• Journal of Microbiology and Biotechnology
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• v.13 no.5
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• pp.692-699
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• 2003

The changes of physicochemical and microbiological states of Myeolchi-jeot, a Korean salted and fermented anchovy, were investigated during 20 days of storage at $4^{\circ}C,\;15^{\circ}C,\;and\;30^{\circ}C$. A total of 314 bacterial strains isolated from Myeolchi-jeot samples at different time intervals were identified, and their abilities to produce biogenic amines were determined by both decarboxylating agar media and HPLC analysis. The salinity and water activity of Myeolchi-jeot changed little, while the pH increased slightly over 20 days at the tested temperatures. A significant increase of total plate count was observed in the sample stored at $30^{\circ}C$. Staphylococcus spp. were dominant in Myeolchi-jeot, and its amine productivity was very weak. Bacillus spp. appeared increasingly with the progress of storage at all temperatures tested, and the increase was considerably dependent on the increase of storage temperature. Also, 58-73%, 83-90%, 81-90%, and 83-93% of Bacillus strains had the ability to produce histamine, tyramine, putrescine, and cadaverine, respectively. Therefore, the main amine producer in Myeolchi-jeot stored for a long period seems to be the genus Bacillus, especially B. licheniformis.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.168-170
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• 2005

The myeolchi-jeot samples were divided into different groups with or without the supplementation with biogenic amines. Subsequently, the samples were placed in an oven at $80^{\circ}C$ for 1 hr to allow the chemical reaction to proceed, and then were analyzed for N-nitrosamine contents using GC-TEA. N-nitrosamine was not detected in any of the myeolchi-jeot samples which had been treated with/without sodium nitrite. On the other hand, the yield of N-nitrosopyrrolidine from 1,000 mg/kg of putrescine and spermidine in the myeolchi-jeot samples (treated with 5 mg/kg of sodium nitrite) was 0.002 and 0.014%, respectively. N-nitrosamine was not produced from any other biogenic amines like, histamine, tyramine, cadaverine and spermine. In addition, curing and heating were the factors which influenced the formation of N-nitrosamine during the nitrosation of biogenic polyamines. For the formation of N-nitrosamine in the food systems, treatment with sodium nitrite and heating at appropriate temperature along with the satisfied supplementation of biogenic polyamines are required.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1341-1349
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• 2000

The addition of 5% NaCI to standard plate count (SPC) and bromcresol purple (BCP) agar showed the highest viable cell counts for Jeot-kal samples. The use of 15% glycerol as cryoprotectant showed the highest microbial survival rate at both temperatures, $-20^{\circ}C$ and $-170^{\circ}C$, and on both colony count media, SPC and BCP. During the aging, the pH of Bajirak Jogae-Jeot (fermented clam) decreased from 6.8 to 5.0. Crude protein content was 10% for Bajirak Jogae-Jeot and $6{\sim}7%$ for Myeolchi-Jeot (fermented anchovy). Microbial population of Bajirak Jogae-Jeot was $10^9\;CFU/g$ after 4 weeks of aging, but was only $10^{3-5}\;CFU/g$ in the case of Myeolchi-Jeot. The proportion of Gram positive and catalase negative bacteria in Bajirak Jogae-Jeot increased drastically during the 4 weeks of aging, which showed typical lactic bacterial fermentation. After 2 years' storage of Jeot-kal in liquid nitrogen tank, the cell counts of total aerobic or lactic bacteria were decreased, resulting in about 10% survival rate. Microbial floral change of Jeot-kal was also investigated. In the case of Bajirak Jogae-jeot, the ratio of rod to cocci and that of Gram negative to positive increased after liquid nitrogen storage. But, rod to cocci ratio of Myeolchi-jeot decreased after liquid nitrogen storage. The ratio of yeasts decreased in both cases after storage.

• Korean journal of food and cookery science
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• v.9 no.3
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• pp.222-229
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• 1993

The purpose of this study was investigated kinds and utilities of Jeot-kal(fermented fish products) in 55 different regional area which were classified three temperature zone. The result were as follows ; (1) 95 kinds of jeot-kal found, they were subdivided 4 groups according to types and part of fish used : whole fish(46 kinds), vicera(11 kinds), shellfish(14 kinds), mollusca(4 kinds) and crustaceans(20 kinds). 17 kinds of jeot-kal were found in all area. (2) They were used as side dish, seasoning substitution of soy sauce or vinegar and important materials of kimchi. In Kimchi, 49 kinds of jeot-kal were used and Myeolchi Jeot(self-fermented enchovy) was prefered at southern area, saewoo jeot (self-fermented small shrimp), gonjengi jeot(self-fermented Mysis), hwangsegi jeot(self-fermented Hwangandali) were prefered at nouthern and middle area. Sometimes they were used in sacrified service. (3) Salt content and pH of jeot-kal at southern area were higher than other area.

