• Applied Biological Chemistry
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• v.50 no.4
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• pp.281-286
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• 2007

The effects of green tea powder (GTP) on kimchi quality were evaluated by investigating acid production, growth of lactic acid bacteria, sensory properties, and several volatile odor components of GTP-added kimchi. The concentrations of GTE added to kimchi were 0.2, 0.4, 0.6 and 1.2% (w/w) of salted Chinese cabbage. The pH of kimchi with higher amounts of added GTP increased with ripening. The acidity of unripened kimchi or kimchi ripened for one day generally increased with the addition of GTP, while that of kimchi ripened for two or three days generally decreased with the addition of GTP. Addition of GTP had no significant effect on the lactic acid bacterial count of kimchi. Scores of overall acceptability, taste and odor of 0.2 or 0.4% GTP-added kimchi were higher than those of other samples, whereas scores of color decreased with increasing amount of GTP added to kimchi. Texture of kimchi added with higher amounts of GTP and ripened for two or three days resulted in lower score than the reference sample. Diallyl sulfide and methyl trisulfide were newly produced with the ripening of kimchi, and the amounts of some volatile odor components in kimchi were changed during ripening.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.937-942
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• 2003

Kimchi was prepared with 5, 10 or 20%(w/v) Chinese radish and ripened at $20^{\circ}C$ for 3 days. Acid production and growth of lactic acid bacteria, sensory properties, and several volatile odor components in kimchi were examined. The effects of freeze-drying on the quality of kimchi were also studied. The pH of the control (kimchi prepared without Chinese radish) was 4.31 and gradually decreased as the amount of Chinese radish increased. The acidity of the control was 0.673% and gradually increased as the amount of Chinese radish increased. Viable counts of lactic acid bacteria in the samples did not differ significantly from the control. The pH of freeze-dried/rehydrated kimchi slightly decreased as the amount of Chinese radish increased while its acidity gradually increased. The viable count of lactic acid bacteria of freeze-dried/rehydrated kimchi did not differ significantly as the amount of Chinese radish increased. Overall acceptability and taste of kimchi and freeze-dried/rehydrated kimchi generally improved by the addition of 10% or 20% Chinese radish. Six volatile odor components including ethanol and five sulfur-containing components (SCC) were identified from unripened kimchi, and the level of two SCCs increased as the amount of Chinese radish increased. Eight volatile odor components, ethanol and seven SCCs, were identified from ripened kimchi and the level of five SCCs increased as the amount of Chinese radish increased. Diallyl sulfide and methyl trisulfide were newly detected from the ripened samples, but not from the unripened kimchi. Freeze-drying substantially reduced all of the volatile odor components from kimchi. Five volatile odor components including ethanol and four SCCs were identified from the freeze-dried/dehydrated samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1006-1012
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• 1997

To observe the food quality of Baik-kimchi which is known as a watery Chinese cabbage pickles without fish sauce and red pepper paste, the changes of dietary fibers and pectic substances during fermentation at 5$^{\circ}C$ and $25^{\circ}C$ were studied. Baik-kimchi fermented at $25^{\circ}C$ showed a greater changes in pH and acidity than those of 5$^{\circ}C$ during storage. Ripened Baik-kimchi products fermented at 5$^{\circ}C$ could be prepared on 9~12 days of fermentation, and those had a pH range from 4.25 to 4.40 and acidity of 0.34~0.53. But in the case of $25^{\circ}C$ fermentation, Baik-kimchi ripened for 3 days showed a pH of 4.02 and acidity of 0.54. The pH and acidity of the Baik-kimchi juice changed more rapidly than those of the Baik-kimchi solid regardless of fermentation temperatures. The content of soluble dietary fiber(SDF) was ranged from 3.06 to 4.87% at 5$^{\circ}C$ and a wide variation in SDF was observed in the sample fermented at $25^{\circ}C$(4.15~11.22%). Insoluble dietary fiber(IDF) were increased from 21.66% to 28.42% in solid of Baik-kimchi during fermentation at 5$^{\circ}C$ and ranged from 21.37% to 24.65% for sample fermented at $25^{\circ}C$. A notable amount of pectin had been dissolved in juice of Baik-kimchi till the best ripening time and showed the level of 223.2mg/100ml at 5$^{\circ}C$ on the day of 9 and 207.3mg/100ml at $25^{\circ}C$ on the day of 2. In contrast, the contents of pectin in solid Baik-kimchi decreased, whereas contents of sodium hexametaphosphate soluble pectin(HXSP) and HCl soluble pectin(HClSP) increased with fermentation period.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.601-607
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• 2018

