• 동아시아식생활학회지
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• 제19권3호
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• pp.395-400
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• 2009

This study was performed to examine the effects of salt addition levels on changes in the physicochemical properties of salted and fermented shrimp for HACCP determination. The salted shrimp were prepared from fresh shrimp using different concentrations (8, 18, 28%) of chunil salt, and were then fermented at $10^{\circ}C$ for 160 days. Amino nitrogen, VBN and TMA contents rapidly increased in the 8% group during the fermentation period, while the 18% and 28% groups maintained their initial levels throughout the 160 day fermentation period. The thiobabituric acid (TBA) values of the groups increased rapidly over 120 days of fermentation, and then decreased thereafter. The TBA values of the 18% and 28% groups were lower than that of the 8% group. The peroxide values of the 18 and 28% groups rapidly increased over 30 days of fermentation, whereas the values for the 8% group, rapidly increased with 60 days of fermentation.

• 한국미생물·생명공학회지
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• 제27권3호
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• pp.246-251
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• 1999

To extend the storage period and to inhibit contamination of Kimchi by Escherichia coli, conditions of Kimchi brining and effects of the fermentation starter, halophilic Lactobacillus HL-48 were investigated. Optimum brining condition for Kimchi was accomplished in 15% NaCl and at pH2.5-3.0 adjusted by lactic acid. Starter-treated Kimchi showed pH 4.2 after 18hr fermentation, while the pH of starter-untreated Kimchi resulted in 3.3. After 36hr fermentation, the number of E. coli in starter-treated Kimchi was found clearly to decrease and not detected macroscopically, but contamination of E. coli (5.3$\times$103CFU/ml) was observed in starter-untreated sample. Organic acids in Kimchi contained organic acids such as oxalic acid, citric acid, malic acid and lactic acid. among ther, lactic acid content was remarkably high in the early fermentation stages. However, from 24hr fermentation, lactic acid content of starter-untreated Kimchi was higher than that of starter-treated Kimchi.

• 한국식품영양과학회지
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• 제24권5호
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• pp.752-757
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• 1995

발효숙성 온도를 달리한 돌산 갓 김치의 저장 중 pH, 산도, 염도, 색도, 비타민 C 등의 이화학적 특성을 알아 보았다. 발효숙성 방법으로는 $4^{\circ}C(A),\;20^{\circ}C(B),\;20^{\circ}C$에서 12시간 숙성시킨 후 $4^{\circ}C$에 저장하는 방법(C), $20^{\circ}C$에서 36시간 숙성시킨 후 $4^{\circ}C$에 저장하는 방법(D)으로 하였다. 돌산 갓 김치 담금 직후의 pH는 5.24이었고, $20^{\circ}C$에서 12시간과 36시간 숙성시킨 후 $4^{\circ}C$에 저장된 C, D군에서 각각 pH 5.13, pH 5.10으로 A군 보다 모두 낮았으며 B군에서는 급속하게 변화하였다. 갓 김치의 적숙기라 할 수 있는 pH 4.6~4.8이 되는 시기는 A군이발효 78~96일, B군은 6~9일, 그리고 C, D군은 모두 68~88일로 같게 나타났다. 총산 함량에 있어서는 담금 직후 0.5%이었고, C, D군은 모두 0.6%으로 A군의 0.5%보다 모두 높게 나타났다. 또한 pH 4.6~4.8이 되는 시기의 총산 함량에 있어서 A군은 0.75~0.82%, B군은 0.65~0.70%, C군은 0.80~0.81%, D군 0.82~0.84%이었다. 갓 김치의 염도는 $20^{\circ}C$인 B군에서 증가폭이 컸고, 다음으로 D > A > C 순으로 나타났다. 도는 발효가 진행됨에 따라 L, a값은 증가했다가 다시 감소하였고 b값은 증가하였다. 특히 B군에서 L값이 적숙기에 증가하여 밝아지는 현상을 나타내었으나, 최종 김치의 색은 C > D > A > B 순으로 좋게 나타났다. 발효숙성일수가 경과함에 따라 총 비타민 C 함량은 9.0~14.0mg%까지 감소하였으며 적숙기에 가서 22.0mg%로 다소 증가 하다가 후기에 서서히 감소하였다. A군은 완만한 감소(25~22 %)를 보인 반면 B군은 다소 감소폭(25~7.0mg%)이 컸다. 발효 후기의 총 비타민 C 보유량에는 A > D > C > B 순으로 높게 나타났다.

