• Korean journal of food and cookery science
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• v.21 no.2 s.86
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• pp.195-200
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• 2005

Three different commercial Kimchi industry-made packaged, department store-made and ordinary market-made were analyzed for their pH, acidity and microbiological characteristics including certain harmful bacteria on selective media during a storage-fermentation period of 7 days at $2^{\circ}C\;or\;20^{\circ}C$ The pH of all the Kimchi samples wasdecreased from 5.85 to 3.82 and their total acidities increased from 0.2 to 1.18 as the fermentation continued during the storage-fermentation. E. coli and Salmonella sp. of $0\~1101$ cfu/mL were found in the industry-made Kimchi just after purchase time. As the storage-fermentation proceeded, the viable numbers of these bacteria had been reduced in all Kimchi samples tested and no bacteria were detected after 5 days at $2^{\circ}C$ and 2 days at $20^{\circ}C$, respectively. On the other hand, a range of $7.9102\~2.9103$ cfu/mL of Staphylococcus sp. was detected in the department store-made and ordinary market-made Kimchi samples at the purchase time, which was higher than that of the industry-made Kimchi, and this range wasn't reduced during storage-fermentation. The viable number of yeasts in the market-made Kimchi was 2.1103 cfu/mL. These results suggest that some commercial Kimchis were contaminated by some harmful bacteria and that a portion of these bacteria remained alive in the Kimchi, even with high acidity during the edible period.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.25 no.2
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• pp.31-35
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• 2019

Kimchi is a refreshing sour food which gives sour and carbonic acid taste of carbon dioxide produced during the fermentation process. So, carbon dioxide injection was tried to raise carbonic acid taste of kimchi stored in the airtight container. First, carbon dioxide injection times of a given gas supply system were determined experimentally to attain initial concentration of 80% for different solid/liquid ratios. Since carbon dioxide is dissolved in kimchi to decrease its concentration during storage, periodical carbon dioxide injection conditions were needed and determined to keep the $CO_2$ concentration above 70%. For the initial flushing to 80% $CO_2$ concentration in model system filled with water, the injection time ranged from 40 to 89 seconds for free volumes of 2-8 L. $CO_2$ injection conditions for the under-ripened storage at $10^{\circ}C$ consisted of longer time at more frequent cycles for watery kimchi than for Chinese cabbage kimchi. At $0^{\circ}C$ of subsequent ripened stage storage of watery kimchi, the periodical injection at 3 hour interval was required because of continuous dissolution of carbon dioxide. However, Chinese cabbage kimchi did not require subsequent $CO_2$ injection during the ripened state storage and needed only flushing to 80% $CO_2$ at time of the container opening and closing. These results can be used as basic information for the programmed control of $CO_2$ injection in the kimchi container system.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.11 no.2
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• pp.97-100
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• 2005

To delay the fermentation of Kimchi during storage and handling, adipic acid, was selected due to its low acid dissociation constant. Sensory evaluation was conducted to find maximum dosage of adipic acid which does not influence the raw taste of Kimchi and 0.12%(wt. of adipic acid/wt. of Kimchi) was selected. At $10^{\circ}C$, the optimum and maximum shelf life was respectively 3.2 and 2.3 times longer than that of control. At 15 and $20^{\circ}C$, extension of shelf life was as follows: maximum shelf life with adipic acid was extended about 2.3-2.7 times and optimum shelf life was 1.3-1.5 times.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.216-221
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• 2007

Microbiological, chemical and sensorial quality changes of kimchi, which was manufactured with sanitized materials by ozone and gamma irradiation, were investigated during storage. The number of total aerobic bacteria in control was increased rapidly by storage and decreased after 10 days of storage. However, the kimchi which was manufactured with materials treated with ozone or gamma irradiation showed a lower rate of increase. The number of lactic acid bacteria was lower in control than in treatments. Gamma irradiation of 3 or 5 kGy showed the lowest change of microbial population in kimchi during storage. pH, acidity and sensory quality were also rapidly changed in control whereas those of ozone or irradiation treated sample was slower. Therefore, cold pasteurization of materials before kimchi manufacturing provide a slower fermentation, resulting into the extension of storage quality for kimchi.

• Korean Journal of Food Science and Technology
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• v.42 no.2
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• pp.160-164
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• 2010

This study examined the safety of various salts (domestic purified salt, domestic solar salt, imported purified salt, imported solar salt) as well as the effects on the quality of kimchi fermented during 28 days at $4^{\circ}C$. All salts contained DEHP, but ferrocyanide ion and heavy metals (Cd, Pb, As, Hg) were not detected. Following fermentation, the pH of kimchi was decreased during storage, but total acidity and salinity values increased. There was no considerable differences between the various salts. As the fermentation period increased, the lactic acid bacterial counts increased remarkably. Regarding the sensory characteristics of kimchi during storage, the appearance of domestic purified salt was better than that of domestic solar salt following fermentation. Imported salts produced a strong salty taste initially, but domestic refined salt had the highest salty taste at 7 days. Therefore, there were no considerable differences between the various salts.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.661-668
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• 2008

