 1-methylcyclopropene (1-MCP, $1.0{\mu}L{\cdot}L^{-1}$), a known ethylene action inhibitor, on fruit quality and incidence of physiological disorders during a simulated marketing period at $25^{\circ}C$ for 20 days in early-season Asian pear (Pyrus pyrifolia Nakai) 'Hanareum' that had been treated with 0, 0.5, 1.2 or 2.4% $GA_{4+7}$. Weight loss of stored fruits increased with $GA_{4+7}$ concentration, and the 1-MCP treatment slightly reduced the weight loss rates during the marketing period. Flesh firmness decreased abruptly in all 1-MCP-untreated fruits as the storage period extended to 10 d, whereas the firmness of 1-MCP-treated fruits remained high (> 30 N) during 15 days shelf-life. The effect of 1-MCP was significantly reduced when fruits were subjected to increased GA concentration. Higher soluble solids content and acidity during extended shelf-life were also apparent in 1-MCP-treated 'Hanareum' pears. The L-values (lightness) and hue angles of 1-MCP treated samples were higher than those of controls during 20 days shelf-life, but the a-value (redness) was lower in 1-MCP treated fruits. 1-MCP treatment did not decrease the level of ethylene evolution regardless of $GA_{4+7}$ concentration during shelf-life in early-season Asian pear 'Hanareum'. By contrast, 1-MCP treatment decreased the respiration rate significantly during shelf-life. The efficacy of 1-MCP was greatest in the GA-untreated fruit and was reduced as the $GA_{4+7}$ concentration increased. 1-MCP treatment influenced the severity of physiological disorders including core browning and mealiness: 1-MCP treatment completely blocked the incidence of core browning of during 15 days shelf-life, and reduced the severity of mealiness during 20 days shelf-life regardless of $GA_{4+7}$ concentration. Based on our results, we conclude that the use of $1{\mu}L{\cdot}L^{-1}$ 1-MCP can be of great benefit for maintaining quality and preventing physiological disorders in early-season pear cultivar 'Hanareum' pear, whereas its efficacy decreases with the concentration of $GA_{4+7}$ whereas its efficacy gradually decreases when the concentration of $GA_{4+7}$ paste increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.744-751
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• 2008

Physicochemical properties of Gugija-sugar leaching were investigated by adding sugar ratio on Gugija (Lycii fructus) raw fruit. Gugija were prepared by parboiling ($40{\sim}50$ sec at $85^{\circ}C$) and unparboiling. Gugija-sugar leaching were leached after preserving (5 months at $5^{\circ}C$) Gugija-sugar mixture (20, 40, 60, 80 and 100% sugar based on raw Gugija). The yield increased with UPRGSL-4 (Gugija-sugar leaching adding 80% sugar) having the highest yield at 77.5%; in contrast, total acidity decreased with increasing ratio of sugar. The main organic acids of raw Gugija are tartaric acid (0.63%), citric acid (0.57%), malic acid (0.54%) and succinic acid (0.3%). Citric acid and succinic acid decreased with increasing ratio of sugar but malic acid and tartaric acid increased on Gugija-sugar leaching. Polyphenolics and betaine content of unparboiling Gugija-sugar leaching decreased as increase ratio of sugar but in term of used Gugija amount, betaine content of each Gugija-sugar leaching was equal to raw Gugija. Also, parboiling Gugija-sugar leaching decreased quickly with increasing ratio of sugar, especially PRGSL-4 and PRGSL-5 (parboiling Gugija-80 and 100% sugar leaching, respectively) was not determined. 15 types of free amino acids were detected in raw Gugija; the total content was 601.6 mg/100 g and the highest amino acid among them was serine, 218.1 mg/100 g. In PRGSL-4 prepared by parboiling, 9 kinds of free amino acid were detected and the total content was 383.3 mg/100g. Also, in UPRGSL-4 (unparboiling Gugija-80% sugar leaching), all 17 kinds were detected and its total content was 705.7 mg/100 g.

