• Journal of the Korean Society of Food Culture
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• v.11 no.2
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• pp.207-215
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• 1996

This study was carried out to find the effects of salt and other materials on the taste and fermentation of kimchi. Several parameters such as pH, acidity, salt concentration and sensory evaluation during fermentation at $20^{\circ}C\;and\;5^{\circ}C$ (after keeping at $20^{\circ}C$ for 24 hours) were used. The results are as follows: As the fermentation period increases the pH of kimchi decreases. The pH of all samples rapidly decreases to 4.2. During fermentation, the acidity at 3 hours was higher than at 5, 8 and 12 hours. For in the sensory evaluation during fermentation, kimchi salted for 5 hours showed a higher score than those salted for 3, 8 and 12 hours. During the storage period, the pH of kimchi with salted oysters rapidly decreased. A sensory evaluation done during the storage period, showed that earlier on in the storage, kimchi with salted oysters was scored higher than kimchi with other Jeotkals. The leek-added kimchi was also highly scored.

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.321-327
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• 2022

In the present study, we investigated the physicochemical characteristics and antioxidant activity of kimchi during the fermentation process. Kimchi was fermented at 18.5 ℃, then after one day, the storage temperature was changed to 5 ℃ without fresh kimchi (Fresh; pH 5.6, total acidity 0.3%), which obtained optimum-ripened kimchi (OptR; pH 4.3, total acidity 0.64%), and over-ripened kimchi (OvR; pH 3.8, total acidity 1.24%). As a result, the glucosinolates content of the kimchi was increased during the fermentation process. Among the glucosinolates, glucoraphanin possesses the highest amounts in kimchi. In addition, the contents of sulforaphane and total polyphenol, which are common antioxidant compounds, were increased during the fermentation process. To evaluate the antioxidant activities of Fresh, OptR, and OvR, we measured 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl (·OH) radicals radical scavenging activity in vitro. Fresh, OptR, and OvR exerted DPPH and ·OH radical scavenging activities dose-dependently. In particular, the ·OH radical scavenging activities of OptR and OvR were higher than that of Fresh. Therefore, we suggest that kimchi at the ripe and over-ripe stage is considered to have high antioxidant activity by increasing glucosinolate, sulforaphane, and total polyphenols, compared with fresh kimchi.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.573-579
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• 2008

In this study, kimchi containing Styela clava (Korean name: miduduk) was prepared, and the quality of the prepared kimchi was evaluated during 4 weeks of fermentation at $4^{\circ}C$. S. clava was added to salted cabbage at concentrations of 0, 1, 2, and 3%(w/w). The quality characteristics of the kimchi were determined by measuring pH, titratable acidity, salinity, color, and microbial amounts. All kimchi evidenced a rapid decrease in pH until 2 weeks, and then a gradual decline thereafter. Titratable acidity increased gradually until 2 weeks, then sharply increased thereafter. Salinity increased until 3 weeks. We noted only slight overall color differences between the kimchi samples. Total microbial and lactic acid bacterial counts achieved maximum levels at 3 weeks, and the kimchi to which 1 and 2% S. clava was added evidenced values higher than that of the controls. In our sensory evaluations, the kimchi to which 2% S. clava was added was scored highest in terms of color, flavor, and overall acceptance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.274-278
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• 1996

토마토 과실의 연화현상의 주 원인으로 판단되는 세포벽의 형태적 변화를 조사하기 위하여 성숙 단계별로 취하여 과실의 경도, 세포벽 구성 성분의 변화 및 세포벽의 변화를 조사하였다. 과육의 경도는 적숙기 이후부터 급셕한 감소를 나타내었다. 세포벽 함량은 성숙 중에 감소하였고 가용성 펙틴의 증가와 불용성 펙틴의 감소는 적숙기와 식용 적기 사이에서 가장 현저했으며, 총 펙텐의 함량은 다소 감소하는 경향을 나타내었다. 성숙에 따른 토마토 과육의 세포 및 세포벽의 형태적 변화를 현미경으로 관찰한 결과, 수확기까지의 토마토에서는 middle lamella와 세포내 기관들이 잘 관찰되었으나, 연화가 진행됨에 따라 식용 적기의 토마토에는 middle lamella를 관찰할 수 없었으며 과숙기 에서는 middle lamella의 가용화와 함께 세포벽의 부분적인 분해와 세포분리현상이 관찰되었다.

