• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.478-485
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• 2017

The effect of high carbon dioxide and ethylene treatment on postharvest ripening regulation of red kiwifruit (Actinidia melanandra) was investigated during cold storage. Physio-chemical properties such as weight loss, firmness, SSC, acidity, and market quality were analysed in red kiwifruit held at $10^{\circ}C$ compared to the fruit treated with carbon dioxide and ethylene during 75 days of storage. No significant weight loss was detected in red kiwifruit treated with carbon dioxide until 75 days of storage while the most rapid loss was found in fruit treated with ethylene. In ethylene-treated fruit, the firmness was dramatically reduced from 4.2kg on the first day to 1.2 kg after 27 days of storage at $10^{\circ}C$. However, the firmness of the carbon dioxide-treated fruit was 1.8kg after 54 days of storage. The highest level of SSC(%) was investigated within the 27 storage days at $10^{\circ}C$ for fresh red kiwifruit treated with exogenous ethylene, whereas the carbon dioxide-treated fruit exhibited a greatly increased SSC after 64 days. The carbon dioxide-treated red kiwifruit maintained statistically(p<.01) higher levels of acidity compared to the control and the exogenous ethylene-treated ones during 41 days of storage at $10^{\circ}C$. The SSC/Acid ratio of fruit treated with carbon dioxide was significantly lower (p<.01) maintained than the other two treatments (ethylene-treated and control fruit)throughout the 75-day experiment. Based on the quality characteristics of postharvest red kiwifruit, it could be concluded that the carbon dioxide treatment significantly delayed the ripening process and maintained the market quality of harvested red kiwifruit, which can be a potential application for commercial use in the kiwi industry.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.313-317
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• 1997

To assess the physiochemical characteristics of greenhouse Satsuma mandarin (Citrus unshiu Marc. var, miyakawa) produced in Cheju, were analyzed chemical compositions for fruits, external and internal factors influencing the edible quality. Changes in organoleptic value according to brix and acid content were also evaluated. The ratios of sucrose : glucose : fructose in citrus juice were 2 : 2 : 1.5. Citric acid as the main acid in the juice represented about 70% of total organic acid. Most of the amino acids were found to be nonessential amino acids. Deep yellow color of the citrus peel showed a significant relationship(r=0.563) with brix/acid ratio of the citrus juice, indicating the ripeness of the fruit. Since the acid content showed highly negative statistical relationship(r= -0.882) with the pH value of the juice, the pH value appears to be a simple indicator for the sourness of the fruit in the field test. The fruits were divided into 9 groups based on the brix/acid contents for sensory evaluation. The palatability patterns of each group changed depending on the acid content. The optimal ranges of brix/acid content for acceptable taste were 11 and $0.5{\sim}1.0$, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.256-261
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• 2017

The effects of temperature and length of cold storage on the quality maintenance of fresh "Gold" kiwifruit were investigated. Physio-chemical properties were analyzed in kiwifruit held at $2^{\circ}C$ and $6^{\circ}C$ temperatures compared to fruit at room temperature ($20{\sim}28^{\circ}C$) during 8 weeks of storage. Low temperatures ($2^{\circ}C$ and $6^{\circ}C$) significantly delayed softening and soluble solids content (SSC) accumulation compared to higher temperature ($20{\sim}28^{\circ}C$). Physico-chemical properties of fruits, including weight losses, firmness, SSC, titratable acidity (TA), SSC/TA ratio, and flesh color properties were monitored during storage. Fast firmness loss was detected in fruit stored at higher temperatures compared to low temperature ($2^{\circ}C$). Similar results were observed for acidity according to storage temperature and length of cold storage, whereas SSC increased to the limited values (%Brix) during storage. The soluble solids content (SSC) increased markedly during the first 60 days of storage and remained almost constant thereafter for all treatments. SSC accumulation rates decreased from 5 weeks after storage probably due to differences between initial and ripe kiwifruits, and SSC decreased with each passing week due to natural starch conversion over time. The SSC/acid ratio increased from 18 to 27 until 5 weeks after storage and then slowly declined in all kiwifruit stored at different low temperatures. Sensory evaluation results showed no differences in kiwifruit flesh color stored at two storage temperatures of $2^{\circ}C$ and $6^{\circ}C$.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.3
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• pp.82-91
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• 2007

