• The Journal of the Petrological Society of Korea
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• v.13 no.4
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• pp.179-190
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• 2004

Precambrian metamorphic rocks of Yeongyang-Uljin area, which is located in the eastern part of Sobaegsan Massif, Korea, are composed of Pyeonghae, Giseong, Wonnam Formations and Hada leuco granite gneisses. These show a zonal distribution of WNW-ESE trend, and are intruded by Mesozoic igneous rocks and are unconformably overlain by Mesozoic sedimentary rocks. This study clarifies the deformation history of Precambrian metamorphic rocks after the formation of gneissosity or schistosity on the basis of the geometric and kinematic features and the forming sequence of multi-deformed rock structures, and suggests that the geological structures of this area experienced at least four phases of deformation i.e. ductile shear deformation, one deformation before that, at least two deformations after that. (1) The first phase of deformation formed regional foliations and WNW-trending isoclinal folds with subhorizontal axes and steep axial planes dipping to the north. (2) The second phase of deformation occurred by dextral ductile shear deformation of top-to-the east movement, forming stretching lineations of E-W trend, S-C mylonitic structure foliations, and Z-shaped asymmetric folds. (3) The third phase deformation formed I-W trending open- or kink-type recumbent folds with subhorizontal axes and gently dipping axial planes. (4) The fourth phase deformation took place under compression of NNW-SSE direction, forming ENE-WSW trending symmetric open upright folds and asymmetric conjugate kink folds with subhorizontal axes, and conjugate faults thrusting to the both NNW and SSE with drag folds related to it. These four phases of deformation are closely connected with the orientation of regional foliation in the Yeongyang-Uljin area. 1st deformation produced regional foliation striking WNW and steeply dipping to the north, 2nd deformation locally change the strike of regional foliation into N-S direction, and 3rd and 4th deformations locally change dip-angle and dip-direction of regional foliation.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.374-380
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• 2006

For the improvement of Gulbi processing, yellow corvenia was salted by 2 different time (5 hours, low salted and 5 days, high salted) and then dried in the sun and stored for 5 and 21 days, respectively. Malonaldehyde contents and fatty acid composition were analyzed during Gulbi processing. The moisture contents of yellow corvenia were significantly decreased during processing procedure. The salt contents were 10 folds higher in 5 day-salted sample than in 5 hour-salted one. The salt contents showed reversed tendency to moisture contents. There was little change in pH during storage. The contents of malonaldehyde in yellow corvenia were increased during Gulbi processing and storage. Its contents were higher in 5 day-salted sample and exterior parts than 5 hour-salted sample and interior parts of Gulbi. The fatty acids composition showed higher oleic acid $(C_{18:1})$, palmitic acid $(C_{16:0})$ and docosahexaenoic acid $(C_{22:6})$ than any other fatty acids in Gulbi. Saturated fatty acids were increased but unsaturated fatty acids were decreased during Gulbi processing. After 21 days storage, unsaturated fatty acids remaining ratio in 5 hour-and 5 day-salted sample were 1.39 and 0.99 respectively. The contents of unsaturated fatty acids were dramatically changed as salt concentration increased during storage than in processing.

• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.168-174
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• 2005

Various changes of physico-chemical characteristics of chilled plaice muscle during storage at $4^{\circ}C$ in vacuum and aerobic packaging methods were examined. As a storaging period become longer, Hunter L, a, b value changes slightely. However, no differences were observed between vacuum and aerobic packaging method. The hardness of plaice muscle after death was $2,232\;dyne/cm^2$. The hardness of vacuum packaged plaice muscle storaged for 4 days was similar to that of aerobic packaged plaice muscle storaged fur 14 days. MFI(Myofibrillar Fragmentation Index) of aerobic and vacuum packaged plaice muscle showed maximum value at storage for 4days and 7 days, respectively. Mg-ATPase activities of mypofibril were increased gradually both of all during storage days. But that of MF from aerobic packaging plaice muscle was higher than that of vacuum packaging plaice muscle.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1715-1724
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• 2015

The combined effects of a sanitizer mixture solution and antimicrobial ice on the quality of salted Chinese cabbages were examined. Salted Chinese cabbages were treated with a sanitizer mixture (comprised 50 ppm aqueous $ClO_2$ and 0.5% citric acid), packed in 2% brine and antimicrobial ice, and stored for 12 days at 4 and $10^{\circ}C$. Microbiological data on the salted Chinese cabbages after washing with the sanitizer mixture indicated that the populations of total aerobic bacteria, and yeast and molds decreased by 2.20 and 1.28 log CFU/g after treatment with the sanitizer mixture. In addition, coliforms population of salted Chinese cabbage after 12 days storage at $4^{\circ}C$ in the combined mixture of the sanitizer and antimicrobial ice was 3.22 log CFU/g, which was a significantly different from that of control (5.46 log CFU/g). The combined treatment of sanitizer mixture, antimicrobial ice, and low temperature at $4^{\circ}C$ suppressed reduction of pH and elevation of titratable acidity, resulting in delaying the growth of lactic acid bacteria. Differences in salinity, hardness, and Hunter's $L^*$, $a^*$, and $b^*$ values among treatments were negligible during storage at $4^{\circ}C$. Therefore, this study suggests that a combination of sanitizer mixture, antimicrobial ice treatment, and low temperature storage could improve the microbial safety and quality of salted Chinese cabbages during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.687-694
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• 2012