• Food Science and Preservation
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• v.8 no.4
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• pp.419-426
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• 2001

This study was carried out to develope a convenient instant spiced Toha-jeot. Toha-jeot was manufactured by five samples; 8%, 10%, 13% 23% sodium chloride and a conventional type soy sauce. The Toha-jeot was refrigerated at 4$\pm$1$\^{C}$ for 3 months and then boiled glutinous rice, red pepper powder, chopped garlic and ginger were added, and the spiced Toha-jeot was fermented at 4$\pm$1$\^{C}$ for 2 months, was freeze-dried at a condition of 40$\^{C}$, vacuum 100∼200 millitor millitorr and then packed in vacuum. It is called freeze-dried instant spiced Toha-jeot (FIST). Changes in the components and quality of refrigerated spiced Toha-jeot (RST) and FIST were investigated for 30day. The moisture content of RST was 53.79∼58.91%. Among the mineral constituents of RST, Na and Ca were dominantly occupying. Water activity of FIST was 0.28-0.39 while that of RST was 0.87-0.92. TBA value of FIST was lower than that of RST. Acidity, VBN (volatile basic nitrogen) and TBA(thiobarbituric acid) of the FIST and RST increased slightly, whereas pH decreased. The major components of fatty acids in FIST and RST were analysed into a feater amount of linoleic acid (Cl8:2), palmitic acid (Cl6:1), oleic acid (Cl8:1), linolenic acid (Cl8:3), EPA (C2O:5) and stearic acid(Cl8:0). In sensory evaluation, the RST had higher scores in color and taste and the FIST in chewiness and flavor. The qualitative characteristics and sensory evaluation of FIST and RST were similar.

• Food Science and Preservation
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• v.18 no.5
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• pp.661-668
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• 2011

This study was conducted to devise appropriate blanching-process conditions as a means to convert Doraji, which is widely used in Korean food due to its unique fragrance and flavor, into frozen food materials for various uses. For the Hunter L values representing the brightness transformation among the surface color and gloss changes that were observed in Doraji before and after freezing, and after Doraji went through a blanching process, the specimen that went through a blanching process at $80^{\circ}C$ showed a significantly higher value compared to another specimen processed at a higher temperature, and the first specimen's value also rose after freezing. Meanwhile, for the hardness values, they declined more as the blanching temperature became higher and as the processing time became longer. For the number of total counts and the number of coliform groups, the number of total counts at $3.75{\times}10^5$ and $1.25{\times}10^5$ cfu/g before the blanching process was reduced into the approximately 2-3 log scale, and no coliform group was detected after the blanching process. As for the peroxidase activity, its activation was decreased by the blanching process, and more than 89% of the peroxidase became inactivated in all the specimens that went through the blanching process. The sensory characteristics of the frozen-thawed Doraji by test group showed the radish leaves blanched at $90^{\circ}C$ for 1 min to be the most highly evaluated in terms of the overall preference level (p<0.05).

• Food Science and Preservation
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• v.21 no.1
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• pp.129-139
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• 2014

This study was conducted in order to investigate the optimal fermentation periods of the Smilax china L. leaves as a fermented tea via Aspergillus oryzae for 0 (non-fermented), and 10, 20, and 30 days (NF, F10, F20, F30). It was also observed for its quality characteristics. In the color and spectrum (400~700nm) of 1% tea water extract, NF was light yellow, whereas fermented tea (F10~F30) was light red color, and the F10 among F10~F30 has the clearest color and spectrum. Furthermore, acceptabilities of aroma and brightness were insignificantly different between NF and F10~30, while the mouth feel and overall acceptabilities were insignificantly distinct among all of the fermented teas. Therefore, these results suggest that the appropriate fermentation period for tea fermentation is 10 days. On the other hand, the total polyphenol and flavonoid content in the NF was the highest among all of the fermented teas. In the antioxidant parameters, EDA (electron donating ability), FRAP (ferric reducing antioxidant power), and LPOIA (lipid peroxidation inhibitory activity) in the NF were the highest among all fermented teas. Meanwhile, the XOI (xanthine oxidase inhibitory activity) was low, as well as insignificantly different from NF and F10~F30, whereas the AOI (aldehyde oxidase inhibitory activity) was markedly higher (38.09~41.70%) by the hot water tea extract (with or without fermentation), particularly the AOI that has increased via fermentation. In conclusion, the overall antioxidant activity tended to be reduced by fermentation; however, the EDA, FRAP and LPOIA in the fermented tea for 10 days was higher than the activities during 20~30 days of fermentation. There was a similar result in the color and acceptability of fermented tea for 10 days, which was remarkably better than those of 20-30 days. Therefore, fermented tea from the leaves of Smilax china L. could be expected to be used as a functional tea without the loss of inhibitory activity of both the XO and AO via fermentation.

