• Journal of the Korean Society of Food Science and Nutrition
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• 제20권6호
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• pp.609-614
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• 1991

Thermal stability and quality change during storage of red pepper oleoresin were studied. Upon heat treatment, carotenoids in oleoresin from red pepper were more stable under nitrogen than air. In the thermal stabilities, the presence of air at $100^{\circ}C$ for 3 hours and 10 hours were 69.1% and 42.3%, respectively ; whereas, in the presence of nitrogen, 95.4% and 92.3%, respectively. In contrast, capsaicin was comparatively stable upon heat treatment in the presence of air. The retentions of capsaicin at $100^{\circ}C$ for 3 hours and 10 hours were 84.7% and 81.3% with air, those were 90.7% and 87.5% with nitrogen, respectively. Color appearance showed close relation to the stability of total carotenoids during 60 days storage at varying temperatures ; $5^{\circ}C,\;25^{\circ}C\;and\;40^{\circ}C$ were 69.4%, 48.0% and 35.1%, respectively. The degradation of total carotenoids during storage could be interpreted as a first order reaction. The activation energy obtained from the Arrhenius plot was 5.03 kcal/mole. Conversely, capsaicin was very stable under storage temperatures. More than 90% of capsaicin was remained upon completion of storage. In the mean time, pH of oleoresin was increased slightly as increasing storage temperatures.

• Journal of the Korean Society of Food Science and Nutrition
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• 제31권2호
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• pp.221-224
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• 2002

This study was to explain the properties of acorn sediments and characteristics in the texture of acorn mooks due to the differences in preparing conditions of acorn sediments. The hardness of mook increased at 4$^{\circ}C$ during storage. The increase rate of acorn mook's hardness after storage for 24 hrs at 4$^{\circ}C$ were higher than those of others. X-ray diffraction of the retrograded acorn mooks was little different during storage at 4$^{\circ}C$. The syneresis of acorn mook was decreased with increasing the soaking treatment. The syneresis (%) of nontreated sample (0-0) was larger than those of the others.

• Microbiology and Biotechnology Letters
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• 제18권1호
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• pp.56-60
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• 1990

A bacterial strain of Brevibacterium sp. CHI was isolated from soil and used to produce an enzyme (nitrile hydratase) necessary for carrying out the bioconversion of acrylonitrile to acrylamide. Various immobilization methods and enzyme stability were investigated. The nitrile hydratase showed the maximum stability at pH 7 for the free cells. EDTA and phenyl methyl sulfonyl fluoride were selected as the protease inhibitor and the enzyme stability was evaluated by changing inhibitor concentration. Acrylamide beads were the best carriers among four carriers we tested in terms of stability and physicoehemical strength. The storage stability of the immobilized cells decreased with increasing acrylamide concentration of the gel phase at 4$^{\circ}C$, and was very low at acrylarnide concentration above 25%.

• Journal of the Korea Institute of Information and Communication Engineering
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• 제23권8호
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• pp.923-929
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• 2019

The stability of the propulsion system is crucial for the autonomous vessel. Multiple power generation and propulsion systems should be provided for the stability of the propulsion system. High power generation capacity is calculated for stability, resulting in economical decline due to low load operation. To solve this problem, we need to optimize the power system. In this paper, an OPMS for electric propulsion ship is constructed. The OPMS consists of a hybrid power generation system, an energy storage system, and a control load system. The power generation system consists of a dual fuel engine, the energy storage system is a battery, and the control load system consists of the propulsion load, continuous load, intermittent load, cargo part load and deck machine load. The power system was constructed by modeling the characteristics of each system. For the experiment, a scenario based on ship operation was prepared and the stability and economical efficiency were compared with existing electric propulsion ships.

• Korean Journal of Food Science and Technology
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• 제51권6호
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• pp.610-614
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• 2019

The effect of broccoli extracts on the storage stability of red beet extracts under various conditions (temperature, light condition, and pH) was analyzed. Regardless of the pH and light conditions, the absorbance of the red beet pigment at 537 nm was relatively stable (less than 10% reduction) at 4℃ for up to 5 days. The absorbance of the control extracts was rapidly reduced during storage at an ambient temperature in the dark, but the degree of reduction was relatively low at pH 3.8. As a positive control, the addition of vitamin C to the control extracts slightly inhibited the reduction (40% reduction), but the degree of the inhibition was much higher (15% reduction) with the addition of broccoli extracts (in 70% ethanol). Among all the samples, the addition of the broccoli floret extracts using 70% ethanol was the most effective method for the enhancement of the storage stability of red beet pigment at an ambient temperature in the dark.