• 한국식품영양과학회지
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• 제43권7호
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• pp.1081-1087
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• 2014

김치를 절임 배추와 양념소로 각각 분리하여 발효하였을 때와 포기김치의 형태로 함께 발효하였을 때 그 품질특성이 어떻게 변화하는지를 $4^{\circ}C$에서 4주간 발효하면서 관찰하였다. 절임 배추, 양념소와 포기김치의 이화학적 특성으로는 pH, 산도, 총균 및 유산균의 수, 배추 조직의 탄력성 평가를 실시하였다. $4^{\circ}C$에서 4주간 저장한 양념소는 pH, 산도의 변화와 미생물수의 변화로 미루어 볼 때 절임 배추나 포기김치보다 발효가 더디게 진행되는 것을 알 수 있었다. $4^{\circ}C$에서 4주간 분리하여 저장한 절임 배추의 경우는 양념소에 비해 빠르게 발효가 진행되는 것을 알 수 있었으며 이것은 포기김치의 발효 양상과 거의 비슷한 경향을 보였다. 이로써 김치의 발효는 양념소에 의한 것보다는 배추에서 유래되는 영향이 더 큰 것으로 생각된다. 또한 포기김치의 형태로 저장한 이후 실험 직전에 절임 배추와 양념소를 따로 분리하여 그 발효 양상을 관찰하였다. 포기김치로부터 분리해낸 절임 배추와 양념소의 pH, 산도, 미생물수는 4주간 따로 저장한 절임 배추, 양념소와 비슷한 경향을 나타내어 따로 혹은 함께 발효를 진행하여도 그 발효 양상이 비슷함을 알 수 있었다. 또한 김치와 절임 배추 조직의 탄력성을 측정한 결과 4주간의 발효기간 동안 유의적인 차이를 보이지 않는 것으로 나타났다. 이를 바탕으로 김치의 발효는 양념소보다는 절임 배추에 의해 보다 큰 영향을 받는 것으로 생각된다.

• 한국식생활문화학회지
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• 제36권3호
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• pp.265-273
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• 2021

The Chinese Sigyeong records the foods of the Primitive Pickling Period, pickling being a universal vegetable storage method, but does not indicate the origin of the pickled vegetables or the location of the source of transmission. Kimchi mainly used salt and sauce-based soaking materials at the beginning of the Fermented Pickling Period (beginning in the 1st to 3rd centuries A.D.), and it differed from the Chinese method, which used alcohol and vinegar. In the Umami-Flavored Pickling Period (beginning in the 14th and 15th centuries A.D.), jeotgal, fermented seafoods, were added, and pickles with a completely new identity were created, one different from any other pickles in the world. Lastly, entering the Complex Fermentation and Pickling Period (beginning in the 17th and 18th centuries), the technical process evolved using a separate special seasoning containing red pepper as the secondary immersion source after pickling in brine, the primary immersion source. As a result of this, kimchi was transformed into a food with a unique form and taste not found anywhere else. The unique characteristic of kimchi is that the composition of original materials, a combination of salted marine life and vegetable ingredients, is its core identity, and there is a methodological difference in that it is completed through a second process called saesaengchae (生菜)-chimchae (沈菜).

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.422-427
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• 2003

Rhodopseudomonas palustris P4 can produce $H_2$ either from CO by water-gas shift reaction or from various sugars by anaerobic fermentation. Fermentative $H_2$ production by P4 is fast, but its yield is relatively low due to the formation of various organic acids. In order to increase $H_2$ production yield from glucose, P4 was investigated for the photo-fermentation of acetate which is a major by-product of fermentative $H_2$ production. Experiments were performed in batch modes using both light-grown and dark-grown cells. When the dark-grown P4 was challenged with light and acetate, $H_2$ was produced with the consumption of acetate after a lag period of 25 h. $H_2$ production was inhibited when a nitrogen source, especially ammonium, is present. When the dark-fermentation broth containing acetate was adopted for photo-fermentation with light-grown cells, $H_2$ production and concomitant acetate consumption occurred without a lag period. The $H_2$ yield was estimated as 2.4 - 2.8 mol $H_2/mol$ acetate and the specific $H_2$ production rate was as 9.8 ml $H_2/g$ cell${\cdot}$h, The fact that a single strain can perform both dark- and light-fermentation gives a great advantage in process development Compared to a one-step dark-fermentation, the combined dark- and light-fermentation can increase the $H_2$ production yield on glucose by two-fold.

• 한국식품조리과학회지
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• 제15권1호
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• pp.61-67
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• 1999

The effects of salting methods on Kakdugi (cubed radish kimchi) fermentation were evaluated. Kakdugi was prepared with various salting methods, salt concentrations, and settling times, and fermented at 10$^{\circ}C$ for up to 52 days. Radish (Raphanus sativus L.) cubes (2 cm size) were salted by using the following methods salt concentration of about 1.5% which was known appropriate for the organoleptic quality of Kakdugi: 1) Treatment S-1: applying dry salt uniformly onto the radish cubes, with a salt concentration of about 1.5% (w/w) and cured for 1 hr, 2) Treatment S-5: applying dry salt uniformly onto the radish cubes, with a salt concentration of about 1.2% (w/w) and cured for 5 hr, 3) Treatment B-1: brining radish cubes in a 8.5% (w/v) salt solution for 1 hr, 4) Treatment B-5: brining radish cubes in a 4.0% (w/v) salt solution for 5 hr. As the fermentation continued, the initial high decrease in pH has been retarded in all the treatments, of which the delaying extent was more significantly noted from B-1 and B-5 than S-1 and S-5. The pH of the Kakdugi which showed a good eating quality dropped to 4.3∼4.8 with the accumulation of total acids. Total vitamin C increased sharply at the palatable period of Kakdugi during the initial fermentation and then decreased gradually following a sigmoidal changing pattern. The reducing sugar levels were also influenced by salting methods and fermentation as sugars are converted into acids. High initial contents of reducing sugars and their subsequent rapid decrease were observed in “S” group than “B” group during fermentation. For nonvolatile organic acids, lactic acid increased consistently throughout the fermentation while malic acid, which was high at the initiation of fermentation, decreased rapidly afterwards at the palatable period of Kakdugi.

