• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1051-1057
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• 2000

Gamma irradiation was applied to develop fermented shrimp product with lower salt concentration, high sensory quality and storage stability. Shrimp was prepared with 15 and 20% of salt and fermented at $15^{\circ}C$. The sample was irradiated for 15% added salt at the 4th week and for 20% at the 6th week during fermentation with 0, 5 and 10 kGy absorbed doses. The irradiation was applied at optimum stage of fermentation determined when the content of amino nitrogen(AN) arrived approximately 400 mg%. Chemical properties such as amino nitrogen(AN), volatile base nitrogen(VBN), trimethylamine(TMA) and neutral protease activity were examined during whole fermentation. The AN, VBN, TMA and protease activity were not affected immediately after gamma irradiation. The more NaCl concentrations and irradiation dose, the less content of chemical compounds and protease activity was found. From the results of chemical properties, it was concluded that fermented shrimp with 15% of salt and irradiated at 10 kGy before optimum fermentation, or 20% and 5 kGy or above were maintained the sound quality during storage compared with the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.8
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• pp.957-964
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• 2017

This study was carried out to investigate the effects of garlic extract on histamine reduction in mackerel meat stored at $4^{\circ}C$ and $15^{\circ}C$, respectively. The number of total bacteria in mackerel meat treated with 7.5% garlic extract was ten times lower than that of the control stored for 6 days of $4^{\circ}C$. However, there was no difference among the samples after 9 days of storage. Reduction of eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) contents was observed in the normal control group at both temperatures. However, contents of these two polyunsaturated fatty acids slightly increased in garlic extract-treated fish. Amounts of volatile basic nitrogen increased over time in the control group, but decreased in the garlic extract-treated meat, indicating that garlic extract might suppress decomposition. No histamine was detected initially in all samples. However, a small amount of histamine (42.87 mg/kg) was detected in the control at 3 days after storage at $4^{\circ}C$. Histamine content increased continuously with storage period but was lower in mackerel meat containing garlic extract, in which histamine suppression was proportional to the concentration of garlic extract. It can be concluded that garlic extract could be utilized to extend the storage period of mackerel.

• Journal of Food Hygiene and Safety
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• v.17 no.4
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• pp.193-200
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• 2002

Three species of fish such as yellow tail (Seriola quinqueradiata), bastard halibut (Paralichthys olivaceus) and black rockfish (Sebastes schlegeli) were exposed to the dinoflagellate, Cochlodinium polykrikoides, and quality changes of fish after death were investigated during the extended storage. The volatile basic nitrogen (VBN) and aerobic plate counts (APC) were determined in the muscles of fish, arid organoleptic change was evaluated in the kills, skins and muscles. APC in all the fish species did not change in 6 hours of storage, but increased gradually thereafter. VBN contents in the muscles continuously increased throughout the storage of fish. Slightly higher levels of APC and VBN were observed in the tested fish than control fish, which had been exposed to air until died and stored in seawater without treating C. polykrikoides. After 12 hours of storage, APC and VBN contents in the muscles did not exceed the initial spoilage limit, 10$^{5}$ CFU/g fur APC and 30 mg/100 g for VBN, in all of the fish including control fish. Organoleptic change in fish treated with C. polykrikoides did not greatly differ from the control fish. After 8 hours of storage, distinctive deterioration of muscle was detected organoleptically in the treated fish and the control fish. The compiled result indicated that moribund fish exposed to C. polykrikoides bloom should be handled properly in 6 hours of storage after death of fish.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.760-763
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• 2001

Five commercial salt-fermented shrimps contained 29.8~48.3% of salt 3.5%~7.3% of total nitrogen and 0.3~0.7g/100g of amino-nitrogen respectively. The average peptide length(APL) of five commercial salt-fermented shrimps ranged from 10.1 to 15.0. Sample B and E showed longer APL than the others with the values of 15.0 and 14.4 respectively. Protease activity showed the large differences in five samples from 17 unit to 232 unit ; sample C showed the highest protease activity with 232 unit while sample D and E were relatively lower with 17 unit and 18 unit respectively. The chitinase activities which can hydrolyze chitin the one of components on outer layer of shrimp ranged from 14.4 unit to 171 unit. Sample E had the highest chitinase activity as 171 unit but sample B showed the lowest activity with 14.4 unit. Chitooligosaccharides of five commercial salted-fermented shrimps were consisted of monoglucosamine diglucosamine and triglucosamine.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.3
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• pp.145-151
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• 2023

