• Journal of Biosystems Engineering
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• v.25 no.1
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• pp.33-38
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• 2000

This study was performed to investigate airtight storage characteristics of rough rice using airtight flexible pve container. A storage test of rough rice of 4 tonnes was carried out to determine the changes of gas composition of air in the container, grain moisture content, air temperature and relative humidity , the presence of insects ,germination rate, crack ratio , fat acidity , 1000-kernel weight, and brown rice recovery over storage period of 5 months in Suwon. Concentration of oxygen was decreased from 20% to 16% and carbon dioxide was increased of from 0.03% to 1.6%. The grain moisture content was decreased from 14.4%(w.b) to 14.1%(w.b) for 5 months storage period . Insect population levels were low but these increased after 5 months storage. Most of insects were dead, Fat acidity increased from 7.5(mg KOH/100g) to 10.2(mg KOH/100g). Other storage factors such as germination rate, brown rice recovery and 1000-kernel , and 1000-kernel weight slightly decreased and crack ratio was slightly increased. Qualities of rough rice during 5 months storage period under hemetic air conditions were maintained fairly good considering the above changes of quality factors during storage.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.14 no.2
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• pp.57-63
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• 2008

The effects of airtight containers and zipper bags on the freshness extension of pine nuts (Pinus koraiensis) were studied at 4 and $25^{\circ}C$. Changes in total microbial growth, 2-thiobarbituric acid(TBA), color, and sensory quality were evaluated during storage. Total bacterial counts of the samples continuously increased over 28 days for airtight containers and 56 days for zipper bags, and then decreased at 70 days because the lack of air could affect the inhibition of the aerobic microbial growth. However no significant differences were observed between airtight containers and zipper bags. TBA values continuously increased with storage time, but there were no significant differences between the airtight containers and zipper bags during storage. Color changes and sensory evaluation analyses showed that the data revealed similar results for both packaging systems over the storage time. Therefore, it has been concluded that airtight containers and zipper bags could be used as a good packaging system to extend the shelf life of pine nuts by controlling the microbial growth, but the packaging systems of the airtight containers and the zipper bags was not significantly affect the quality parameters for 2-thiobarbituric acid(TBA), color, and sensory quality.

• Food Science and Preservation
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• v.2 no.1
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• pp.163-171
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• 1995

Organoleptic qualities were evaluated putting emphasis on flavor and color of white ginseng powders which were treated with ethylene oxide(EO) and gamma radiation(5, 10kGy) for microbial decontaminations. Immediately after treatments, there was no significant changes in the overall flavor and color of the samples between the nontreated control and both treatments. The color of even airtight-packaged samples, however, was changed(p<0.05) after 7 months of storage at 30$\pm$2$^{\circ}C$ when treated with EO and 10 kGy. These changes in color were confirmed by the instrumental determinations for the stored samples. Thus, it can be proposed that gamma Irradiation below 10kGy combined with airtight packaging is required for keeping the organoleptic quality of white ginseng powders for more than 6 months of storage.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1998.12a
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• pp.269-275
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• 1998

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.1
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• pp.19-25
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• 1992

This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.1
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• pp.19.1-19.1
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• 1992

This experiment was conducted to investigate chemical composition change and fermentation characteristics of orchardgrass, alfalfa or corn silage in the airtight silo for one year of storage. Two trials were conducted for two years. Fermentation characteristics of silages were evaluated by color, oder, texture and taste. Chemical composition of corn silage was not changed, and fermentation characteristics of this silage was favorable for 7 months of storage from December to June of the following year. In the aspect of dry matter loss and fermentation characteristics of silages, it is essential to maintain less than 70 or 60% of moisture contents in orchardgrass silage or alfalfa silage, respectively, for long term storage and feed quality stabilization. It is suggested that wilting treatment of orchardgrass or alfalfa and moisture contents of these silages are most important factors to determine silage quality.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.25 no.2
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• pp.31-35
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• 2019