We examined the physicochemical characteristics of radish kimchi supplemented with either 10% boneless or boned sliced gizzard shad (BLGS and BGS, respectively) and compared them to those of untreated kimchi during an eight-week fermentation period. BLGS- and BGS-containing kimchi showed higher acidity, amino nitrogen, and Lactobacillus levels than control kimchi. Furthermore, BGS-containing kimchi showed higher acidity, amino nitrogen, and Lactobacillus levels, and lower reducing sugar contents than BLGS at the optimum- and over-ripened stage. Higher amino nitrogen serves as a good medium for microorganism growth, which produce organic acids, consequently decreasing the reducing sugar, pH levels and increasing the acidity. The preference test showed that the control kimchi was the most preferred at the unripened stage, while the BLGS- and BGS-supplemented kimchi samples in the ripened and over-ripened stages showed similar preferences. In conclusion, our results indicate that gizzard shad-supplemented kimchi shows positive health characteristics, such as low salinity, high amino nitrogen and Lactobacillus levels.

• Preventive Nutrition and Food Science
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• v.5 no.4
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• pp.189-193
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• 2000

Preservative and antimutagenic effects of green tea leaves added Chinese cabbage kimchi (GK1, GK2, GK3, and GK4 : 1, 2, 3 and 4 of green tea leaves (GTL) in proportion of 100 of salted Chinese cabbage were added to kimchi) were compared to those of the Chinese cabbage kimchi without GTL (control kimchi, CK). Fermentation period of GKs was further delayed than that of CK. The initial pH and acidity between GKs an CK were similar, but the time reach optimally ripened status of kimchi (pH 4.3) was different. CK took 6 days, while GK1, GK2, GK3 and GK4 took 6, 10, 12 and 14 days at 10℃, respectively. The growth of Leuconostoc sp. and Lactobacilus sp. in GKs delayed comparing to those in FCK. Among GKs, as the added amount of green tea leaves increased, the growth of lactic acid bacteria was retarded. The antimutagenic effects of juices from GKs and CK were studied against aflatoxin B₁(AFB₁) in the Ames test on Salmonella typehimurium TA100 and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in the SOS chromotest using E. coli PQ37. Juices from optimally ripened GKs (pH 4.3) showed 52∼76% inhibition rates against the indirect mutagen, aflatoxin B₁ induced mutagenicity while 49% inhibition rate by CK in the Ames test. Juices from GKs and CK showed 44∼67% and 36% inhibition rate against direct mutagen, MNNG (70 ng/assay) induce mutagenicity in the SOS chromotest. Thus GKs delayed fermentation period of kimchi and exhibited higher antimutagenic activity than CK.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.123-128
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• 2004

Effects of jeotkal (salted-fermented seafoods) addition on acid production, growth of lactic acid bacteria, sensory properties, and volatile odor components of kimchi were investigated. Changes in pH and acidity of kimchi added with myulchi-aekjeot, kanari-aekjeot, and aekche-Jukjeot were similar to, whereas those of saeu-jeot sample on 0, 2, and 4 days of ripening were slightly different, those of control sample. Changes in pH and acidity of jogae-jeot sample during whole ripening period were markedly different from those of other samples. Numbers of lactic acid bacteria of all samples on 0 and 4 days were $1.8-2.6{\times}10^{5}\;and\;1.0-2.5{\times}10^{9}\;CFU/mL$, respectively. Overall acceptability and taste of kimchi added with jeotkal except jogae-jeot were higher than those of control sample, with saeu-jeot-added kimchi showing the highest scores. Eight volatile odor components were identified in 6-day-ripened kimchi samples, and those of saeu-jeot sample were slightly higher than those of other samples. Diallyl sulfide and methyl propyl disulfide were produced in 6-day-ripened samples. Ethanol, methyl allyl sulfide, and dimethyl disulfide concentrations increased, whereas that of allyl mercaptan decreased in 6-day-ripened samples compared to unripened ones.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.4
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• pp.511-519
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• 2007