Rural areas dominate country landscape, where the population is rich in traditional and natural heritage. Dangsan forests and Rural community forests (RCF) have been maintained by local residents for hundreds of years. However, many of these forests have been disturbed, and only small amount of Dangsan forests and the RCF remain due to the efforts of local residents. Recently, the remnants of Dangsan forests and RCF have been regarded as living traditional landscapes representing the cultural and rural background of Korea. But the value of Dangsan forests and the RCFs has not been recognized by many. This study aims to understand the characteristics and management status of Dangsan forests in Sungnam-ri, Wonju. Sungnam-ri has four villages, each of which is bordered by a Dangsan forest at the riparian buffer. Sungnam-ri has been selsected as a site for a rural village development project by the Ministry of Agriculture & Forestry of Korea. Sunghwanglim (the Upper Dangsan forest) is designated as Natural Monument No.93 and entrance is limited in this area. The size of Sunghwanglim is $21,133m^2$, and the major tree species are Kalopanax pictus (Dangsan tree, Divine tree), Pinus densiflora, Abies holophylla, Acer triflorum, Ulmus davidiana, Fraxinus rhynchophylla and Quercus serrata. In total, 124 trees with more than 40 cm in DBH are at this site. As for cultural activities, the Dangsan festival is held on April 8th and September 9th of the lunar calendar at shrines in the forests. Although other Dangsan forests are smaller than Sunghwanglim, they also have similar cultural activities. The landscape of the Dangsan forests have been managed for several hundred years by the local people, and they intend to continue maintaining the Dangsan forests for the purpose of festivals and other cultural activities. The findings in this study suggest that Dangsan forests have the potential for the development of rural villages and for the improvement of cultural and natural landscapes in Korea.

• Food Science and Preservation
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• v.19 no.1
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• pp.7-11
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• 2012

This study was conducted to determine the effects of the humidity and gas composition on the quality of satsuma mandarins during their heat treatment, in an effort to reduce their acidity. To come up with different humidity and gas conditions, various plastic films were used. The fruits were wrapped with an 18-${\mu}m$ high-density polyethylene (HDPE) punched film, a 30-${\mu}m$ low-density polyethylene (LDPE) film, or a 100-${\mu}m$ LDPE film just before treatment at $30^{\circ}C$ for 55 hours. After heat treatment, the titratible acidity (TA) was significantly reduced while the soluble-solid content (SSC) showed no differences, which resulted in increased SSC/TA ratios in all the treatments. The fruits that were not wrapped with a film, however, which had low RH, developed higher ethanol and acetaldehyde contents than those wrapped with an 18-${\mu}m$ HDPE punched film, which had high RH and a similar gas composition. Among the films, the higher the $CO_2$ concentration in the film was, the more the ethanol and acetaldehyde contents increased, which induced more off-flavor. It was thus concluded that high humidity and normal gas composition are favorable conditions for heat treatment to reduce the acidity of satsuma mandarins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.455-463
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• 2015

This study investigated the effects of low-dose electron beam irradiation treatment on the physicochemical and sensorial properties of imported navel oranges during storage at $20^{\circ}C$ for 12 days. The samples were irradiated at doses of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy, after which changes in color value, hardness, Brix/acid ratio, total sugar contents, reducing sugar contents, vitamin C contents, and sensory evaluation were investigated. There were no significant differences between non-irradiated and irradiated samples in terms of color value, Brix/acid ratio, total sugar contents, total reducing sugar contents, and vitamin C contents. Hardness of irradiated samples significantly decreased in the early storage period in an irradiation dose-independent manner, and the difference between non-irradiated and irradiated samples decreased again at the end of storage. For the sensory evaluation, there was no significant difference between non-irradiated and irradiated samples up to 0.6 kGy, and all sensory item scores decreased at the end of the storage period regardless of irradiation. These results suggest that electron beam irradiation below 0.6 kGy does not affect physicochemical and sensory properties during storage at $20^{\circ}C$. Thus, electron beam irradiation up to 0.6 kGy applied to imported navel oranges is the optimum dose for minimizing quality changes and disinfestation treatment.

