• 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.34 no.4
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• pp.559-564
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• 2002

Volatile odor components of ripened and ripened/freeze-dried kimchi were analyzed by gas chromatograph. As ripening temperature of kimchi increased, pH of kimchi decreased, viable cell count of lactic acid bacteria of kimchi increased up to ripening temperature of $15^{\circ}C$, and sensory properties of kimchi gradually decreased. Allyl mercaptan, methyl allyl sulfide, dimethyl disulfide, diallyl sulfide, diallyl disulfide, and ethanol were detected in ripened kimchi and ripened/freeze-dried kimchi. The amounts of allyl mercaptan, methyl allyl sulfide, diallyl sulfide, and ethanol increased as the ripening temperature increased, while those of dimethyl disulfide and diallyl disulfide decreased. Freeze-drying for 24 hr removed most of the above-mentioned volatile odor components, which were further removed by freeze-drying for 48 hr.

• The Korean Journal of Food And Nutrition
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• v.7 no.4
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• pp.392-398
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• 1994

The purpose of this study was to predict the actions and roles of 10 strains of representative psychrotrophic lactic acid bacteria, in kimchi fermentation, which were Isolated from kimchi and identified as Leu. mesenteroides subsp. mesenteroides, Leu. mesenteroides subsp. dextranicum, Leu. lactic, Leu. paramesenteroides, Lac. bavaricus and Lac. homahiochii. For this, 0.01% of tactic starters were inoculated in germ free Korean cabbage-juice containing 2.5% NaCl, and then cultivated for 14 days at 1$0^{\circ}C$. All strains grew actively, and reached their stationary phase in 4 days. In death phase, the slopes of curves were much different each other by strains. The acidity increased rapidly between 2 and 4 days, and the pH decreased rapidly between 2 and 3 days. The total acidity was 0.5B~0.75%, the volatile acidity 0.04~0.18% and the pH 3.55~3.85, in final cultures. The cultures of Leuconostocs were better than those of lactobacilli on flavor test. It was thought that the ripening periods of kimchi would be much reduced, and that the over ripening would be also somewhat avoided, when these strains were used as starter bacteria for kimchi and the kimchi was fermented at low temperature.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.429-437
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• 1999

A mathematical model was established for estimating changes in pressure and volume of permeable kimchi packages. The model comprises the CO2 gas production from kimchi and permeation of O2, CO2 and N2 through the permeable film or sheet. Using the developed model, the effects of various packaging variables on the pressure and volume changes were analyzed for rigid and flexible packag es of kimchi(3% salt content) at 15oC, and then effect of storage temperature was also looked into. In case of rigid pack of 400g, using the plastic sheet of high CO2 permeability and initial vacuumizing can help to relieve the problem of pressure build up. The lower fill weight can further reduce the pressure, but will result in higher packaging cost. For the flexible package of 3 kg, highly permeable films such as low density polyethylene(LDPE) and polypropylene can reduce the volume expansion. Higher ratio of CO2 permeability to O2 and N2 permeabilities are effective in reducing the volume expansion. Increased surface area cannot contribute to reduction of volume expansion for highly permeable flexible packages of kimchi. For the impermeable packages, pressure and volume at over ripening stage (acidity 1.0%) increase with decreased temperature, while those at optimum ripening stage(acidity 0.6%) change little with temperature. Pressure of permeable rigid LDPE package increases with tem perature at any ripening stage, and temperature affects the volume of flexible LDPE package very slightly. Experimental verification of the present results and package design with economical consid eration are needed as a next step for practical application.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.160-167
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• 2019

This study was conducted to investigate the effect of initial ripening condition placed within a kimchi refrigerator and this result will be used as basic data for the development of fermentation system of Kimchi refrigerator. Hardness significantly decreased as the storage period longer. Lactic acid and Lactobacillus spp. showed a large amount until 8 weeks, but one without initial ripening contained much lower. The content of lactic acid bacteria increased from 4.50 logCFU/mL to 6.70 ~ 7.47 logCFU/mL and decreased to 5.08 ~ 6.10 logCFU/mL according to storage period. Consumer preferred $15^{\circ}C/52h$ samples rather than others in two weeks. $15^{\circ}C/36h$ and $6^{\circ}C/113h$ samples were significantly preferred during the whole storage period. These results indicate that the initial fermentation conditions affect the taste and fermentation degree of kimchi during the storage period.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.1
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• pp.35-40
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• 2021