This study was conducted to estimate the drift of change for kimchi purchase, and to contribute to quality improvement of kimchi sold at markets. Questionnaries were distributed to 450 adults and 396 were statistically analyzed. The methods used to analyze the items were frequency analysis, Chi-square, t-tests and ANOVA. The highest preference for kinds of kimchi was Beachoo kimchi, while the preference for Nabak kimchi was low. In terms of the degree of ripening, most subjects preferred properly ripened kimchi. With regard to the purchase amount the subjects preferred 1 kg and mainly purchased it once every three months at large market and supermarkets. The main reason for purchasing kimchi at markets was 'convenience', while the reason they didn't purchase it was 'it might contain artificial seasoning'. With regard to the development and improvement of the kimchi industry, the subjects belived that taste and ripening should be standardized, and that kimchi should be treated sanitarily. They acknowledged that kimchi products should be diversified, and active marketing should be carried out in order for it to be globalized.

• Preventive Nutrition and Food Science
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• v.6 no.2
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• pp.117-121
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• 2001

Changes in antioxidative activity and Angiotensin converting enzyme(ACE) inhibitory activity in juice prepared from Dolsan leaf mustard kimchi (DLMK) ar various fermentation temperatures were investigated. Antioxidative activity of juice from optimally ripened DLMK at 20 and 3$0^{\circ}C$ showed 80 and 83%, respectively. Juice from 10-day fermented DLMK at 3$0^{\circ}C$ showed 62% inhibitory activity against the ACE. In the juice fermented DLMK at 2$0^{\circ}C$~3$0^{\circ}C$, physiological activity was higher than that of the 4~1$0^{\circ}C$. In particular, optimally ripened DLMK at 3$0^{\circ}C$ showed the highest physiological activity. The physiological activity in DLMK juice at the fermentation period increased significantly with an increase in the growth of microbes. Consequently, a maximum physiological activity was shown at the maximum cell number. These results suggest that the microorganisms in DLMK juice would play an important role in the physiological activity.

• Preventive Nutrition and Food Science
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• v.2 no.3
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• pp.241-245
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• 1997

Inhibitory effects of kimchi extracts on arcinogen-induced cytotoxicity and transformation in C3H/10T1/2 cells were studied. The methanol extract (500㎍/ml) of fresh (unfermented kimchi), and 3-week-fermented kimchi (properly ripened kimchi at 5℃) inhibited 3-methylcholanthrene (MCA)-induced cytotoxicity in C3H/10T1/2 cells by 84 and 99%, respectively. The inhibitory effect of 3-week-fermented kimchi was higher than that of the fresh kimchi at same test condition. The methanol soluble fraction, and haxane extract of 3-week fermented kimchi also surpressed the cytotoxicity of FC3H/10T1/2 cells mediated by 7,12-dimethylbenz[a]anthracene(DMBA) and N-methyl-N'-nitro-N-nitrosoguanidine(MNNG). Furthermore, MCA-induced transformation of C3H/10T/1/2 cells was significantly inhibited by the methanol soluble fraction of 3-week fermented kimchi. With these results, we suggest that kimchi might have anticarcinogenic effect in part due to inhibition of carcinogen-induced cytotoxicity and transformation of C3H/10T/1/2 cells.

• Journal of the Korean Society of Food Culture
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• v.36 no.3
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• pp.274-283
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• 2021

What is the origin of kimchi and what changes did it go through to become the kimchi of today? Also, what makes kimchi different from other pickled vegetables such as Chinese paochai, Japanese tsukemono, and Western pickles, and sauerkraut, and what is the identity of kimchi? This study is the result of thought on these fundamental questions about kimchi which is the only pickled vegetable distributed around the world that uses a fermented and ripened animal seasoning called jeotgal (salted marine life) to dramatically improve its umami taste and nutritional value, thereby securing its uniqueness. Kimchi has further evolved into a unique and high-quality pickled vegetable through the use of its specialized seasoning, adopting a composite fermentation mechanism and absorbing new ingredients such as red pepper. It is expected that this paper will invigorate the discussion on the firm establishment of the identity of kimchi and the future direction that it may take.