• Journal of the Korean Society of Radiology
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• v.11 no.6
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• pp.539-545
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• 2017

This study examined the irradiation effect of high energy x-rays on the growth of sprout plants seeds. particularly with regard to acidity, salinity and sugar content change. The experimental groups were one day old sprout plants seeds irradiated with 6MV x-rays at doses of 2, 5, 8, 10 Gy using a linear accelerator. The control group was not irradiated. After two weeks, sprout plants were grown and harvested for component analysis. The acidity of the x-ray irradiated radish and red radish groups were significantly higher than that of the control group and bok choi and buckwheat groups lower than that of the control group. The salinity and sugar content of the x-ray irradiated 5 groups were significantly lower than that of the control group and Soybean and Red radish groups higher than that of the control group. The cause of plants component change were estimated to have occurred by generate basic ions and radiation sensitivity by moisture content. Further genetic studies will be needed to confirm the correlation between high energy x-rays and the cause of plants component change.

• Economic and Environmental Geology
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• v.24 no.4
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• pp.399-408
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• 1991

There are several tuff cones and tuff rings, now only apparent on the western shoreline in Cheju Island. The observation of their landform, bedform, particle size and sorting reveals that these deposits are mainly emplaced by base surges and/or slurries originating from Surtseyan eruption which is attributed to explosive hydrovolcanism influenced by interaction of magma with external water. These are subdivided into two groups based on the plateau basalt. It is recognized that the distal limb of early tuff cones and ring at Dangsanbong, Dansan, Sanbangsan and Hwasun (lower group) are overlain by plateau basalt, on which later tuff rigns at Suwolbong and Songaksan(upper group) further extend the distal limb from each vent. The tuff cones and tuff rings are closely associated with the evidences which shelly fragments are comprised within them, and reworked tuffs, raised beach deposits, Sinyangri formation and littoral cones are deposited around them. The evidences suggest that the Surtseyan eruption resulted from direct or indirect interaction of magma with sea water.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.191-200
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• 2014

This study aims to analyze the current status of government-designated cultural heritage that are protected as sacred natural sites, focused on natural monuments and scenic sites, and provide basic research for these cultural heritage to be included in the protected area category. First, among natural cultural heritage that are designated and protected by Cultural heritage Protection Law, there are 40 scenic sites and 126 natural monuments that have been selected as sacred nature sites. Second, the study showed that sacred nature sites are sacred places that have been long associated with happiness and misfortune of the villagers, including Dangsan Forest, Seunghwanglim(Forest), and, as physical environment and combination of cultural value, rules, and attitude and belief system toward the land that protect the people. The unique folk beliefs of the region provide strong protection of the place. Third, although the natural monuments of old and large trees are not included in the protected area as they are recognized sparsely, but can be designated as world protected area as protected areas are set around sacred nature sites. Fourth, in order to be included in IUCN category, sacred natural sites of scenic sites will need to be managed by specific categories of each area according to the interior status of the designated areas and maintain the sustainability of the natural heritage by protecting both physical and spiritual elements.

• Applied Biological Chemistry
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• v.42 no.2
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• pp.147-151
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• 1999

Quality characteristics of Satsuma mandarin (Citrus unshiu Marc. var. okitsu) harvested in early December according to production areas and sea level altitude of Cheju were investigated. Soluble solids and flesh ratio were $9.06{\sim}12.98,\;77.32{\sim}81.27%$ on citrus fruits harvested in orchards located below 100 m sea level (lower area), and were $10.16{\sim}12.26,\;75.00{\sim}81.55%$ in orchards 150 m sea level altitude (higher area), respectively. Acid content of citrus juice was $0.83{\sim}1.21%$ in fruits harvested in lower area, and was $0.94{\sim}1.34%$ in higher area except Hankyung-myun area. The differences of soluble solids and acid contents by harvesting periods for 10 days were 0.91 and 0.82 for soluble solids; 0.15 and 0.13% for acid contents, respectively. In proportion to late harvesting, Brix/acid ratio and fruit quality were improving. Soluble solids of fruits harvested from lower area were higher than those of fruits from higher area, but acid contents were lower in fruits from lower area than in fruits from higher area. In sensory evaluation on fruit appearence, the differences between two altitudes were not clear, but panelists marked higher points on fruits harvested in main production areas, Seogwipo-si and Namwon-eup which are southern areas. Fruit quality harvested in Seogwipo-si areas showed better quality than fruits from other harvested areas.