• Journal of Microbiology and Biotechnology
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• v.24 no.5
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• pp.648-660
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• 2014

Doenjang, a traditional Korean fermented soybean paste, is made by mixing and ripening meju with high salt brine (approximately 18%). Meju is a naturally fermented soybean block prepared by soaking, steaming, and molding soybean. To understand living bacterial community migration and the roles of bacteria in the manufacturing process of doenjang, the diversity of culturable bacteria in meju and doenjang was examined using media supplemented with NaCl, and some physiological activities of predominant isolates were determined. Bacilli were the major bacteria involved throughout the entire manufacturing process from meju to doenjang; some of these bacteria might be present as spores during the doenjang ripening process. Bacillus siamensis was the most populous species of the genus, and Bacillus licheniformis exhibited sufficient salt tolerance to maintain its growth during doenjang ripening. Enterococcus faecalis and Enterococcus faecium, the major lactic acid bacteria (LAB) identified in this study, did not continue to grow under high NaCl conditions in doenjang. Enterococci and certain species of coagulase-negative staphylococci (CNS) were the predominant acid-producing bacteria in meju fermentation, whereas Tetragenococcus halophilus and CNS were the major acid-producing bacteria in doenjang fermentation. We conclude that bacilli, LAB, and CNS may be the major bacterial groups involved in meju fermentation and that these bacterial communities undergo a shift toward salt-tolerant bacilli, CNS, and T. halophilus during the doenjang fermentation process.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.919-924
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• 2008

The aim of this study was to observe the changes in allergenicity of saeujeot (salted and fermented shrimp) using a competitive indirect enzyme-linked immunosorbent assay (Ci-ELISA). The fermentation conditions tested for saeujeot consisted of various temperatures (25, 15, and $5^{\circ}C$) and salt concentrations (25, 15, and 10%). When saeujeot was fermented at a low salt concentration and high temperature, the binding ability of mAb and shrimp-allergic patient serum to allergen was significantly decreased. In particular, the binding ability of mAb to allergen in saeujeot fermented with 10% salt at $25^{\circ}C$ for 5 days decreased to 5%. Also, the binding ability of shrimp-allergic patient serum to allergen in saeujeot fermented for 5 days with 10% salt at $25^{\circ}C$ was 8%. In conclusion, the binding of mAb and shrimp-allergic patient serum to tropomyosin in saeujeot decreased with longer fermentation periods, lower salt concentrations (10%), and higher temperatures ($25^{\circ}C$).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.195-201
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• 1998

Anchor Engraulis japonica was fermented with $10\%$ and $20\%$ salt at $10^{\circ}C$ ($10\%$ 5A) and $20^{\circ}C$ ($20\%$ SA), respectively, and the changes in lipid content, fatty acid composition and lipid oxidation was observed for 105 days. Peroxide value (POV) in $10\%$ SA reached to the maximum (46.4 meq/kg) on 30 days of fermentation, while in $20\%$ SA, it reached the maximum (54.7 meq/kg) on 45 days of fermentation, and then decreased in both samples during fermentation. Thiobarbituric acid values revealed a similar tendency with the change of POV during the fermentation. These results indicated that lipid of the anchovy was oxidized faster in lower salt than high salt in the early stage. Total lipid (TL) content during the fermentation for 105 days decreased approximately $16\%$ in $10\%$ SA and approximately $33\%$ in $20\%$ SA. Phospholipid (PL) content also decreased in both samples and the content of neutral lipid (NL) was unchanged in $10\%$ SA, while it decreased in the same amount as PL in $20\%$ SA. The prominent fatty acids in TL of the anchovy sample were 14 : 0, 16 : 0, 16 : In-7, 18 : in-9, 20 5n-3 and 22 : 6n-3. After fermentation for 105 days, approximately $87\%$ and $67\%$ of the prominent fatty acids remained in $10\%$ SA and $20\%$ SA, respectively, but the kind of the fatty acids was unchanged.

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.296-301
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• 1999

A Bacillus strain from Korean soil was isolated and identified to be Bacillus licheniformis B1 through various biochemical tests, VITEK, and MIDI system analysis. The strain produced extracellular amylase and protease. Whether or not the strain can perform Chungkookjang fermentation with autoclaved soybean and Kanjang fermentation was determined in this study. In Chungkookjang fermentation, browining materials of strong anti-oxidant increased 8-fold, and 2-fold in Kanjang, compared with initiation material for fermentation. Maximal protease activity in Chungkookjang was observed one day after inoculation. Protease activities in Kanjang decreased to the half, and then maintained constant values during fermentation, probably due to the inhibitory effect of salt on protease activities. High molecular mass of nucleic acids was identified in Chungkookjang and Kanjang. Since the nucleic acids were not observed in autoclaved soybean, they seem to be originated from B. licheniformis B1. This study demonstrated successive fermentation of Chungkookjang and Kanjang by B. licheniformis B1 isolated from nature, and suggested possible development of food rich in browing and nucleic acids.

