• 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.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.884-888
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• 2006

In this study, we have attempted to characterize the effects of encapsulated mustard oil with regard to the extension of the shelf life of kimchi. The quantity of mustard oil or encapsulated mustard oil added to the brined cabbage in this study was 0.05%(w/w). Overall, the fermentation processes in the encapsulated mustard oil-added kimchi (EMO) and mustard oil-added kimchi (MO) occurred at a slower rate than in the controls. The periods during which the MO and EMO kimchi samples were edible were prolonged for more than two weeks, according to measurements of pH, total acidity, and microbial changes. The overall acceptability of EMO was superior to MO throughout the entirety of the fermentation period. Sensory evaluation verified that EMO yielded a more favorable product than the MO and control varieties. Encapsulated mustard oil can be employed as a natural food additive to prolong the shelf life of kimchi, via an induced delay of the fermentation process.

• Food Science and Preservation
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• v.5 no.1
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• pp.49-56
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• 1998

The effects of the water extracts from thyme(TM) and tarragon(TG) on shelf-life and quality of kimchi were investigated by measuring the changes in pH, acidity, number of total microorganisms, number of Lactobacillii and Leuconostoc during fermentation at 1$0^{\circ}C$, and were tested for antimicrobial activities against Lactobacillus plantarum and Leuconostoc mesenteroides. TM and TG were extracted with water, ethyl ether, ethyl acetate and ethanol. Water, ethyl ether, ethyl acetate and ethanol extracts of TM showed antimicrobial activities against Lactobacillus plantarum and did not observed against Leuconostoc mesenteroides. On the other hand, water, ethyl acetate and ethanol extracts of TG showed antimicrobial activities against Leuconostoc mesenteroides and did not observed against Lactobacillus plantarum. The decrease of pH and the increase of acidity showed lower in kimchi prepared by adding water extracts from TM than in products from TG. The number of total microorganisms were also detected less in the kimchi prepared by adding water extracts from TM. And, the properties of barkless of kimchi measured instrumentally were higher for kimchi prepared by adding water extracts from TM, also maintaining good crispness. The optimal addition amounts of both TM and TG for good overall and spicy taste of kimchi were 0.03%. The results suggested the possible use of the extracts of TM and TG can be successfully used for the quality and extension of shelf-life of kimchi.

• Food Science and Preservation
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• v.2 no.2
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• pp.277-284
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• 1995

To study the shelf-life of cut cabbage kimchi, we examined the several quality characteristics of cabbage kimchi under various storage temperatures and packing materials. The pH of kimchi extracts were decreased to 4.0 in the condition of storage at 8$^{\circ}C$ during 6 days, at 4$^{\circ}C$ during 18days, 0$^{\circ}C$ during 42 days. The increase patterns of the organic acid were reverse to the changes of pH under the all conditions. The contents of reducing sugar were continuously decreased at 8$^{\circ}C$ , but increased gradually at 0$^{\circ}C$ and 4$^{\circ}C$ storage conditions. The contents of vitamine C were decreased at the early storage but increased to optimum ripening stage of pH 4.2-4.4 and after decreased continuously. The total bacterial cell counts of cabbage kimchi were increased suddenly at the early storage and after decreased gradually. And at the higher storage temperature, the more lactic acid bacteria were. On the results of sensory evaluation of cabbage kimchi at marketable shelf-life, sour taste and sour smell were significant under all experimental conditions by Duncan's multiple range test. On the above all results, we concluded that the marketable shelf-life of cut cabbage kimchi were 42 days, 19 days, 6 days at 0$^{\circ}C$, 4$^{\circ}C$, 8$^{\circ}C$ storage condition respectively.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.270-277
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• 2003

In order to enhance the firmness and shelf-life of kimchi, as well as to increase the content of well-absorbed digestible calcium, the effect of calcium lactate (CaL) treatment of salted Chinese cabbage on pH, tit ratable acidity, total microbes, lactic acid bacteria, alcohol insoluble substance (AIS) content, firmness, mineral content and tissue structure were investigated. Treatment with the Cal solution increased pH and decreased titratable acidity, which was more pronounced at higher concentrations. The edible period evaluated by pH was 7～8 days for non-treated kimchi, 10 days for 1 % treated kimchi, 15 days for 2% treated kimchi and 20 days for 3% treated kimchi. Total microbes were reduced, but lactic acid bacteria counts were higher in the treated group. CaL treated kimchi showed higher AIS content and firmer texture, which was more conspicuous in the 2 and 3% CaL treated groups. Calcium content in kimchi fermented for 15 days was 40.75～41.53 mg%, which is 42～45% higher than that in the control group. The sodium content was 23～54% less in the treated groups. The epidermis and vascular bundle tissue of kimchi fermented for 15 day was damaged more severely in the control group than in the treated group. CaL treated kimchi has a crispier taste and the development of sour taste was delayed. Therefore, addition of CaL can produces a kimchi with high calcium as well as superior texture and shelf-life, when adjusting the concentration according to the fermentation periods.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.924-931
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• 2004