• Journal of the Korean Society of Food Science and Nutrition
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• 제32권4호
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• pp.549-554
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• 2003

This study was conducted to investigate the effect of storage atmosphere sterilization using acidic electrolyzed water for table grapes (Vitis labrusca L.). ‘Campbell Early’ and ‘Sheridan’ grapes were stored at $0^{\circ}C$ for 12 weeks under the atmosphere that was passed through an acidic electrolyzed water for sterilization. Storage atmosphere sterilization using acidic electrolyzed water did not influence on the changes in soluble solids, titratable acidity, soluble tannins, anthocyanins, ethanol, acetaldehyde and organoleptic quality attributes including color, aroma, texture, juiciness and sweetness of both varieties during storage. Growth of bacteria and fungus in grapes during storage, however, was inhibited by storage atmosphere sterilization. These results suggest that the storage atmosphere sterilization using acidic electrolyzed water can be utilized for improving the storage life of table grapes.

• KSBB Journal
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• 제14권1호
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• pp.91-95
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• 1999

The objective of this work was to improve bioluminescence stability of Photobacterium phosphoreum when it stored in view of developing continuous on-line monitoring system for pullutants. Long-term experiments were made to determine the effect of immobilization and storage temperature on the maintenance and stability of bioluminescence from luminescent bacteria. The immobilized cells of P. phosphoreum were compared with free cells in terms of maintenance of bioluminescence at room temperature. The bioluminescence of cells immobilized showed higher bioluminescence intensity that free and strontium bioluminescence stability was investigated with free and immobilized cells stored at $20^{\circ}C,\; 4^{\circ}C,\; -20^{\circ}C\;and\;-70^{\circ}C$for 20 days. Both free and immobilized cells stored at $4^{\circ}C$ emitted a stable bioluminescence while the bioluminescence markedly decreased with those stored at $20^{\circ}C,\;-20^{\circ}C\;and\; -70^{\circ}C$.

• Proceedings of the Korean Information Science Society Conference
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• 한국정보과학회 2001년도 가을 학술발표논문집 Vol.28 No.2 (3)
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• pp.64-66
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• 2001

대용량, 고속의 멀티미디어 서비스가 일반화됨에 따라 저장장치 또한 대용량화되고 있다. 그러나 여전히 저장장치의 늦은 입출력 속도와 오류로 인해 시스템 전반의 성능에 영향을 미치고 있으며 대용량화로 인한 관리의 부담은 더욱 증가하였다. 본 논문은 소프트웨어 RAID와 LVM 기반의 네트웍 저장 장치의 구현에 관한 것이다. 소프트웨어 RAID를 사용하여 저장장치의 성능과 안정성을 높이고 LVM을 사용하여 저장장치의 관리를 쉽게 할 수 있다. 리눅스 커널 버전 2.4에서 제공하는 이러한 기능들을 사용함으로써 적은 비용으로 안정적이며 고성능의 저장장치를 구현할 수 있으며 관리가지 편리한 네트웍 저장장치를 구축할 수 있다.

• Korean Journal of Food Science and Technology
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• 제26권6호
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• pp.824-827
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• 1994

Sardine oil was vacuum-steam deodorized at $170^{\circ}C$ with acid (acetic and citric acid) and ethanol solution as steam sources. Glycerol was added to fish oil to remove volatile odorous constituents. The storage stability of deodorized fish oil was determined by totox value, secondary parameter obtained from peroxide and anisidine values. Both deodorization with acetic acid solution and addition of glycerol to the oil resulted in improved storage stability. The totox values of fish oil deodorized with water, glycerol+water and glycerol+acetic acid solution were 936, 611, and 443, respectively after 10 days at $30^{\circ}C$. The result showed that acetic acid seemed to destroy the odorous constituents and glycerol accelerated the removal of odorous constituents, such as amines in fish oil.

• Korean Journal of Food Science and Technology
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• 제37권4호
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• pp.597-602
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• 2005

Quality factors of emulsified ginseng drink were determined during storage at various temperatures, and its shelf-life was predicted based on changes in emulsion stability, acidify, viscosity, and yellowness. Viscosity was highly dependent on storage temperature. Emulsion stability changed rapidly during early storage period (1st step), then slowly thereafter (2nd step). $Q_{10}$ values of emulsion stability were 2.50 and 1.38 for 1st and 2nd steps, respectively. Viscosity, acidity, and yellowness showed $Q_{10}$ values of 3.45, 1.77, and 1.99, respectively. Although $Q_{10}$ value of 2 has been generally used to predict shelf stability of food materials, our results suggest adopting same $Q_{10}$ value to predict shelf stability of emulsified ginseng drink is not appropriate.