• 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 Fisheries and Aquatic Sciences
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• v.14 no.2
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• pp.66-71
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• 1981

In order to study the decomposition process of glycogen and protein of oyster during fermentation with salt, and the relationship between their breakdown products, the amounts of free reducing sugars and lactic acid were determined, and amino acid compositions were analysed. In addition, the amount of the available lysine which may help us to estimate the reaction of the free reducing sugars with the free amino acids was also determined. Glycogen and protein were gradually decomposed to free reducing sugars and lactic acid, and free amino acids, respectively, and the available lysine was slightly decreased during the fermentation process. Glutamic acid, aspartic acid, lysine and proline were relatively rich in the amino acid com-position of raw oyster protein while amino acids such as tryptophan, methionine, histidine and tyrosine were poor. It was noted that the decreased amino acids in the protein from the fermented oyster were valine, histine, isoleucine and lysine. As a respect to the free amino acids, proline, taurine, glycine, glutamic acid and alanine were abundant in the raw oyster and reached up to $69\%$ of the total fret amino acids. In the fermented oyster, proline, glutamic acid, glycine, alanine, aspartic acid and lysine were prevalently contained and marke about $65\%$ of the total free amino acids. The contents of free amino acids such as lysine, arginine, aspartic acid, glutamic acid, cysteine, isoleucine and tyrosine increased during fermentation while those of taurine, proline and leucine decreased.

• Korean Journal of Agricultural Science
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• v.35 no.2
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• pp.155-165
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• 2008

A seasoned squid Jeotkal, Korean traditional fermented seafood, and its ingredients for manufacturing, including red hot pepper powder, ground garlic, sesame seeds, were irradiated with 0, 0.5, 1, 2, and 5 kGy by electron beam and stored at $4^{\circ}C$ for 4 weeks to determine the changes in microbiological and sensory characteristics. The initial contamination of squid Jeotkal such as total aerobic bacteria, yeast & mold, and coliform bacteria were at the levels of 2.88, 3.04, and 4.20 log CFU/g, respectively. However, electron beam irradiation with does at 5 kGy reduced the total aerobic bacteria to about 1 log CFU/g. Yeast & mold and coliform bacteria were reduced to 1-2 log CFU/g after 2 kGy of irradiation and reached to undetected level when the sample was irradiated at 5 kGy and following storage at $4^{\circ}C$ for 4 weeks. Sensory characteristics showed that electron beam irradiation of up to 5 kGy did not adversely affect overall acceptability of squid Jeotkal and its ingredients during cold storage. Therefore, electron beam irradiation is one of the possible means to improve storage stability of seasoned squid jeotkal, which has limited alternative sterilization methods due to the temperature characteristics of the products.

• Food Engineering Progress
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• v.15 no.2
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• pp.122-129
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• 2011

In this study, discrimination of salted cuttle fish and salted mitra squid was carried out using electronic nose based on mass spectrometer. Intensities of each fragment from salted cuttlefish by electronic nose were completely different from those of salted mitra squid. Each sample was analyzed, and discriminant function analysis (DFA) was used for the discrimination of similar products. DFA plot indicated a significant separation of each salted cuttlefish and mitra squid ($r^2$= 0.8789, F= 162.13). Electronic nose based on mass spectrometer could be used as an efficient method for discrimination of Economically Motivated Authentication (EMA) foods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.16-19
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• 2000

The ATP related compounds play an important role in a taste of traditional salt-fermented seafoods (Jeotkals). The ATP related compounds were analyzed in the traditional anchovy Jeotkal during fermentation and 11 kinds of commercial Jeotkals by enzymatic method compared with existing HPLC method, In the traditional anchovy Jeotkal, the contents of $ATP{\~}IMP$ decreased during fermentation, while the contents of Hx reached maximum value at 60 days fermentation and thereafter decreased gradually. Uric acid was detected at 30 days fermentation and showed the gentle increment after that. In the commercial Jeotkals, uric acid was detected $14.6{\~}28.4{\%}$ of total ATP related compounds content by enzymatic method, while it was not detected by HPLC method. From these results, enzymatic method is more accurate than HPLC method for analysis of the ATP related compounds in Jeokals.