• Food Science and Preservation
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• v.20 no.5
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• pp.659-667
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• 2013

This study was performed to determine the effects of the blanching condition (immersion ratio 1:15 (w/v) for 3 min at $95^{\circ}C$, and solution containing 1% sodium chloride) and selected forming agents (dextrin DE=10, dextrin DE=20, ${\beta}$-cyclodextrin; each forming agents added 5%) on the phytochemical compounds and quality characteristics of Ligularia fischeri leaves. The moisture was not affected by the forming agent. The color of a, b and chroma values were low in the blanching treatment groups and were significantly lowest with ${\beta}$-cyclodextrin (CD). The polyphenol and flavonoid contents in the blanching treatment groups were higher than those in the non-blanching-treatment group. The ascorbic acid content was higher in the non-blanching-treatment group and was significantly highest in the group treated with dextrin (DE=10) whereas the blanching treatment groups showed lower dehydroascorbic acid content than the non-blanching-treatment group. The water absorption was higher in the non-blanching-treatment group and was significantly highest in the group treated with CD. The water solubility in the blanching treatment groups treated with dextrin (DE=20) and CD was higher than that in the blanching treatment group treated with DE=10. The total chlorophyll and chlorophyll a and b contents were high in the blanching treatment group treated with CD, and for the total carotenoid contents, the same tendency as that seen with the chlorophyll content was observed. With regard to the particle diameter, those in the blanching treatment groups were lower than that in the non-blanching-treatment group and was significantly lowest in the blanching treatment groups treated with DE=20 and CD. The result of SEM observation showed that the spray-dried powders in blanching treatment groups treated with the DE=20 and CD forming agents had uniform particle distribution.

• Journal of dental hygiene science
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• v.15 no.3
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• pp.265-271
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• 2015

This study has an objective not only to be helpful to the understanding about students' career and employment preparation by investigating the present conditions which are related with vocational consciousness and job values of dental hygiene department graduating students. Study subjects were 350 female graduating students in 3-year-course College, dental hygiene department at five areas of Seoul, Gyeonggi, Gangwon and Gyeongnam. Data were analyzed using IBM SPSS Statistics ver. 19.0. Regarding job values, job prospect of dental hygienist is a little developmental (55.2%) and institution hoping to work is dental clinic (43.2%), reasons for employment in major area are good wage and working environment (24.0%). And regarding opinion about job, dental hygienist job is a measure for living income (69.7%). Regarding job selection conditions, 35.0% subjects replied good human relationship. In the questionnaires regarding professional job in vocational consciousness category, results showed high percentages in that 'the occupation is a job in charge of oral health improvement'; regarding academic area, 'scaling should be done better than dentist'; regarding human relationship, 'harmony between colleagues is closely related with job efficiency'; regarding work ethics, 'development of dental hospital (clinic) and dental hygienist is correlated.' In vocational consciousness of study subjects, higher major satisfaction showed significant differences in professional job consciousness and work ethics consciousness (p<0.05) and the correlation results in vocational consciousness areas showed all statistically significant correlations (p<0.01). In case that the characteristic in one type is higher among 4 types, all other types showed high characteristics and also showed high general vocational consciousness.

• Korean Journal of Heritage: History & Science
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• v.52 no.4
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• pp.206-225
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• 2019

This paper examines the trade and development aspects of glass mirrors through the literature records of the Joseon Dynasty, and studies the characteristics of existing glass mirror crafts by referring to the terms and types shown in the literature. The glass mirror in the records had called western mirrors(西洋鏡, 洋鏡), glass mirrors(玻璃鏡, 玻瓈鏡), stone mirrors(石鏡), etc. Glass mirrors were imported mainly through trade with Russia and the Qing Dynasty since the 17th century and were banned from importation in the late Joseon Dynasty. These mirrors were something new that caused a great stirring in Joseon society in the 18th century, and in the 19th century, it grew larger as a commodity needed for everyday life, especially with trade with Japan. At that time, glass mirrors were used for various purposes, such as installing large glass at a store, which were not the standard mirror usage of confirming one's appearance. These mirrors surprised Koreans in Joseon who experienced them at Yanjing Liulichang(燕京 琉璃廠) in the 18th and 19th centuries. As a result, the demand for glass mirrors rapidly increased and quickly surpassed that of bronze mirrors. Consequentially, new crafts using glass mirrors instead of bronze mirrors in Joseon began to be produced and used after the 18th century. In particular, integrated flat boards of glass mirrors were developed as crafts used indoors. It was convenient to use the hair comb box, a long-time presence in Joseon society, with the bronze mirror. This kind of mirror remained apparent in various genre paintings, including the Taepyeong Seongsido(太平城市圖, 'A Thriving City in a Peaceful Era') collected the National Museum of Korea which reflect its populism of the times. Also, the Mirror Stand(鏡臺) used in the Qing Period was produced in Joseon, but there was a difference in the way of making the drawers and box shapes between two nations. On the other hand, the Face Mirror(面鏡) was made to look at the face. Various crafts made with the aesthetic sense of Joseon, such as the ox horn inlaying craft technique, were produced with auspicious designs. In the 19th century, glass mirrors were imported from European countries, such as France, Denmark, the Netherlands, and the United Kingdom, however after the end of the 19th century Japanese crafts were popular. Glass mirrors, which were popular in the Meiji and Taisho eras of Japan, were imported and also the Mirror Screen(鏡屛) using large glass mirrors were used. In particular, the mirror screen had developed wood furniture since the previous time, which were used for banquets and large spaces, such as the drawing room, and were imported from China and Japan. In addition, the western architectural effect of attaching a mirror to the wall was also attempted to adjust the brightness of the space and introduce another image and scenery in the mirror. This was done at Deoksugung Palace's Seokjojeon.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.4
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• pp.533-538
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• 2014