• 동아시아식생활학회지
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• 제19권5호
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• pp.776-782
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• 2009

This study was conducted to develop functional soybean paste with krill (Euphausiacea) as compared to a conventional soybean paste (S1). Soybean containing 10%, 20% and 30% (w/w) krill (S2~S4, respectively) was prepared and quality characteristics (moisture, crude fat, crude protein, ash, reducing sugar, pH, titratable acidity, total acidity and buffering power) were assessed during fermentation for 150 days. As well, antioxidative activities of krill soybean paste were compared to those of control soybean paste based on total phenolic compound content and free radical scavenging activity, including the 1,1-diphenyl-2-picryl-hydrazil (DPPH) scavenging activity and the thiobarbituric acid value (TBA value). The moisture content of all samples decreased to 41.91~53.47% during fermentation, while the crude fat increased to 1.98~5.21% with increasing addition of krill. Additionally, crude protein increased slightly to 8.24~14.08% with increasing addition of krill after 120 days of fermentation. Ash content was 15.96~18.92%. The reducing sugar content of S2, S3 and S4 was higher than those of S1 with increasing length of fermentation. S2, S3, and S4 displayed progressive decreases in pH and progressive increases in titratable acidity compared to S1. The total acidity of all samples was increased, while the buffering power was decreased with increasing fermentation. Especially, the buffering power of S1 was lower than that of S2, S3 and S4. DPPH radical scavenging activity of lipophilic extracts from S2, S3 and S4 was slightly higher than those of S1. However, the radical scavenging activity of hydrophilic extracts from all samples had similar tendencies, regardless of the krill content or fermentation period. Total phenolics increased with increasing fermentation time and TBA value increased with increasing fermentation time and krill content.

• 한국식품영양학회지
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• 제33권5호
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• pp.524-531
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• 2020

The purpose of this study was to evaluate the quality properties of Meju prepared by inoculating two strains of Bacillus amyloliquefaciens HJ5-2, and Aspergillus oryzae PS03. The three soybean varieties that include Daewonkong, Daechan, and Saedanbaek were used in this experiment. The fermentation temperature during the Meju aging varied at 20℃, 30℃, and 40℃, respectively. The physicochemical analysis of the soybeans, showed that the cured protein and fat contents were 34.83~43.49% and 12.91~18.90%, respectively. The pH and total acidity were 6.47~6.93 and 0.11~1.22%, respectively. The change in appearance of the Meju was that the yellow-green mold was well formed on seven days at fermentation temperature of 20℃ and 30℃, but at 40℃, there was minimal mold formation and cracking of the surface. The amino nitrogen content was highest on the Daechan Meju at 621.83 mg% for seven days. The amylase increased as the fermentation period increased in all samples, and the protease increased rapidly until the first day of the fermentation, and then gradually increased thereafter. The total number of bacteria increased or decreased as the fermentation proceeded to 6.66~10.07 log CFU/g. The mold counts increased with increasing fermentation period in the range of 6.38~8.79 log CFU/g.

• 한국식품영양학회지
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• 제29권2호
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• pp.237-245
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• 2016

In this study, the physicochemical and sensory characteristics of low-salt Myungran jeotkal (Alaskan pollock roe) were evaluated after fermentation at $4^{\circ}C$ and $20^{\circ}C$ with or without the addition of deep sea water, salt from deep sea water, and vegetable-origin lactic acid bacteria (Lactobacillus fermentum JS, LBF). When fermented at $20^{\circ}C$, the addition of LBF to Myungran jeotkal resulted in a slow increase in lactic acid content, followed by an abrupt increase after five days of fermentation. However, when fermented at $4^{\circ}C$, the lactic acid content did not change significantly. Further, when Myungran jeotkal fermented at $4^{\circ}C$, the pH decreased as lactic acid production increased. The salinity of Myungran jeotkal fermented at $4^{\circ}C$ and $20^{\circ}C$ was 7% and was not affected by fermentation period. When fermented at $20^{\circ}C$, volatile basic nitrogen and amino nitrogen contents increased with increasing duration of fermentation. Further, volatile acid content decreased, however, the content of amino nitrogen increased after 11 days of fermentation with LBF and no salt effects were observed. When fermented at $20^{\circ}C$ for 13 days, preference (sensory evaluation) was the highest in all experimental groups after 9 days of fermentation, and then decreased as the fermentation period increased. The free amino acid content was highest (1,648.8 mg/100 g) in Myungran jeotkal when sun-dried salt and LBF were added, 2.3 times higher than in the control.