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.234-238
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• 2001

For the comparison of fermentation pattern of leek kimci with chinese cabbage kimchi, the changes of total viable cell number, Leuconostoc sp. bacteria, Lactobacillus sp. bacteria, pH and total sugar content of twotypes kimchies were investigated during fermentation at $20^{\circ}C$ and $10^{\circ}C$. In chinese cabbage kimchi at $20^{\circ}C$ fermentaion, the numbers of total viable cell, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria reachedthe maximum level on 2nd day and reduced slowly. But in leek kimchi, the maximum numbers of total via-ble cells, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria were obtained after 3 days fermentation,and the cell number of Lactobacillus sp. maintained at the maximum level oyer 15 days. At $10^{\circ}C$ fer-mentation, in both kimchies, the viable cell number of lactic acid bacteria more slowly increased anddecreased than at $20^{\circ}C$. The pH of chinese cabbage kimchi was 4.2 on 3rd day (optimal ripening phase) andmere decreased to 3.5 after 5 days, but in leek kimci the pH 4.2 could be reached after 10 days at $20^{\circ}C$. At $10^{\circ}C$, the optimal ripening pH 4.2 of chinese cabbage kimchi was reached after 6 days, but in leek kimchieven though after 24 days, the pH was maintained oyer 4.3. The total sugar contents of chinese cabbage him-chi and leek kimci were decreased continuously during fermentation. From these results, we know that thefermentation of leek kimchi proceed more slowly than chinese cabbage kimchi by the retardation of lacticacid bacteria growing in leek kimchi.

• Food Science and Preservation
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• v.21 no.4
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• pp.468-472
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• 2014

The effect of pre-storage treatments was investigated to control the occurrence of fruit skin stain in 'Niitaka' pears. The incidence of fruit skin stains was significantly reduced when the fruits were stored in paper bags with a yellow inner color, compared to when they were stored in paper bags with blue and red inner colors. Additionally, the pear fruits that were harvested seven days earlier than their optimum maturity date developed less fruit skin stains in cold storage and retained their quality. Storage in polyethylene (PE) bags did not control the occurrence of fruit skin stains as effectively as did bag-free storage or storage in calcium-coated bags. The dipping of the pear fruits in a chlorine dioxide and calcium solution was highly effective in reducing the fruit skin stains compared to when they were not dipped or when they were dipped only in distilled water. In particular, a 1,500 times diluted solution of sodium dichloroisocyannurate (NaDCC) reduced the incidence of fruit skin stains and the size of the lesions. No stain was observed on the skin of the fruit with a water content lower than 67.7% (w/v) during its storage. In conclusion, packaging pear fruits in bags with an inner calcium coat and dipping them in a chlorine dioxide, calcium, or NaDCC solution can effectively reduce their skin stains during their storage.

• Bulletin of Food Technology
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• v.21 no.2
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• pp.55-61
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• 2008

