• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.4
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• pp.437-442
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• 2022

Squid jeotgal is a very popular traditional, salted, and fermented seafood in Korea. Due to the development of a distribution structure, a lot of imported squid jeotgal has recently entered Korea. In this study, we analyzed and compared the microbial contamination levels of domestic and imported squid jeotgal. The total viable bacterial count in domestic and imported jeotgal was 5.20 and 5.38 log CFU/g, respectively. The highest contamination level was 6.94 log CFU/g in one of the imported squid jeotgal samples. Coliforms were not detected in domestic jeotgal but were detected at 50% with 2.21 log CFU/g in imported jeotgal. Escherichia coli and Staphylococcus aureus were not detected (ND: <1 log CFU/g) in both domestic and imported jeotgal. All samples of jeotgal were negative for Bacillus cereus and Clostridium perfringens. The microbial contamination levels determined in the current study may be utilized as primary data to execute microbial risk assessments on domestic and (or) imported jeotgal.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.133-136
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• 2017

Fermentation plays a vital role in the nutritional enrichment of food. Korea has a long tradition of adding fermented food to the daily diet and jeotgal is one of the common fermented and salted foods in Korean cuisine. In our study, we added soymilk as an additive to squid jeotgal to improve its functionality. We mixed different concentrations of soymilk (2, 5, and 10 mg/g) with squid jeotgal samples, fermented them for one week, and then tested their antioxidant and anticancer activities to compare with those of squid jeotgal samples without soymilk additive. To investigate the anticancer characteristics, glutathione-S-transferase (GST)-pi enzyme assay was used. To test the antioxidant activities, various assays were performed, including 2,2-diphenyl-1-picryl hydrazyl free radical scavenging activity, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium saltradical cation scavenging assay, and reducing power assay. Samples fermented with a small amount of soymilk showed excellent anticancer activity. The addition of only 2 mg/g of soymilk to squid jeotgal inhibited the activity of GST-pi by almost 50% when compared with the sample with no addition. Moreover, no undesirable bitterness or astringency was noticed. Our results could help to improve the current food status of squid jeotgal and it could be used to reduce the risk of chronic disease along with its basic nutritional function.

• Journal of the Korean Society of Food Culture
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• v.17 no.4
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• pp.465-472
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• 2002

The effect of cooking(boiling, steaming and baking) and drying on the cholesterol content and formation of oxidized cholesterols and acid value in squid(Japanese flying squid, Todarodes pacificus) was studied. Cholesterol content of live squid meat varied with the portion sampled. The data from spectophotometric assay ranged from 263.2 mg/100g(mantle) to 315.8 mg/100g(tentacle). The cholesterol levels found for squid samples analyzed by gas chromatography(GC) were lower by 7% of total cholesterol for live squid meat and 24% for processed meat than those results by spectrophotometric assay. Cooking resulted some decrease in the initial total cholesterol content of raw meat from 10%(boiling for 5 min.) to 25%(steaming for 5 min.). The amounts of cholesterol remaining after baking were 68% for microwave oven samples and 64% for convection oven samples. Drying of raw tissue caused the greater reduction in cholesterol content than cooking but brought about no significant difference in samples stored for 6 weeks at $4^{\circ}C\;and\;20^{\circ}C$. Raw squid meats contained essentially no oxidized cholesterols, while the 22-hydroxychoesterol was detected in frozen meats. The additional oxidized cholesterols as cholestane-triol was indentified with 22-hydroxycholesterol in cooked samples. Sun dried meat stored at $4^{\circ}C\;and\;20^{\circ}C$ for 6 weeks had the three kinds of oxidized cholesterols such as 22-hydroxycholesterol, cholesta-3,5-dien-7-one and cholestane-triol. For the boiled and steamed squids, 10% higher acid value and 5% higher acid value respectively were observed but oven cooked samples resulted in a 50% higher acid value than raw samples. Squids had a 45% higher acid value than raw one during sundrying and presrevation at $20^{\circ}C$ but there was not a severe difference of acid value between $4^{\circ}C\;and\;20^{\circ}C$ stored samples.

