• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.575-581
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• 1997

This study was examined in the physical and sensory characteristics of Dongchimi when ginseng and pineneedle added with 0.1 and 0.3% respectively Dongchimi was at room temperature for first day and at 4$^{\circ}C$ from End to 28th day. Titratable acidity of Dongchimi was increased during 29 days of fermentation, and pH was decreased gradually during fermentation. The viscosity and turbidity were slowly increased in all Dongchimi during fermentation. The Hunter's ‘L’values lowered gradually after 22th day of fermentation however ‘a’values decreased but ‘b’values increased after 15th day of fermentation. Dongchimi added with pineneedle and ginseng showed higher scores for carbonate flavor, sour taste, fresh-taste and color than those of non-treated Dongchimi. Dongchimi added with ginseng had lower sensory evaluation scores than those of others.

• Food Science and Preservation
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• v.16 no.4
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• pp.482-489
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• 2009

We investigated how supercritical $CO_2$ affected sterilization and enzyme inactivation in dongchimi, a conventional Korean fermented food. The growth of bacteria, including lactic acid bacteria, in dongchimi juice tended to decrease with increased pressure and temperature during treatment with supercritical $CO_2$. D values were affected by pressure more than by temperature. The lowest total number of cells and D values of lactic acid bacteria were observed after treatment with supercritical $CO_2$ at 25 MPa and $25^{\circ}C$; these conditions also reduced polygalacturonase activity in radishes by approximately 40.3%. Supercritical $CO_2$ can be used as an alternative method of sterilization and enzyme inactivation, minimizing sensory loss and textural changes in vegetable materials.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.596-601
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• 1998

Effects of high hydrostatic pressure on microorganisms, pectin enzymes and texture of dongchimi (pickled radish roots) were investigated. Dongchimi was pressurized at $200{\sim}686\;MPa$ for 5 min when its pH reached to 4.0. Total aerobes, initial concentration of $4.05{\times}10^8\;CFU/mL$, were completely inactivated by high hydrostatic pressure at 600 MPa. Lactic acid bacteria, yeasts and molds, initial concentration of $3.25{\times}10^8\;CFU/mL\;and\;3.55{\times}10^4\;CFU/mL$, respectively, were completely inactivated by high hydrostatic pressure at 400 MPa. Leuconostoc mesenteroides appeared to be the most barotolerant lactic acid bacteria because it was the sole bacteria survived at 380 MPa. Pectinesterase (PE) and polygalacturonase (PG) activities increased after high hydrostatic pressure treatment. Residual PE activity was 193 after pressurization at 500 MPa, and residual PG activity was 191 after pressurization at 686 MPa when the initial enzyme activity of control was set to 100. The hardness of pressurized dongchimi was higher than control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.167-174
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• 2003

Physicochemical and sensory properties of turnip dongchimi were examined during fermentation at $0^{\circ}C$. Salt concentrations of dongchimi liquid were around 1.3% during fermentation. Greater decrease in pH and reducing sugar content in solid, and higher increase of acidity, turbidity and reducing sugar content in liquid were observed during fermentation. The acidity and pH at the optimal fermentation time, at the day 40 was observed 0.36% and pH 3.9, respectively Lactobacilli number, turbidity, anthocyanin content, the Hunter color L and a values were the greatest at the day 40 and then gradually decreased. The hardness and fracturability of turnip, determined by texture analyser, decreased during fermentation, while springiness increased. Sensory evaluation showed that the scores of color of purple, sweet taste, savory taste, and over-all preference of dongchimi were highest at the day 40. Score of overall preference of turnip dongchimi was the highest with 6.5 at the 40th day of fermentation, the optimum fermentation time, but the score until the day 60 was not significantly decreased.

• Korean Journal of Food Science and Technology
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• v.2 no.2
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• pp.34-37
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• 1970

The variation of acidity, pH and oxidation-reduction potentials of Dongchimi (a kind of large raddish pickle) during its fermentation was investigated. Estimation of oxidation-reduction potentials was carried out by the electric method. 1. Acidity was increased-3.5% by lactic acid and pH was decreased 3.4 during Dongchimi fermentation. 2. In Dongchimi, oxidation-reduction potentials was comparatively high (rH above 10) in the earlier stage and then decreased rapidly from rH 15 to 2.0 but slightly increased rH 5.0 in the later stage of the fermentation. 3. It is suggested that the earlier stage of fermentation was more aerobic condition than the later stage.