• 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.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.592-599
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• 2012

The effect of additives on the quality of low-salt doenjang was investigated. The amylase activity of the mustard added group decreased during the fermentation period, and the number of yeast and bacteria was also decreased during the fermentation period. The oxidation-reduction potential was low at the later fermentation stages for the mustard and mustard-garlic added groups, and water activity decreased considerably for the alcohol added group. The L-value of alcohol added doenjang decreased with increases in the a-value. The pH was 4.84 in the mustard added group. The reducing sugar content was 10.15% in the alcohol-garlic added group, and the alcohol production was limited by adding mustard. The amino-type and ammonia-type nitrogen were high in garlic and mustard added groups. Alcohol and alcoholgarlic added groups exhibited significantly improved taste and overall acceptability of doenjang.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.421-426
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• 1999

This study was conducted to examine the quality of low-salt Mul-kimchi which was prepared by mixing of radish (25%), green onion (2.4%), red pepper (1.9%), garlic (1.9%) and salt (0, 0.2, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0%) in water and followed by fermentation at 4, 15 and $25^{\circ}C$ for 10 days, respectively. The pH was lowest and acidity was highest in the Mul-kimchi containing 1.0% salt. The total vitamin C contents in Mul-kimchi containing $0{\sim}0.2%$ salt were high at the early stage of fermentation while those of Mul-kimchi containing 3.0% salt were higher than the low-salt samples after the optimal ripening time. The hardness of the radish increased with the salt concentration. Overall palatability of Mul-kimchi showed the highest score in 1.0% salt sample.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1107-1113
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• 2000

Gamma irradiation technology was applied to develop salted and fermented shrimp with lower salt concentration, high sensory quality and storage stability. Shrimp was prepared with 15 and 20% of salt and fermented at $15^{\circ}C$ for 10 weeks. The sample was irradiated at 0, 5.0 and 10.0 kGy right before optimum stage of fermentation. Fermented shrimp with 30% of salt concentration was also prepared as a control. The proximate composition, salinity and Aw were not affected by gamma irradiation. However, pH of irradiated samples was lower than that of non-irradiated samples, probably because irradiation effectively suppressed excessive fermentation by controlling microorganisms. From the results of sensory analysis, it was concluded that fermented shrimp with 15% of salt and irradiated at 10 kGy before optimum fermentation, or 20% of salt and 5 kGy or above were the most effective in terms of sensory quality and storage stability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.3
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• pp.460-469
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• 1996

This study was intended to observe the physicochemical and sensory characteristics of anchovy added kimchi during fermentation at 4$^{\circ}C$ for 4 weeks. Salting of Chinese cabbage for 10 hours at 10% brine solution was turned out to be appropriate organoleptically for kimchi preparation. Salt content of all kimchies prepared in this study was below 2%. The changes of pH and acidity during fermentation was slow in raw anchovy added kimchi compared to other kimchies. The content of vitamin C was not changed significantly through the fermentation period, whereas the content of reducing sugar was increased at the early stage of fermentation and subsequently decreased as fermentation proceeded. The number of lactic acid bacteria was the highest in raw anchovy added kimchi. The content of calcium and phosphorus were higher in anchovy powder added kimchi and raw anchovy added kimchi than control. In the early stage of fermentation, the major pigments of kimchi were the chlorophyll and carotenoid, but in the later stage of fermentation, the color of Chinese cabbage became greenish brown as chlorophyll was converted to pheophytin. In sensory evaluation test, raw anchovy added kimchi received high score at the early stage of fermentation and anchovy powder added kimchi at the late stage of fermentation, respectively.

• Journal of the Korean Applied Science and Technology
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• v.30 no.2
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• pp.348-355
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• 2013

Squid ink was added to the salt fermented squid by 2% or 4% of concentration and ripened at $10^{\circ}C$ for 8 weeks and at $20^{\circ}C$ for 32days. The effects of the squid ink on the amino nitrogen and muscle protein of salt fermented squid were investigated. The results are as follows; As the salt concentration was decreased and the fermentation temperature raised, amino nitrogen in the salt fermented squid without addition of the squid ink was significantly increased to the latter stage of the ripening and hence fermentations were enhanced. From the change of the protein in the squid muscle in the experiments, dissolution of the myosin heavy chain took place conspicuously in the early stage of the ripening while actin was rarely changed which resulted in the strong resistance to protease. The amino nitrogen content in the salt fermented squid addition of the squid ink has increased to the latter part of the ripening but the range was smaller than no treatment groups. The protein in squid muscle, especially the myosin heavy chain was remarkably dissolved in the middle of the ripening whereas the squid ink added groups of high salt concentration and low temperature showed the tendency of slow proteolysis.