$Jeot-gal$ is a traditional Korean fermented seafood with a salt concentration of 15~20%. However, today's consumers prefer low-salted foods as they have become aware that high levels of salt cause hypertension and diabetes. In this study, the quality characteristics and shelf-life of low-salted squid $Jeot-gal$ were investigated at different fermentation temperatures and salt concentrations. The shelf-lives of 3%-salted squid $Jeot-gal$ fermented at -1, 4, and $10^{\circ}C$ were 45, 31, and 23 days, respectively, whereas those of 5%-salted squid $Jeot-gal$ were 52, 36, and 25 days. The DPPH radical scavenging activity of the ethanol extract of squid $Jeot-gal$ was stronger than that of the water extract. However, the other antioxidative activities, such as hydrogen peroxide and hydrogen peroxide radical scavenging activities, as well as enzyme inhibitory activities were very low at 20 mg/mL of water and ethanol extracts. Based on the results of the sensory evaluation, the quality of low-salted fermented squid $Jeot-gal$ was almost similar to that of commercial squid $Jeot-gal$ with a high salt concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1302-1309
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• 2003

Physicochemical and sensory characteristics of turnip pickles added with chitosan and/or beet water extract were investigated. Turnip root slices (4${\times}$1${\times}$0.5 cm) were salted with NaCl and CaCl$_2$, soaked into pickling solution, and then stored at 2$0^{\circ}C$. Throughout the whole storage periods, pH, acidity, saltiness and soluble solid content of three pickles (C, turnip pickle; CC, turnip pickle+chitosan; CBC, turnip pickle+chitosan+beet water extract) ranged to 3.1 ∼ 3.5, 1.5 ∼ 1.7%, 0.5 ∼ 0.7% and 24.5 ∼ 28.5$^{\circ}$Brix, respectively. There were no significant differences between three pickles in saltiness, anthocyanin and reducing sugar content. However, acidity and hardness of CC and CBC were higher than those of control C throughout the storage time. While Hunter's a value of CBC was higher than those of CC or C. Sensory results showed that the best edible time was the 14th day of storage, and at that time, scores of CC and CBC were higher in over-all preference (7.8 and 8.4) than those of C (6.1), and CC and CBC maintained good sensory qualities until 28th day of storage, compared to C (p<0.05).

• The Korean Journal of Food And Nutrition
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• v.27 no.5
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• pp.785-795
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• 2014

This study was conducted to develop low-salinity Kimchi with acetic acid, starters and fruits added for health and taste. The quality characteristics of the developed Kimchi by storage period and salt concentrations were investigated herein. The effects of salinity and fermentation temperature ($0^{\circ}C$, $5^{\circ}C$) on the quality characteristics of low-salinity Kimchi were investigated through physicochemical and microbiological analysis. The sensory characteristics are shown in the results below. The pH and acidity were quickly changed by higher temperature over longer storage periods, with gradual decrease in the pH accompanied with an increase in acidity. The microbiological analysis revealed increase in the total cell number regardless of the concentration and strain added during the storage period. Finally, test of the overall acceptability with regard to sensory characteristics according to the different strain sets in low-salinity Kimchi showed the average score for smell, salty taste and overall acceptability were highest in the hetero-fermentation strain group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.586-592
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• 2011

The storage quality of soybean sprouts washed with various electrolyzed waters was investigated. The washing solutions consisted of tap water (TW), sodium hypochlorite electrolyzed water (SHEW), and slightly acidic electrolyzed water (SAEW). The number of bacteria on the soybean sprouts after 5 min of exposure to TW, SHEW, and SAEW resulted in >0.5, 2.0, and 2.0 log CFU/g reductions, respectively. At both $4^{\circ}C$ and $25^{\circ}C$, the number of bacteria, weight loss ratio, and b value rapidly increased, and pH and L value rapidly decreased in soybean sprouts washed with TW. Whereas, the number of bacteria, pH, weight loss ratio, and color slowly changed in the soybean sprouts washed with SHEW and SAEW. Consequently, these results indicate that washing with electrolyzed water is an effective means of maintaining the quality and enhancing the shelf-life of soybean sprouts; both SHEW and SAEW reduced bacterial growth without affecting the other properties of soybean sprouts during storage.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.1
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• pp.15-25
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• 2023

Since the COVID-19 crisis, the use of disposable packaging materials and delivery services, which raise environmental and social issues with waste disposal, has significantly increased. Antimicrobial active packaging has emerged as a viable solution for extending the shelf-life of foods by minimizing microbial growth and decomposition. In this review article, we provide a comprehensive overview of current research trends in antimicrobial active film and coating published over the last five years. First, we introduced various polymer materials such as film and coating that are used in active packaging. Next, various types of antimicrobial (antibacterial, antifungal, and antiviral) packaging including essential oil, extracts, biological material, metal, and nanoparticles were introduced and their activities and mechanisms were discussed. Finally, the current challenges and prospects were discussed. Overall, this review provides insights into the recent advancements in antimicrobial active packaging research and highlights the potential of the technology to enhance food safety and quality.

• Journal of Nutrition and Health
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• v.15 no.1
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• pp.39-46
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• 1982

Nitrate accumulated in vegetables can, via $NO_2$ during storage and after their ingestion, cause the formation of methemoglobin and many of which are carcinogenic in human body. Especially such vegetables with the highest consumption in Korea as chinese cabbage and raddish frequently showed that high contents of nitrate and nitrite could accumulate. Therefore, pH and the content of nitrate and nitrite of Korean pickles made of upper vegetables, viz, Baiechu Kimchi, Yulmookimchi and Kakdooki were estimated during storage at the conditions of $5^{\circ}C$ and $25^{\circ}C Storage at $25^{\circ}C$ generally led to the more rapidly than that at $5^{\circ}C$. But changes of nitrite level showed very low variation in all tested Kimchi.