A bacteriocin-producing lactic acid bacterium, which strongly inhibited the Lactobacillus plantarum recognized as an important acid spoilage microorganism in kimchi fermentation, was isolated from kimchi. From morphological, physiological, sugar fermentation, biochemical tests, and l6S rDNA sequencing results, the isolate was identified as an Enterococcus sp. and designated as Enterococcus sp. K25. The bacteriocin produced by Enterococcus sp. K25 inhibited several Gram-positive bacteria, including Lb. plantarum, whereas it did not inhibit Gram-negative bacteria and yeasts. Optimal temperature and pH for the bacteriocin production were $25^\circ{C}$ and 5.5, respectively. Enterococcus sp. K25 was applied to kimchi manufacturing alone and together with other preservatives (i.e., chitosan and fumaric acid). In addition, growth of lactic acid bacteria, pH, and titratable acidity (TA) were measured during aging at $5^\circ{C}$ and $10^\circ{C}$. Inoculation of Enterococcus sp. K25 together with fumaric acid showed the most synergistic effect on extension of kimchi shelf-life. Compared to control (no addition), the treatment prolonged the kimchi shelf-life up to 6 days, whereupon the eight-point TA value recognized as the edible limit was reached.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.932-936
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• 1995

The effect of chitosan in a salting step on the shelf-life to kimchi was investigated. Kimchi, prepared by using Chinese cabbages soaked in 10% salt solutions containing 0, 5, 10, 20 or 30% of 0.5% chitosan solution, was examined for taste and texture by sensory and instrumental evaluation during fermentation at $10^{\circ}C$ for 20 days. Sensory tests of the control kimchi revealed a strong sour taste with poor crispness and overall taste after 10 days of fermentation. In comparison, the chitosan-supplemnted kimchi, especially that reated with 20 and 30% of a chitosan solution, revealed a sour taste only after 20 days of fermentation, while still maintaining good crispness and overall taste. Properties of hardness and gumminess of kimchi measured instrumentally were higher for the chitosan-added kimchi than for the control products. This increased with increasing volumes of chitosan solution throughout the fermentation periods. These results suggest that the shelf-life of kimchi can be extended approximately 10 days using Chinese cabbage soaked in 10% salt solutions containing 20 or 30% of a 0.5% chitosan solution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.864-868
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• 1998

The studies were carried out to investigate the mixed effects of medicinal herbs, such as Lithospermum erythrorhizon and Glycyrrhiza uralensis(LG), and LG with chitosan(LGC) on shelf-life of kimchi fermented at 1$0^{\circ}C$ for 25 days. During the fermentation, pH was more slowly lowered in LG(1%, 3%) and LGC treatments than in control. Titratable acidity of these treatments was slightly lower than that of control. Viable cells of total bacteria and lactic acid bacteria in kimchi added with LG(3%) and LGC showed inhibitory effects about 1.2~1.6, 1.3~1.8 log10 cycle. The sour taste of kimchi added with LG or LGC was changed more slowly than that of control during fermentation for 5 days at 1$0^{\circ}C$. But flavor, color and overall acceptability did not show significant differences(p<0.05) among treatments. The color of kimchi added with LG was improved significantly by adding of 1% chitosan. The shelf-life of kimchi added with LGC was extended about 10 days than control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.747-753
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• 1996

This study was undertaken to enhance the shelf-fife of kimchi by heat treatment at $40~80^{\circ}C$ for Chinese cabbage during salting. Kimchi was analyzed to determine pH, titratable acidity and sensory evaluation, number of microbe and lactic acid bacteria, content of organic acid and texture. The kimchi(HT 40-kimhi) soaked with Chinese cabbage by heat treatment at $40^{\circ}C$ was enhanced the shelf-life more than that of control kimchi when evaluated by pH, titratable acidity, sour taste and overall taste. HT 40-kimchi was higher in hardness and the lowest in brittleness and gumminess and also, the content of lactic acid, number of total microbe and lactic acid bacteria were the lower than those of control kimchi. Considering all results obtained throughout these experiments, it can be concluded that the kimchi soaked with Chinese cabbage salted in heated 10% salt solution at $40^{\circ}C$ improved the quality and shelf-life of kimchi.

• Culinary science and hospitality research
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• v.10 no.4
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• pp.178-189
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• 2004

This study was performed to investigate the effects of pine pollen and horseradish, which were known as antimicrobial materials, on the fermentation of Kimchi. The physicochemical and microbial changes of Kimchi were investigated during period 30-days at $10^{\circ}C$. Even though Kimchi added pine pollen or horseradish powder were sustained the higher pH and lower acidity after 10 days, it delayed only 1∼2 more days to reach optimal value of Kimchi fermentation in experimental groups than control. The horseradish powder showed the antimicrobial effect of Kimchi at initial stage, but thereafter that effect of pine pollen or horseradish were not significant. Therefore the addition of pine pollen or horseradish powder to Kimchi is not sufficiently effective for extension of shelf-life of Kimchi.