In order to extend shelf life for rockfish fillets by modified atmosphere packaging (MAP), different package atmospheres were compared in the product quality preservation. Firstly, CO₂ solubility was measured at 0, 5, 10, and 15℃ to be incorporated into the mathematical model to predict the volume and CO₂ concentration of the package at expected storage temperature. The CO₂ solubility given in Henry's constant decreased with temperature to be fitted with a linear equation. Then air packaging as control and four MAP conditions of 100 g fillets were prepared and stored for duration of 5 days at 10℃ to compare them in the quality preservation effect. Four MAP conditions employed were CO₂(60):O₂(30):N₂(10), CO₂(60):O₂(0):N₂(40), CO₂(30):O₂(30):N₂(40) andCO₂(30):O₂(0):N₂(70). MAP conditions with high CO₂ concentration inhibited total aerobic bacteria, and the conditions containing O₂ led to low TVB-N. MAP of CO₂(60):O₂(30):N₂(10) was found to be the best condition for rockfish fillet preservation considering total aerobic bacteria growth and nitrogenous volatiles production.

• 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.

• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.185-192
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• 1995

Microbial and chemical changes of salt-fermented youbsak which is a traditional processed fish product only manufactured in Hampyung bay region were investigated in this study. Total microbial cells of salt-fermented youbsak was gradually increased up to 30 days fermentation and then it was decreased. The pH and total acidities of fermented youbsak were not greatly changed, except for a rapid decrease in pH and acidity after 15 days fermentation. Volatile basic nitrogen and amino-type nitrogen were rapidly increased until 30 days fermentation and then slightly decreased by adding the extracted soup of pig bones. Palmitic acid was the most abundant fatty acid, and the major free amino acids in salt-fermented youbsak were composed of leucine, tyrosine, glutamic acid, valine, isoleucine, alanine and methionine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.965-967
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• 2000

An on-line FIA system in place of traditional Conway method was used for quicker and simpler analysis of volatile basic nitrogen of pork. The on-line system was developed by connecting an FIA apparatus with an ammonia electrode as a detector to a personal computer. The data from Conway method and from the on-line FIA system were in good agreement and the correlation coefficient was 0.981. One sample could be analyzed in about 4 min.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.20-25
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• 2000

This study was conducted to evaluate the quality of the plain dried anchovies on the market by determining chemical components, and compared with those of boiled-dried anchovy. The nutritional(total amino acid contents, mineral contents and fatty acid compositions) and favorite properteis (extratives nitrogen content, color and appearance) of plain dried anchovies were superior to those of boiled-dried anchovy. On the other hand, the lipid properties (peroxide value and acid value), food sanitary properteis (volatile basic nitrogen content) and sensory properties (odor) of plain dried anchovies were inferior to boiled-dried anchovy. These results indicated that the plain dried anchovy was classified into lower grade goods by food quality standards.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1049-1055
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• 2004

The effects of ethanol extract of onion (EEO) on the qualify of fried fish paste were investigated. EEO was added at 0, 1, 3 and 5% level. Quality attributes including moisture content, pH, acid value, TBA value, volatile basic nitrogen, color value, viable cell count and sensory evaluation were analyzed. Moisture content was not changed by addition of EEO. Increasing the amount of EEO, pH, acid value and TBA value of fried fish paste tended to decreased but volatile basic nitrogen increased. L-value was decreased and a-value and b-value were increased by addition of EEO. Viable cell count was decreased by addition of EEO. In sensory evaluation, the higher amount of EEO obtained higher favorite score in flavor and taste, and 3% EEO had the best score in overall acceptance. These results suggest that EEO can be applied to fried fish paste for the purpose of high quality and functionality.