• Korean Journal of Acupuncture
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• v.23 no.4
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• pp.135-145
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• 2006

Objectives and Methods : Using the 2-channel DROS SQUID (Korea Research Institute of Standards of Science, 1999), the present study was carried out to record changes elicited in the auditory cortex by acupuncture stimulus on right TE5 (Waiguan) and GB43 (Xiaxi). Needle-retention stimulation of TE5 and GB43 were done for acquiring the brain activities changed by acupuncture. Acupoint TE5 and GB43 is known to be effective for the treatment of ear-related disease, such as deafness and tinnitus, and to be suspected to be related to the auditory cortex. Auditory evoked magnetic fields were recorded hem the left hemisphere of five subjects, in response to contralateral ear stimulation by irregularly spaced 170 msec long 1kHz tone busts (Korea Research Institute of Standards of Science) Results and Conclusions : The result as follows. The latency and amplitude of SQUID MEG responses at the human auditory cortex changed by needle-retention condition on TE5 were 4msec and 9.2 fT, respectively, which were slower and smaller than those of no-acupuncture condition. The latency and amplitude of SQUID MEG responses at the human auditory cortex changed by needle-retention condition on GB43 were 7.2 msec and 1.6 fT, respectively, which were slower and larger than those of no-acupuncture condition. The latency of SQUID MEG responses at the human auditory cortex changed by needle-retention condition on GB43 condition was slower than that of TE5 acupuncture condition.

• Progress in Superconductivity
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• v.13 no.3
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• pp.139-145
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• 2012

Electric activity of cardiac muscles generates magnetic fields. Magnetocardiography (or MCG) technology, measuring these magnetic signals, can provide useful information for the diagnosis of heart diseases. It is already about 40 years ago that the first measurement of MCG signals was done by D. Cohen using SQUID (superconducting quantum interference device) sensor inside a magnetically shielded room. In the early period of MCG history, bulky point-contact RF-SQUID was used as the magnetic sensor. Thanks to the development of Nb-based Josephson junction technology in mid 1980s and new design of tightly-coupled DC-SQUID, low-noise SQUID sensors could be developed in late 1980s. In around 1990, several groups developed multi-channel MCG systems and started clinical study. However, it is quite recent years that the true usefulness of MCG was verified in clinical practice, for example, in the diagnosis of coronary artery disease. For the practical MCG system, technical elements of MCG system should be optimized in terms of performance, fabrication cost and operation cost. In this review, development history, technical issue, and future development direction of MCG technology are described.

• The Korean Journal of Food And Nutrition
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• v.16 no.2
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• pp.138-145
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• 2003

The effects of adding egg white, bovine plasma protein(bpp), gelatin and gluten on the rheological properties of squid meat paste product(squid meat kamaboko) were examined by the measurements of jelly strength, texture, moisture content, water holding capacity(WHC) and folding test. The optimum added levels for jelly strength of squid meat kamaboko were 4% of egg white, 5% of bovine plasma protein, 3% of gelatin and 4% for gluten. However, it is no increase that at added additives of over this concentrations were. Bovine plasma protein gave the highest jelly strength among the all additives at every concentration. Folding tests value of the optimum added levels were all B value. In this case moisture content and water holding capacity were 72.06∼73.78% and 88.53∼91.11% in jumbo squid, also flying squid were 71.91∼72.89% and 90.21∼93.25%, respectively. The additives were increased the jelly strength, hardness and water holding capacity(WHC), and these effects were eliminated by adjusting the water-content to the value of the control sample without additives.