Kimchi is a refreshing sour food which gives sour and carbonic acid taste of carbon dioxide produced during the fermentation process. So, carbon dioxide injection was tried to raise carbonic acid taste of kimchi stored in the airtight container. First, carbon dioxide injection times of a given gas supply system were determined experimentally to attain initial concentration of 80% for different solid/liquid ratios. Since carbon dioxide is dissolved in kimchi to decrease its concentration during storage, periodical carbon dioxide injection conditions were needed and determined to keep the $CO_2$ concentration above 70%. For the initial flushing to 80% $CO_2$ concentration in model system filled with water, the injection time ranged from 40 to 89 seconds for free volumes of 2-8 L. $CO_2$ injection conditions for the under-ripened storage at $10^{\circ}C$ consisted of longer time at more frequent cycles for watery kimchi than for Chinese cabbage kimchi. At $0^{\circ}C$ of subsequent ripened stage storage of watery kimchi, the periodical injection at 3 hour interval was required because of continuous dissolution of carbon dioxide. However, Chinese cabbage kimchi did not require subsequent $CO_2$ injection during the ripened state storage and needed only flushing to 80% $CO_2$ at time of the container opening and closing. These results can be used as basic information for the programmed control of $CO_2$ injection in the kimchi container system.

• Journal of Ginseng Research
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• v.18 no.2
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• pp.128-133
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• 1994

Color characteristics were investigated for white ginseng powder immediately and during storage following treatments of gamma ray or ethylene oxide (EO) for microbial decontamination. The variation in fatand water-soluble pigments of the sample was negligible immediately after both treatments, however an apparent increase was observed in the samples stored for four months at $25^{\circ}C$ and RH 90%, in the order of nontreated control, EO-fumigated, and 5 key-irradiated samples. Hunter's color a and b values of white ginseng powder increased slightly in proportion to irradiation doses, whereas EO fumigation caused a decrease in L value and an increase in a and b values of the sample, showing overall color difference (${\delta}^E$) of 1.8. Considering the higher ${\delta}^E$ in the higher RH conditions, airtight packaging and sterilization using like gamma ray were considered an effective means for maintaining high quality of color characteristics in stored white ginseng powder.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.2
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• pp.164-168
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• 2014

To determine the optimal storage method and longest possible storage period of Zostera marina seeds, we examined post-storage germination rates using different storage methods and periods for Z. marina seeds harvested in southern coast of Korea. Storage methods included in seawater at room temperature with air supply, seawater at $4^{\circ}C$, seawater at $30^{\circ}C$, an aquarium with continuous seawater circulation, seawater at room temperature in an airtight tank, a refrigerator at $-20^{\circ}C$, and a desiccator at room temperature. Germination rates of Z. marina seeds stored in seawater at $4^{\circ}C$ showed highest germination (52.0%), whereas those of seeds stored in seawater at room temperature and an aquarium were 27.4% and 17.7%, respectively. But the seeds stored in seawater at $30^{\circ}C$, a refrigerator, and a desiccator did not germinate. Storage periods were 10, 20, 30, 60, 180 and 240 days of storage. Z. marina seeds maintained germination rates of 46.4~52.4% until 10~60 days of storage, but showed rapidly decreasing germination rates after then and no germination after 240 days.

• Tribology and Lubricants
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• v.34 no.5
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• pp.197-207
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• 2018

Thermal deterioration of fuel due to long-term storage influences engine performance and causes malfunctions. Fuel stability is usually evaluated via heat resistance and thermal stability during a brief heat shock at high temperature; storage stability in this scenario means that there is very little change in the quality of the fuel during long-term storage. In addition, rubber-based products such as oil seals, O-rings, and rubber hoses can influence the quality of the fuel. When these rubber products are in contact with fuel, they can swell, mechanically weaken, and occasionally crack, thus leaking low molar weight rubber and additives including plasticizer and antioxidant into the fuel to degrade its properties and shorten its useful lifetime. This study determines the thermal stabilities of three kinds of synthetic fuels by evaluating their low temperature kinematic viscosities, chemical composition changes via GC analyses, gross heat of combustion, and color changes. We evaluate the compression set of O-rings by immersing one NBR and two FKM rubber O-rings in the three synthetic fuel samples in airtight containers at variable storage temperatures for six months; from this, we estimate the lifetimes of the O-rings using the Power law model. There were very little changes in the chemical compositions and gross heat of combustion after six months of the experiment. The lifetimes are thus dependent on the materials of the rubber products, and in particular, the FKM O-ring was calculated to have a theoretical lifetime of 200 to 5,700 years. These results indicate that the synthetic fuels maintain their physical properties even after long-term storage at high temperatures, and the FKM O-ring is suitable for long-term sealing of these fuels.