Purpose: This study is to investigate correlation between eye fatigue and letter contrast according to letter contrast changes on monitor display. Methods: Reading speed test were carried out for 53 subjects (mean age: $22.68{\pm}1.85$ years) who have over Best-corrected visual acuity (BCVA) 1.0, and 45 subjects, who could read over 123 out of 163 letters among 53 subjects were selected. They were asked to read the letters which were composed of Black (contrast 100%), Dark gray (contrast 80%), Gray (contrast 80%), Light gray (contrast 30%) randomly. The change of their eye fatigue by letter contrast on monitor display was measured by monitoring their eyes with an eye-tracker while they were reading letters. Results: Event Duration (sec) was 33.635 for Black, 32.266 Dark gray, 33.936 for Gray, and 34.848 for Light gray. Average of Fixation Duration (sec) was 0.224 for Black, 0.218 for Dark gray, 0.239 for Gray and 0.243 for Light gray. Average of Pupil diameter (mm) was 41.133 mm for Black, 41.160 mm for Dark gray, 40.880 mm for Gray and 40.459 mm for Light gray. Frequency (blinks/sec) was 0.211 for Black, 0.206 for Dark gray, 0.221 for Gray, and 0.238 for Light gray. Conclusions: Event Duration and average of Fixation Duration were the shortest for Dark gray and the longest for Light gray. In average Pupil diameter was the biggest Dark gray and the smallest for Light gray. Blink Frequency (blinks/sec) was the lowest for Dark gray and the highest for Light gray. Visual fatigue by brightness of letters on monitor display was the least for Dark gray followed by Black, Gray and Light gray.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.330-336
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• 1996

Quality characteristics of mash of takju prepared by different raw materials such at nonglutinous rice. glutinous rice, barley and wheat flour were investigated during fermentation. At the beginning stage of fermentation, ethanol content was in the range of $0{\sim}1.2%$ but it was increased to $9.8{\sim}11.6%$ after 16 day of fermentation. takju that was made of nonglutious rice with starter showed higher ethanol content than any other treatment. At the first stage, pH of takju that was made of nonglutinous rice without starter was 6.57 while other sample showed pH $5.04{\sim}5.80.$ There was no significant difference in pH value between treatments after 2 day of fermentation. Total acid was increased rapidly at the first stage of fermentation, and increased slowly after 2 day of fermentation. Takju that was made of nonglutious rice without of fermentation, and increased slowly after 2 day of fermentation. Takju that was made of nonglutious rice without addition starer showed higher total acid content than the other teratments. Total sugar contents were $19.18{\sim}20.23%$ at the beginning of fermentation, and decreased to $5.21{\sim}14.03%$ after 2-4 days of fermentation. Takju that was made of wheat flour showed higher value of total sugar during the fermentation. Reducing sugar contents of takju decreased with fermentation progressing to $0.2{\sim}0.5%$ after 16 day if fermentation. L value decreased during the fermentation. period and that of takju that was made of barley had lowest L value among the treatment. Alcohols, such as n-propanol ($nd{\sim}0.05\;mg/ml$), iso-butanol (0.02), iso-amyl alcohol ($nd{\sim}0.13$), n-hexanol ($nd{\sim}0.17$), n-heptanol ($nd{\sim}0.09$), and phenylethanol ($nd{\sim}0.02$) were detected. There were no alcohols detected at the beginning of fermentation, but their contents were increased during fermentation.