본 연구에서는 발효기간 중 SAM 생성량 증진김치의 최적조건을 개발하기 위해 배추김치의 재료별 및 제조법에 따른 발효기간 중의 SAM 함량 변화를 측정하였다. 발효가 진행됨에 따라 모든 김치군의 pH는 발효초기에는 급격히 감소하다가 후기에는 pH $4.2{\sim}4.3$으로 비슷하게 나타났다. 산도는 pH와 비슷한 경향을 보이면서 발효초기에는 급격히 감소하다가 후기에는 서서히 증가하는 경향을 보였다. SAM 함량은 가장 기본적인 재료로만 제조한 표준(A)김치는 가장 낮게 나타났고, SAM이 검출되는 원 부재료에 SAM 함량이 많은 김치가 SAM 함량도 높게 나타났다. 모든 김치군 중 I김치가 가장 높은 SAM 함량을 나타냈으며, 김치별 SAM 함량이 가장 높은 발효시점은 A, K김치는 pH $4.6{\sim}4.9$, 산도 $0.38{\sim}0.57$0.57, D, H김치는 pH 6.3, 산도 $0.24{\sim}0.27$, E, G김치는 pH $6.1{\sim}6.6$, 산도 $0.05{\sim}0.14$0.14, B, C, F, I, J김치는 pH $4.3{\sim}5.3$, 산도 $0.45{\sim}1.02$에서 나타났다. 따라서 대부분의 김치는 적숙기시점이 되었을 때 B, E, G, H김치는 초기발효 때부터 SAM 함량이 높게 나타났다. 또한 발효가 진행됨에 따라 SAM 함량은 감소하는 경향을 보였다. 따라서 연구결과 주재료인 채소류와 젓갈의 함량비를 적절히 제조하여 최적의 SAM 생산능력의 발효시점과 김치맛에 영향을 끼치지 않는 관능적으로 적합하고 SAM 생성이 보다 효과적으로 유도되는 최적의 조건에 대한 실험들이 추가적으로 필요하다고 판단된다.

• Korean Journal of Food Science and Technology
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• v.19 no.3
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• pp.250-256
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• 1987

An attempt was made to establish a simple and rapid method for the evaluation of Kimchi quality. Four kinds of Kimchi included one home made traditional Kimchi were stored at $4^{\circ}C$ and$25^{\circ}C$ and biochemical changes, including pH, total acidity, volatile acidity, volatile basic nitrogen, vitamin C, NaCl, glucose, nitrite and resazurin value were determined and tested for the relationship with sensory evaluation. The change in pH, total acidity and resazurin value were highly correlated with the sensory maturity of Kimchi-Resazurin value was strongly influenced by the sample dilution and fermentation temperatures. It was concluded that resazurin test with sample solution of $2{\sim}4%$ could be used as a rapid method for the estimation of the maturity of Kimchi.

• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.443-450
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• 1984

Chemical and microbial changes during Kimchi (a group of Korean seasoned pickles) fermentation were carried out at various temperatures and salt concentrations. The time reaching optimum ripening of Kimchi varied depending upon fermentation temperature and salt concentration. At high temperature and low salt content Kimchi fermentation was faster than at low temperature and high salt content. The ratio of volatile to non-volatile acids reached its maximum at the optimum ripening time of Kimchi and decreased thereafter. Leu. mesenteroids, Lac. brevis, Lac. plantarum, Ped. cerevisiae, Str. faecalis and low acid producing Lactobacilli were isolated from Kimchi samples. However, the main microorganism responsible for Kimchi fermentation was Leu. mesenteroides and Lac. plantarum was the main acidifying organism. Total viable count increased rapidly in the beginning of fermentation and reached its maximum number at optimum ripening time and then decreased slowly as the acidity of Kimchi increased. While the total aerobic bacteria and fungi decreased during Kimchi fermentation, the yeast increased significantly at lower temperature.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.331-337
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• 1989

In order to investigate the method for extension of shelf-life of Kimchi, the effect of low temperature heating and addition of mustard oil on pH and total acidity of Kimchi during storage at $15^{\circ}C$ were studied. Mustard oil was found to have the antimicrobial effect on the major lactic acid bacteria of Kimchi such as Lactobacillus plantarum, Lactobacillus brevis, Leuconostoc mesenteroides and Pediococcus cerevisiae, Addition of 200p.p.m. mustard oil, 0.1% mustard powder and 0.01% $H_2O_2$ to Kimchi effectively reduced the fermentation rate of Kimchi. Low temperature heating of salted cabbage and addition of 200p·p.m. mustard oil and 0.01% $H_2O_2$ to seasonings extented the time reaching optimum ripening of Kimchi about 2.5 times longer than control. Combination of low temperature heating, addition of mustard oil and $H_2O_2$ to seasonings and post low temperature heating delayed fermentation time Kimchi about 5 times longer than control after 15 days storage at $15^{\circ}C$.