• Food Science and Preservation
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• v.10 no.4
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• pp.554-559
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• 2003

The optimal culture conditions on bacteriocin producing of Lactobacillus sp. FF-3 isolated from Korean Dongchimi, were studied for enhancing its production with regard to environmental and nutritional factors. The optimal cultivation time, initial pH and temperature were 21 hours, pH 7.0 and 30∼37$^{\circ}C$ respectively. Optimal compositions of culture medium for bacteriocin production were glucose 3% as carbon source, tryptone 4% as nitrogen source, and manganese sulfate 0.005% as inorganic salt with other basal components. The maximum antimicrobial activity was 484 BU/mL under the optimal culture condition.

• Food Science and Preservation
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• v.10 no.3
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• pp.406-410
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• 2003

For selection of lactic acid bacteria for probiotics, we have examined isolated strains from Korean Dongchimi to assess the acid, bile, and pancreatic tolerance and the growth inhibition on the pathogens. Especially, a kind of isolated strains, FF-3 showed the highest resistancy to both of HCl and bile salt, as well as the highest inhibitory activities against Salmonella sp. and Escherichia coli. Further the bacteriocin of FF-3 showed relatively wide range of inhibition spectrum against gram positive and some gram negative bacterias. By using 16s rDNA sequencing method, FF-3 of the selected lactic acid bacteria were found to be identified as genus Lactobacillus.

• Journal of the Korean Society of Food Culture
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• v.20 no.5
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• pp.508-515
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• 2005

The effect of glue plant(Codium fragile) on the Dongchimi fermentation was investigated by measuring physicochemical properties during fermentation at $10^{\circ}C$. Dongchimi was prepared with various levels(0, 0.5, 1.0 and 1.5%) of glue plant(Codium fragile). The pH of Dongchimi decreased slowly in all samples during fermentation. Total acidity of Dongchimi increased gradually during fermentation and total acidity of Dongchimi with glue plant(Codium fragile) was higher than that of control. Redox potentials decreased until 30 days of fermentation but increased thereafter. Reducing sugar content increased in the initial stage of the fermentation periods, and then decreased gradually. The reducing sugar content of Dongchimi with glue plant(Codium fragile) was higher than that of control. The content of total vitamin C was much higher in dongchimi with glue plant(Codium fragile). In color measurement, lightness value decreased gradually. However, redness and yellowness values increased gradually during fermentation but decreased thereafter. The content of hot water soluble pectin(HWSP) decreased as the fermentation proceeded, but the content of hydrochloric acid soluble pectin(HClSP) and sodium hexametaphosphate soluble pectin(NaSP) increased.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.602-607
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• 1998

Changes in microbial count, enzyme, texture and color during storage of dongchimi (pickled radish roots) were investigated. Dongchimi was pressurized at 400 MPa for 5 min. Pressurized dongchimi stored at $4^{\circ}C\;(PS4)\;and\;37^{\circ}C\;(PS37)$ were compared with control $(stored\;at\;4^{\circ}C)$. PS4 and PS37 maintained their initial pH values during storage. Lactic acid bacteria, yeast and mold were not detected during storage in pressurized dongchimi. Pectinesterase, polygalacturonase activities and hardness of pressurized dongchimi decreased during storage. PS4 maintained its hardness longer than both control and PS37 during storage. The yellowness of PS37 was too high compared to control and PS4, indicating that storage of pressurized dongchimi at $37^{\circ}C$ was undesirable.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.267-271
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• 1991

The chemical and organoleptic properties of dongchimi studied for their changes during fermentation at $4{\sim}35^{\circ}C$ in 7% NaCl solution with seasonings. It was found that pH decrease showed three variation points in its slope at about pH 5.2, 4.7 and 4.1 during fermentation. A negative linear relationship between total acidity and logarithmic value of pH was obtained. The slope of the relationship curve was increased as the fermentation temperature increased. The reducing sugar was increased until pH reached$4.0{\sim}4.2$ followed by a small decrease and its amount was lowered as the temperature increased from $4\;to\;25^{\circ}C$ The major nonvolatile organic acids were lactic and citric acids. The increase in lactic acid were more marked at $25^{\circ}C$ than at $4^{\circ}C$. As fermentation proceeded the fresh radish odor significantly decreased while sourness and yeast-moldy odor increased. The crispness of the radish decreased slightly during fermentation.