Calcium hydroxide (CH) reacts with CO2 to produce moisture, and sodium carbonate (SC) reacts with CO2 in the presence of moisture. Using these different characteristics of these two reactants, a CH/SC mixture of CO2 absorber tuned for kimchi ripening to produce CO2 in a flexible package was selected. A ratio of CH:SC (1:2) in highly gas permeable microporous spunbonded film (Tyvek) sachet was found to be appropriate for delayed and consistent CO2 absorption useful for kimchi package. Addition of superabsorbent polymer (SAP) as moisture buffer was helpful for boosting the consistency of CO2 absorption. In a package of 0.5 kg kimchi at 10℃, the sachet consisting of 0.794 g of CH + 2.276 g of SC + 0.4 g of SAP suppressed its volume expansion and maintained a suitable range of CO2 partial pressure (PCO2) steadily inside. These optimal conditions may vary depending on the type and salinity of kimchi, storage and distribution temperature, and the material and area of the absorber sachet. This study showed a potential of mixture CO2 absorber to be tuned for CO2 producing packaged kimchi for the purpose of keeping consistent PCO2 at tolerable volume expansion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.2
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• pp.131-135
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• 1984

For the convenience of transportation and improvement of the utility of raw chinese cabbage during harvest season, the condition of pretreatment for the raw chinese cabbage with pickle has been examined by preserving for one to ten days. The changes in the content of riboflavin and ascorbic acid in kimchi (pickled-seasoned chinese cabbage), which was manufactured by using the pickled cabbage as a main raw material, along with ginger, garlic, red pepper powder, rad-dish and fermented shrimp as seasonings, during ripening were investigated with specially referred to palatability. The yield of the pickled cabbage compared to the raw cabbage after treating with pickle was 62 to 65% in volume and 15 to 42% in weight. After 10 days of pickling of the chinese cabbage, one-third of total ascorbic acid was diminished but no change in riboflavin content was observed. During ripening of kimchi, riboflavin content in kimchi processed with the pickled cabbage has not been changed compared to the content in convention- ally made kimchi, however, slight decrease in ascorbic acid content in the kimchi processed with the pickled cabbage was as certained. The result of organoleptic test showed that the kimchi processed with the pickled cabbage became inferior to the conventionally made kimchi with the days of ripening.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.609-616
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• 2006

The effects of purified licorice (Glycyrrhiza uralensis) extract (PLE) as a sugar substitute on kimchi quality were evaluated by investigating acid formation, growth of lactic acid bacteria, sensory properties, and volatile odor components of PLE-added kimchi. The pH of kimchi with higher amounts of added PLE increased slightly with two or three days ripening. The acidity of unripened kimchi or kimchi ripened for one day significantly increased with addition of PLE, while that of kimchi ripened for two or three days decreased significantly (p<0.05). Addition of PLE had no significant effect on the lactic acid bacteria count of kimchi compared to that of sugar. Overall acceptability and taste of 0.005 or 0.01% PLE-added kimchi ripened for two to three days were higher than those of other samples, whereas addition of more than 0.01% PLE to kimchi unripened or ripened for one day resulted in lower overall acceptability and taste than the reference sample. Diallyl sulfide and methyl trisulfide were newly produced by ripening of kimchi, and the amounts of some volatile odor components in kimchi were also changed during ripening.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.677-680
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• 1992

For quality evaluation of Korean cabbage kimchi during fermentation at $4^{\circ}C$ for 45 days, color change of kimchi juice was measured instrumentally. Chemical analyses of the kimchi juice showed that the kimchi has reached pH 4.2 and titratable acidity of 0.63% together with the highest vitamin C content, those values being obtained under the optimum ripening period, after 30 days of fermentation. The volume of kimchi juice increased until day 30 and was constant thereafter. The CIE-1976 $L^*$$a^*$$b^*$ color values increased until day 30 and then decreased. The ratio of color value $a^*$ to $b^*$ was 0.82 in the beginning, 0.98 at the optimum ripening period, and 0.94 under the over-ripening periods. The quality of kimchi could be estimated by using the $L^*$, $a^*$, $b^*$ values or the ratio of $a^*$ to $b^*$, alone or in combination with the juice volume.