• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.300-304
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• 1994

To predict quality change of Kochujang distributed in the market, physicochemical properties were observed during storage at $13^{\circ}C$, $27^{\circ}C$ and $37^{\circ}C$ for 240 days. Moisture, crude protein and capsaicin contents were nearly constant for storage at the selected temperatures. Amino nitrogen, value of surface color and pH were decreased during storage while ammonia nitrogen and titratable acidity were increased. Storage temperature affected quality change significantly as higher temperature showed clear increase or decrease phenomena of above factors. Number of total cell count was not changed significantly, and fungi was not detected. From the correlation coefficient among physicochemical properties and sensory evaluation scores, the highest correlation was obtained in amino nitrogen content and sensory score. Degradation of amino nitrogen was a first order reaction, and the $Q_{10}$ value calculated from reaction constant was 2.98. Also, activation energy for the destruction of amino nitrogen calculated from Arrhenius equation was 15.34 Kcal/mole.

• Journal of the Korean Vacuum Society
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• v.1 no.3
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• pp.332-335
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• 1992

초고진공 시스템에 있어서 시스템을 대기압으로 바람을 넣은 후 정상상태로의 신 속한 원상회복을 위하여 건조질소 통풍(venting) 장치를 고안 제작하였다. 이 장치는 액체 질소 저장통, 증발기 및 여과기로 구성되어 있다. 이 장치에 의한 통풍효과와 다른 방법에 의한 통풍효과를 가스 방출률 측정을 통하여 정성적으로 비교 분석하였을 때, 본 장치가 가 장 낮은 가스 방출률과 가장 빠른 진공회복을 보여주었다.

• The Korean Journal of Food And Nutrition
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• v.14 no.3
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• pp.204-210
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• 2001

전통수산 발효식품인 젓갈은 부패를 억제하기 위하여 20∼25%의 식염을 첨가하므로 짠맛이 강하고 성인병 유발과 유관하다는 단점이 있으므로 저식염 젓갈이 개발되고 있으나 저염 젓갈류는 비린내와 부패취가 강하여 기호도가 떨어질 뿐만 아니라 발암성 N-nitosamine(NA)의 생성 가능성이 높아지게 된다. 본 연구에서는 저염 젓갈의 저장성, 기호성 유지 및 NA생성을 억제코져 두류(대두, 검정콩) 및 허브류(애플민트, 페파민트, 레몬밤 및 스파아민트)의 에탄올 추출물을 각각 첨가한 저염 멸치젓을 제조하여 110일간 숙성시키면서 품질과 관련된 여러 인자 및 NA 생성여부를 실험하였다. 저염 멸치젓 숙성 중 PH, 염도 및 산도는 모든 실험군에서 숙성 110일까지 큰 변화를 보이지 않았다. 휘발성 염기질소는 저장기간에 따라 점차 증가하는 경향을 보였는데 애플민트 추출물 첨가군이 가장 큰 폭으로 증가하였다. DMA 및 TMA 질소도 증가하는 경향을 보였는데 숙성 75일째부터 그 증가폭이 두드러졌다. 질산염 질소는 젓갈 숙성 중 점차 증가하는 경향을 보였으며, 아질산염 질소는 약간 증가하는 경향이었다 NA는 N-nitrosodi-methylamine(NDMA)만이 검출되었으며 대조군에 비하여 전 실험군에 더 낮은 함량이었으며 이때 평균회수율은 63.9∼99.7%였다. 허브 추출물 첨가군에서 대조군에 비하여 월등히 낮은 함량은 NDMA가 검출되었는데, 특히 페파민트 추출물 첨가군에서는 숙성 75일까지 흔적량에 불과하였다.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.715-721
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• 2011

This study was conducted to estimate aboveground biomass and nitrogen storage potential of tree species-eight clones of a poplar and hybrids, one clone of Salix alba L., dawn redwood (Metasequoia glyptostroboides Hu and W.C. Cheng), yellow poplar (Liriodendron tulipifera L.), Okamoto maple (Acer okamotoanum Nakai), and pin oak (Quercus palustris $M{\ddot{u}}nchh.$)- after treating with liquid pig manure. Stems showed the highest percentage of aboveground biomass, and followed by branches and leaves. Nitrogen content in aboveground biomass components was the highest in leaves, and followed by branches and stems. Average aboveground biomass production was higher in the clones and species treated with manure than those of not treated, 30 ton/ha and 16 ton/ha, respectively. In the manure-treated site, clone 'Dorskamp' of Populus deltoides${\times}$Populus nigra showed the highest aboveground biomass (48.3 ton/ha). Average nitrogen storage potential was superior in the clones and species treated with manure than those of not treated, 159 kg/ha and 90 kg/ha, respectively. Clone 'Dorskamp' also showed the greatest nitrogen storage potential (286.5 kg/ha) among tested tree species. Therefore, 'Dorskamp' is the most suitable clone for treating liquid pig manure, but additional studies are needed to determine any damages or tolerance from the treatment.

• Journal of Mushroom
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• v.18 no.4
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• pp.339-343
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• 2020

This study aimed to optimize total nitrogen (TN) content in the medium and the growth temperature to improve the shelf life of Pleurotus eryngii Keneutari No. 2. We investigated the growth characteristics and changes in the O2/CO2 content in polypropylene film and performed sensory evaluations during cold storage under 1.5%, 1.8%, 2.1%, and 2.4% TN and at temperatures of 9℃, 12℃, and 15℃. The diameter and weight of the fruit bodies tended to increase with increasing nitrogen content, regardless of the growth temperature, and the highest weight per bottle (149.5 g) was obtained at 12℃ and 2.4% TN. Regardless of the nitrogen content, leaf color deepened with decreasing temperature. The gas concentration in the film, which changes depending on storage time, was maintained for the longest period at 9℃ and 2.1% TN. The sensory evaluation revealed no difference between the different nitrogen conditions tested, and the odor, discoloration, and decay were similar at 15℃ and 9℃ until day 28 of storage.