• Journal of Biomedical Engineering Research
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• v.24 no.3
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• pp.159-165
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• 2003

We developed a 37-channel magnetoencephalogram (MEG) measurement system based on low-noise superconducting quantum interference device (SQUID) magnetometets, and operated the system to measure MEG signals. By using double relaxation oscillation SQUIDs with high flux-4o-voltage transfers, the SQUID outputs could be measured directly by room temperature preamplifiers and compact readout circuits were used for SQUID operation. The average field noise level of the magnetometers is about 3 fT/√Hz in the white region, low enough for MEG measurements when operated inside a magnetically shielded room. The 37 magnetometers were distributed on a hemispherical surface haying a radius of 125 mm. In addition to the 37 sensing channels. 11 reference channels were installed to pickup external noise and to form software gradiometers. A low-noise liquid helium dewar was fabricated with a liquid capacity of 30 L and boil-off rate of 4 L/d. The signal processing software consists of digital filtering, software gradiometer, isofield mapping and source localization. By using the developed system, we measured auditory-evoked fields and localized the current dipoles, demonstrating the effectiveness of the system.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.356-360
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• 1999

Effect of propolis treatment on the quality of dried squid were investigated. Dried squid containing 29% of moisture content were prepared and treated with 0.25% and 0.5% of propolis. Its total microbial count, TBA value and browning degree were assayed during 30 days. Total microbial count of dried squid treated with propolis were $72{\sim}80\;cells/g$, compared with control showing 25,000 cells/g. TBA values of dried squid were by $0.1{\sim}0.2$ lower than control. Browning degree was not different between treatment and control, but browning degree of propolis treatment showed lower than control through colorimetric analysis. These results suggested that quality of dried squid containing higher moisture could be improved by propolis treatment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.3
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• pp.329-336
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• 2015

We examined the effect of substituting squid meal and macroalgae with soybean meal in a commercial diet on the growth and body composition of juvenile abalone Haliotis discus hannai. We randomly distributed 2310 juvenile abalone into 33 rectangular plastic containers and fed them five experimental diets in triplicate as follows. The control diet (Con) consisted of 12% squid meal, 8% corn gluten and 20% soybean meal as protein source, wherein 10% ${\alpha}$-starch, 20% wheat flour, and 5% dextrin were carbohydrate source. The experimental diets, 50% squid meal (SM50), 50% squid meal and 50% macroalgae (SM50+MA50), and 100% squid meal and 50% macroalgae (SM100+MA50) were substituted with the same respective amounts of soybean meal. The fifth experimental diet consisted of the control diet plus 1% diatom powder (DP). We prepared two domestic (Domestic A and B) and two imported (China and Japan) abalone feeds. Finally, we prepared Undaria and sea tangle. We found that the weight gain of abalone fed the Con, DP, and China and Japan diets was significantly greater than that of abalone fed Undaria and sea tangle. We conclude that the substituting squid meal and macroalgae with soybean meal in abalone feed has limited benefits, but supplementing diets with 1% diatom powder is effective in improving weight gain.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.4
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• pp.312-320
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• 1993

Low-salted and fermented squid products, squid jeotkal was prepared and fermented at $10^{\circ}C$. During fermentation of squid, microbiological and chemical changes were examined. Sensory evaluation was also carried out. After 20 days of fermentation, taste and flavor of the squid jeotkal containing $10\%$ NaCl were proven to be the best; in contrast, the jeotkal with $7\%$ NaCl exhibited the highest sensory score. At the period showing the best flavor and taste, viable cell count reached to $10^8/g$. Throughout the fermentation period, types of microorganisms isolated were significantly different in squid jeotkal of different salinity. In general, protease producer and bacteria producing components of jeotkal-flavor and organic acids more likely contributed to producing the jeotkal of the best quality. pH of the squid jeotkal with $10\%$ salinity maintained under pH 7.0 throughout the fermentation periods; however, in the case of the jeotkal with $7\%$ salinity, pH increased over pH 7.0 after day 25. Similar tendency was observed in the results from VBN and hypoxanthine formation. Total nitrogen was decreased as fermentation proceeded; in contrast, total free amino acids were increased.