• Korean Journal of Microbiology
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• v.45 no.1
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• pp.26-31
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• 2009

This study was aimed at the analysis of prokaryote communities in Korean traditional fermented food, jeotgal, and isolation of a novel strain from jeotgal by using culture-dependent and molecular biological approaches. Seventeen kinds of jeotgal were selected on the basis of its origins and sources. The samples were inoculated on 12 kinds of media. 308 isolates were selected randomly by morphological features, and its 16S rRNA gene sequences was amplified by PCR technique with bacteria and archaea specific primers (8F, 21F, and 1492R). The 16S rRNA gene sequences were compared with those in EzTaxon and GenBank databases. DNA-DNA hybridization was performed to identify a novel strain. As a result, the majority of the isolates were lactic acid bacteria (Leuconostoc, Weisella, Lactococcus, Lactobacillus, Carnobacterium, Marinilactibacillus), Bacillus, Pseudomonas, Micrococcus, Brevibacterium, Microbacterium and Kocuria in 17 kinds of jeotgal. The strains belonging to Salinicoccus, Halomonas, Cobetia, Lentibacillus, Paracoccus, and Psychrobacter were isolated as minor ones. Fourteen novel species were identified based on phylogenetic analysis.

• Korean journal of food and cookery science
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• v.21 no.4 s.88
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• pp.440-446
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• 2005

To determine the shelf-life of low salted Myungran-jeot (low salted and fermented Alaska pollack roe), various chemical, microbiological and sensory analyses were carried out with Myungran-jeot stored at 10 days. The lactic acid content was slowly increased in the early stage of storage but then was rapidly increased with lengthening storage period, while pH was decreased during storage. The $NH_2-N$ content was steady at 10 days and peaked at 17 days. The production of VBN was increased to over $30mg\%$ at 19 days. In microbiological tests, the viable cell count and halotolerant bacteria were $1.5\times10^3\;and\;5.5\times10^3CFU/g$, respectively, at the initial state, but they slowly increased to $10^7 CFU/g$ at 17 days. Yeast or fungi did not appear on the surface of Myungran-jeot. Sensory evaluation showed that the original torture of Myungran-jeot in the mouth was a very important indicator for acceptability. Sensory characters and acceptability of Myungran-jeot at 17 days were not significantly different from those of the initial state. From these results, the estimated shelf-life of Myungran-jeot whom sealed with aluminum coated paper, was about 18 days in this study.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.355-362
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• 2017

Fermentation temperature (10 and $20^{\circ}C$) and salt concentration (10, 20, and 30%) on volatile basic nitrogen (VBN), histamine, amino nitrogen, total viable cell counts, coliform bacteria and Escherichia coli counts as the quality index in salted shrimp were investigated during fermentation. Results show that the effect of salt concentration on changes in quality index was not high compared with fermentation temperature (10 and $20^{\circ}C$) in salted shrimp treated with 10% and 20% salt concentration. However, effect of salt concentration and fermentation temperature on the quality index was not significant with 30% salt concentration. And all most whole changes of quality index were rapidly increased or decreased for 30 days of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.348-352
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• 1994

The adding effect of Koji, made by Aspergillus oryzae, in low salt-fermented anchovy paste was studied to reduced fermentation time and to enhance flavor quality as a commercial feasibility in seafood industry. The content of volatile basic nitrogen increased slowly during fermentation , whereas that of amino nitrogen was the highest in 30 days of low salt-fermented anchovy made with Koji. Protease and lipase activity in anchovy paste, which made with or without Koji, were high amount in 30 and 20 days of fermentation, respectively. A number of proteolytic bacteria was high level in 13 days and then slowly decreased afterward.

• 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.