This study was investigated to determine the conditions for an auto-aging system placed within a kimchi refrigerator for optimal fermentation, as well as the optimal conditions for the prolongation of dongchimi storage time. Various fermentation characteristics of dongchimi stored at different temperatures ($5-23^{\circ}C$) were compared. The pH and acidity of dongchimi associated with the highest levels of overall acceptability were $3.9{\pm}0.1$ and $0.25{\pm}0.05%$, respectively. In order to establish the time point for the conversion of fermentation to storage, dongchimi was fermented at $10^{\circ}C$ or $15^{\circ}C$ until the acidity reached the designated points (0.1, 0.2, and 0.3%), and was then stored at $-1^{\circ}C$ for 1 week. According to the sensory evaluation, the dongchimi acidity of 0.2% fermented at $10^{\circ}C$ evidenced the highest levels of overall acceptability after 1 week of storage among the samples. In conclusion, we suggest conditions of $10^{\circ}C$ and $-2.5{\pm}0.5^{\circ}C$ for the fermentation and storage temperature, respectively, and a dongchimi acidity of 0.2% as an index for the time point for the conversion of fermentation to storage in the kimchi refrigerator.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1043-1047
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• 2002

This study was carried out to investigate the effect of packaging materials (Ny/PE, PET/Al/PE, PET/PE/LDPE/CPP, PET/Al/Ny/CPP films, and bottle) and packaging methods (atmosphere and vacuum) on the physicochemical properties of Onion Kimchi and Rosemary-onion Kimchi stored at $5^{\circ}C$. Reducing sugar contents and pHs of Onion Kimchi and Rosemary-onion Kimchi decreased, whereas levels of titratible acidity and vit C contents increased with increasing the storage time. The fermentation of Rosemary-onion Kimchi was slower than that of Onion Kimchi. PET/PE/LDPE/CPP film was the most effective for Onion Kimchi packaging among all packaging materials tested.

• Food Science and Preservation
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• v.10 no.2
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• pp.136-141
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• 2003

This they was conducted to investigate the surface treated effect of Packaged kimchi on the PH, acidity, total microbe, number of lactic acid bacteria, browning and formation of off-flavor during storage at 10$^{\circ}C$. Kimchi was treated with 70% ethanol(1 time spraying) and attachment of polyethylene film(PE) on the surface of packaged kimchi and stored at 10$^{\circ}C$. pH of the control and ethanol treated kimchi stored for 15 days was decreased to 4.0 level but, the pH of PE-treated kimchi maintained over pH 4.0 until 21 days of storage. The aridity was the same tendency as the pH, which showed delaying of fermentation by PE treatment. Total microbe of PE treated kimchi was lower and number of lactic acid bacteria was higher than those of control and ethanol treated products, respectively. Degree of browning and off-flavor of control and ethanol treated kimchi increased from 13 days of storage, but the degrees of the PE-treated kimchi was lower during all storage periods.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.945-951
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• 2013

Changes in fermentation properties and ornithine levels of Baechu Kimchi by storage conditions were investigated. After making and fermenting Kimchi at $15^{\circ}C$ for 32 hr (S1), 36 hr (S2), 40 hr (S3), 44 hr (S4), and 48 hr (S5) during the first 10 days of storage. The Kimchi samples are subsequently stored in the -$1^{\circ}C$ Kimchi refrigerator for up to 60 days. Changes in the pH values and lactic acid contents of S4 and S5 samples are slightly bigger than the S1, S2 and S3 samples which have no significance differences. According to lactic acid bacteria (LAB) number, all samples show the largest augmentation according to the number of Lactobacilli during the first 20 days of storage. After 20 days of storage, the S4 and S5 samples show larger accumulations of LAB than S1, S2 and S3 samples. The Weissella genus is predominated at the 40 day of storage in the S5 sample. Ornithine levels are increased up to 170mg per 100 g during the storage period of 40~50 days in the S5 sample. However, the increase of ornithine levels in S1, S2 and S3 samples is smaller than those of the S4 and S5 samples. These results indicate that the conditions of Kimchi fermentation, which is 48 hr at $15^{\circ}C$ before storage, is proved to be the most superior for ornithine levels within the Kimchi refrigerator.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1715-1724
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• 2015

The combined effects of a sanitizer mixture solution and antimicrobial ice on the quality of salted Chinese cabbages were examined. Salted Chinese cabbages were treated with a sanitizer mixture (comprised 50 ppm aqueous $ClO_2$ and 0.5% citric acid), packed in 2% brine and antimicrobial ice, and stored for 12 days at 4 and $10^{\circ}C$. Microbiological data on the salted Chinese cabbages after washing with the sanitizer mixture indicated that the populations of total aerobic bacteria, and yeast and molds decreased by 2.20 and 1.28 log CFU/g after treatment with the sanitizer mixture. In addition, coliforms population of salted Chinese cabbage after 12 days storage at $4^{\circ}C$ in the combined mixture of the sanitizer and antimicrobial ice was 3.22 log CFU/g, which was a significantly different from that of control (5.46 log CFU/g). The combined treatment of sanitizer mixture, antimicrobial ice, and low temperature at $4^{\circ}C$ suppressed reduction of pH and elevation of titratable acidity, resulting in delaying the growth of lactic acid bacteria. Differences in salinity, hardness, and Hunter's $L^*$, $a^*$, and $b^*$ values among treatments were negligible during storage at $4^{\circ}C$. Therefore, this study suggests that a combination of sanitizer mixture, antimicrobial ice treatment, and low temperature storage could improve the microbial safety and quality of salted Chinese cabbages during storage.