• Journal of Food Hygiene and Safety
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• v.20 no.2
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• pp.89-97
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• 2005

The influence of different storage temperature and packaging methods on the flying cultured eel bone were investigated. The acid values, peroxide values and fatty acid composition were measured during storage 20$^{\circ}C\;and\;40^{\circ}C$ for 60 days. The lipid oxidation was rapidly progressed with the increased temperature. The addition of oxygen absorber remarkably repressed lipid oxidation during storage of the living cultured eel bone at $20^{\circ}C\;and\;40^{\circ}C$, followed by $N_{2},\;BHA,\;\alpha$-tocopherol and control. The monounsaturated fatty acid content was the highest in the frying cultured eel bone, followed by saturated fatty acid and polyunsaturated fatty acid. The major fatty acids were oleic acid, palmitic acid and linoleic acid. The saturated fatty acids increased with the rise of storage temperature and prolonging the storage period, while monounsaturated fatty acid and polyunsaturated fatty acid were decreased. The changes of fatty acid composition were the lowest in sample by packing with oxygen absorber, followed by packing $N_{2},\;BHA,\;\alpha$-tocopherol and control. from the result of sensory evaluation, sample by packing with oxygen absorber were rated as higher quality than the others.

• Journal of Ginseng Research
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• v.25 no.1
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• pp.45-52
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• 2001

The storage stability of fresh ginseng packaged individually in a soft film bag was more enhanced as the soft film with lower oxygen permeability was used, while the optimum water vapor permeability for enhancing the storage stability of fresh ginseng was estimated 3.5 g/m$^2$$.$day$.$90% RH when using the soft film with low oxygen permeability of 3.6∼5.4 cc/m$^2$$.$day$.$atm. The storage stability of the individually packaged fresh ginseng was also enhanced when the soft film bag was filled with carbon dioxide-oxygen-nitrogen (25:5:70) miked gas but the vacuum packaging exhibited little effect for the enhancement of storage stability of the fresh ginseng.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1321-1326
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• 1998

Extraction and storage conditions of oleoresin were studied from root portion of peeled garlic, an waste of garlic industry. Extraction with ethanol and methanol showed an high solid yields of $27{\sim}37%$ at the temperature range of $30{\sim}50^{\circ}C$. Two hours of extraction were found to be economic because of no significant increase in furthur extraction. Storage of the oleoresin under anaerobic condition such as vaccum or nitrogen resulted in a less changes in pH, total acidity, color and thiosulfinate content, than those changes under aerobic condition. Most of the thiosulfinate was decreased for all conditions after 14 days of storage at $25^{\circ}C$. Glucose and sucrose were increased and most of organic acids were decreased during storage under nitrogen condition. Addition of ascorbic acid and cysteine into oleoresin retained the garlic flavor, effectively.

• Korean Journal of Food Science and Technology
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• v.19 no.3
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• pp.195-199
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• 1987

Changes in quality characteristics of boiled-dried anchovy during storage under different packaging conditions for 6 months were studied. For the packaging trials, kraft paper (KP), kraft paper laminated with 0.03 mm polyethylene film (KP/PE) and 0.1 mm polyethylene film with nitrogen gas substitution ($N_2$ gas) were employed. In case of KP, the reaction of thiobarbituric acid, browning rate of lipid oxidation and Hunter color values of L, a and b were remarkably higher than those packaged in KP/PE or $N_2$ gas. Judging from organoleptic evaluation boiled-dried anchovy could be preserved in acceptable condition for 6 months at $5^{\circ}C$in all packaging cases and, at room temperature, 3 months in KP and 4 months in KP/PE or $N_2$ gas. From the standpoint of quality stability by packaging methods, it was concluded as good in sequence as $N_2$, gas, KP/PE and KP. The results suggest that the quality of boiled-dried anchovy be well preserved by packaging with inert gas ($N_2$ gas) or impermeable material to vapors and oxygens.

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.67-72
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• 2005

To investigate the feasibility of a new concept of storing Liquefied Natural Gas (LNG) in a lined hard rock cavern, and to develop essential technologies for constructing underground LNG storage facilities, a small pilot plant storing liquid nitrogen (LN2) has been constructed at the Korea Institute of Geoscience and Mineral Resources (KIGAM). The LN2 stored in the cavern will subject the host rock around the cavern to very low temperatures, which is expected to cause the development of an ice ring and the change of ground condition around the storage cavern. To investigate and monitor changes in ground conditions at this pilot plant site, geophysical, hydrogeological, and rock mechanical investigations were carried out. In particular, geophysical methods including borehole radar and three-dimensional (3D) resistivity surveys were used to identify and monitor the development of an ice ring, and other possible changes in ground conditions resulting from the very low temperature of LN2 in the storage tank. We acquired 3D resistivity data before and after storing the LN2, and the results were compared. From the 3D images obtained during the three phases of the resistivity monitoring survey, we delineated zones of distinct resistivity changes that are closely related to the storage of LN2. In these results, we observed a decrease in resistivity at the eastern part of the storage cavern. Comparing the hydrogeological data and Joint patterns around the storage cavern, we interpret this change in resistivity to result from changes in the groundwater flow pattern. Freezing of the host rock by the very low temperature of LN2 causes a drastic change in the hydrogeological conditions and groundwater flow patterns in this pilot plant.