• Proceedings of the Korean Nutrition Society Conference
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• 2003.05a
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• pp.227.1-227.1
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• 2003

• Fisheries and Aquatic Sciences
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• v.19 no.10
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• pp.42.1-42.10
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• 2016

The objectives of this study were to identify the histamine-forming bacteria and bacteriocin- producing lactic acid bacteria (LAB) isolated from Myeolchi-jeot according to sequence analysis of the 16S rRNA gene, to evaluate the inhibitory effects of the bacteriocin on the growth and histamine accumulation of histamine-forming bacteria, and to assess the physico-chemical properties of the bacteriocin. Based on 16S rRNA gene sequences, histamine-forming bacteria were identified as Bacillus licheniformis MCH01, Serratia marcescens MCH02, Staphylococcus xylosus MCH03, Aeromonas hydrophila MCH04, and Morganella morganii MCH05. The five LAB strains identified as Pediococcus acidilactici MCL11, Leuconostoc mesenteroides MCL12, Enterococcus faecium MCL13, Lactobacillus sakei MCL14, and Lactobacillus acidophilus MCL15 were found to produce an antibacterial compound with inhibitory activity against the tested histamine-producing bacteria. The inhibitory activity of these bacteriocins obtained from the five LAB remained stable after incubation at pH 4.0-8.0 and heating for 10 min at $80^{\circ}C$; however, the bacteriocin activity was destroyed after treatment with papain, pepsin, proteinase K, ${\alpha}$-chymotrypsin, or trypsin. Meanwhile, these bacteriocins produced by the tested LAB strains also exhibited histamine-degradation ability. Therefore, these antimicrobial substances may play a role in inhibiting histamine formation in the fermented fish products and preventing seafood-related food-borne disease caused by bacterially generated histamine.

• Journal of the Korean Society of Food Culture
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• v.25 no.3
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• pp.241-250
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• 2010

This study was conducted to improve the kimchi intake for high school students of various kimchi sub-ingredients and foods using kimchi. The students believed that kimchi is good for health. The overall satisfaction, baechu quality and the taste and degree of fermentation of kimchi was high, but there was a low preference for offered kimchi kinds, kimchi subingredient, foods using kimchi. The types of kimchi preferred and often offered in school meals were baechu-kimchi and kkakdugi. The common kimchi sub-ingredients were radish and welsh onion in vegetables, squid and oyster in sea foods, saeu-jeot and myeolchi-jeot in salted fish, and pear and apple in fruits. The preference for kimchi sub-ingredients were high for sesame leaf and yeolmu in vegetables, saeu-sal and squid in sea foods, saeu-jeot and nakji-jeot in salted fish, and pear and apple in fruits. The foods using kimchi preferred and often offered with school meals were kimchi-jjigae, bokkeumkimchi, kimchi soup, kimchi-bokkeum-bap, and kimchi-jeon. The kimchi sub-ingredient for which students had the greatest preference was meats. Among the foods using kimchi with meats, the most preferred were kimchi-pyeonyuk bossam, doejigogi kimchi duruchigi, and kimchi galbi-jjim. Among the foods using kimchi with noodles, the most preferred were kimchi- bibimmyeon, kimchi -naengmyeon, and kimchi-cheese spaghetti. Among the foods using kimchi with vegetables, the most preferred were kimchi-pa-jeon, kimchi- deopbap and kimchi- goguma gui. Of the foods using kimchi with processed foods, the most preferred were kimchi-mandu, kimchi-bacon jumeok-bap and kimchi- cheese omelet. Among the foods using kimchi containing sea food, kimchi-haemul bokkeum-bap, kimchi-hoe-deopbap, and kimchi-saeu-jjim were most preferred. Overall, these results suggest that various kimchi sub-ingredients and foods using kimchi should be improved for kimchi intake of school meals.

• Journal of Applied Biological Chemistry
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• v.63 no.4
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• pp.375-385
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• 2020

The purpose of this study was to investigate the quality characteristics of kimchi prepared with a single starter culture of biogenic amines (BA)-forming lactic acid bacteria (LAB) or a combined starter cultures composed of BA-forming and BA-degrading LAB. As the fermentation proceeded, the lactic acid bacterial count, titratable acidity, and BA content in kimchi prepared with myeolchi-aekjeot were slightly higher than those of kimchi prepared with saeu-jeot. The amount and type of BA produced by LAB were mostly strain dependent rather than species specific. Among all of the isolated LAB strains, the highest levels of cadaverine, histamine, putrescine and tyramine were produced by Leuconostoc mesenteroides MBK32, Lactobacillus brevis MBK34, Lactobacillus curvatus MBK31 and Enterococcus faecalis SBK31, respectively. BA-forming and BA-degrading starter cultures played an important role in the growth rate and organic acid-producing ability of LAB in kimchi. Interestingly, BA contents in kimchi increased by adding single BA-forming LAB starter were effectively lowered by the mixed cultures with BA-degrading LAB.