• Journal of the Korean Society of Food Culture
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• v.11 no.2
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• pp.207-215
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• 1996

This study was carried out to find the effects of salt and other materials on the taste and fermentation of kimchi. Several parameters such as pH, acidity, salt concentration and sensory evaluation during fermentation at $20^{\circ}C\;and\;5^{\circ}C$ (after keeping at $20^{\circ}C$ for 24 hours) were used. The results are as follows: As the fermentation period increases the pH of kimchi decreases. The pH of all samples rapidly decreases to 4.2. During fermentation, the acidity at 3 hours was higher than at 5, 8 and 12 hours. For in the sensory evaluation during fermentation, kimchi salted for 5 hours showed a higher score than those salted for 3, 8 and 12 hours. During the storage period, the pH of kimchi with salted oysters rapidly decreased. A sensory evaluation done during the storage period, showed that earlier on in the storage, kimchi with salted oysters was scored higher than kimchi with other Jeotkals. The leek-added kimchi was also highly scored.

• Food Science and Preservation
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• v.23 no.2
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• pp.145-154
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• 2016

This study investigated the possibility of usage of freeze-dried ingredients for the preparation of Nabak kimchi. The quality characteristics of Nabak kimchi using freeze-dried ingredients (radish, kimchi cabbage, green onion, garlic and ginger) were monitored during storage at $4^{\circ}C$. The initial pH of Nabak kimchi was 5.76~5.93, however, it decreased significantly over increasing storage periods (p<0.05). The titratable acidity of Nabak kimchi increased during storage, reaching 0.43~1.08%. Among the freeze-dried samples, those treated with freeze-dried radish and minor ingredients showed lower titratable acidity than that of the control. The initial number of total aerobic and lactic acid bacteria were 5.57~6.25, and 5.52~6.24 log CFU/g, respectively. After 28 days, the population of total aerobic and lactic acid bacteria in the raw ingredients and freeze-dried minor ingredients was less than 8.0 log CFU/g, but more than 9.0 log CFU/g in other samples. Yeasts and molds in Nabak kimchi were detected up to 2~3 log CFU/g, but coliforms were not detected in all samples during storage. The score of firmness and overall acceptability in the control, raw ingredients and freeze-dried minor ingredients were significantly higher than others (p<0.05). These results indicated that freeze-dried ingredients, such as green onion, garlic, and ginger, can be used in kimchi and would delay microbial growth and extend the shelf-life of kimchi without any deduction of sensory quality.

• Food Science of Animal Resources
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• v.31 no.6
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• pp.899-906
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• 2011

The objectives of this study were to apply the Baranyi model to predict the growth of natural microflora in liver sausage with added kimchi powder. Kimchi powder was added to the meat products at 0, 1, 2, and 3% levels. To determine and quantify the natural microflora in the meat products, total plate counts and counts of anaerobic bacteria and lactic acid bacteria were examined throughout the 28 d of storage. The obtained data were applied to the Baranyi growth model. The indices used for comparing predicted and observed data were $B_f$, $A_f$, root mean square error (RMSE), and $R^2$. Twelve predictive models were characterized by a high $R^2$ and small RMSE. The Baranyi model was useful in predicting natural microflora levels in these meat products with added kimchi powder during storage.

• Food Science and Preservation
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• v.22 no.5
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• pp.758-767
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• 2015

Red pepper powder sensitive to aflatoxins contamination is major ingredients of kimchi. This study was conducted to investigate the effect of lactic acid bacteria (LAB) on the changes in aflatoxin levels during kimchi fermentation. Baechu kimchi was contaminated with aflatoxins ($B_1$, $B_2$, $G_1$, and $G_2$) and inoculated with LAB (Lactobacillus plantarum and Leuconostoc mesenteroides), and the following characteristics were investigated for 8 weeks: pH, titratable acidity, salinity, microbial properties, and aflatoxin levels. The pH decreased rapidly during storage, and the titratable acidity was increased. The salinity of the samples was shown to increase from 2.30 to 2.40%. The total number of aerobic bacteria and lactic acid bacteria in kimchi inoculated with LAB was significantly higher than that of the others. Yeast and molds were detected at approximately 1~3 log CFU/g during storage. Coliforms were detected in the control after 4 weeks, whereas in other samples they were not detected until after 2 weeks. The aflatoxin levels reduced during kimchi fermentation. The average reduction rate of aflatoxin levels during kimchi fermentation was 8.39%, but in kimchi inoculated with Lac. plantarum and Leu. mesenteroides, the rate were 25.16 % and 27.86%, respectively. These results showed that aflatoxins can be removed by LAB during kimchi fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.239-244
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• 2008

Paprika oleoresin (PO) and artificial Kimchi flavor (AKF) were added to Kimchi to improve the sensory qualities deteriorated by gamma irradiation in terms of color and flavor. Optimum concentration of both PO and AKF resulting from the sensory evaluation was 0.2%. The redness and capsanthin contents of Kimchi decreased by gamma irradiation at 25 kGy during storage at $35^{\circ}C$. However, the redness and capsanthin contents of gamma-irradiated Kimchi was increased by the addition of 0.2% PO, and maintained during the storage at $35^{\circ}C$ for 30 days. The result from the sensory evaluation indicated that sensory qualities of gamma-irradiated Kimchi were effectively improved by the addition of PO and AKF during storage at $35^{\circ}C$. Therefore, the combined treatment of additives (PO and AKF) and gamma irradiation can be considered as an effective method to improve the redness and sensory qualities of Kimchi sterilized by high-dose gamma irradiation.

• Journal of Food Hygiene and Safety
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• v.3 no.4
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• pp.225-232
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• 1988

To improve the storage method for Kimchi, optimal ripening Kimchi was irradiated with doses of 1,3,5 kGy Co-GO gamma radiation, followed by the microbiological, physicochemical and sensory evaluations during storage at $5^{\circ}C$. 1. Total aerobic count increased in the beginning of storage and then decreased slowly as the number of total lactobacilli (anaerobe) increased. The above total aerobic and lactobacilli were reduced by 1 to 3 log cycles with irradiation and at the 90th day after storage the number of total lactobacilli remained $1.30{\times}10^{8}\;per\;ml$ in3 kGy irradiated group. Irradiation treatment at 3 kGy sterilized coli forms and molds contaminating the sample as the level of $2.0{\times}10^{4}\;per\;ml\;and\;5.4{\times}10^{2}\;per\;ml$, respectively and no apparent growth was observed in both control and 1 kGy irradiated groups after 20 days of storage. The population.of yeast, $3.5{\times}10^{3}\;per\;ml$ initially, in, creased steadily during Kimchi storage and at 90 days of storage the number was shown to be $5.6{\times}10^{4}\;per\;ml\;and\;6.5{\times}10^{2}\;per\;ml$ in control and 3 kGy irradiated groups, respectively. 2. In the physicochemical changes during Kimchi storage, pH, acidity and volatile acid of non-irradiated control at the 45th day after storage were 4.0,0.7% and 0.066%, while those of 3 kGy irradiated group were 4.2, 0.59 and 0.06% at the 90th day of storage, respectively. The reducing sugar content of all stored samples changed inversely total acidity content, indicating irradiation delayed the changes of them. The amount of aseorbic acid decreased gradually with the storage time and irradiation dose increase. Textural parameters of 3 kGy irradiated group were superior to those of other groups at the latter stage of storage. 3. Sensory evaluations showed that 3 kGy irradiation was the optimum dose level to extend tite shelf-life of Kimchi more than two months as compared to control.

• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.609-614
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• 2006

Quality changes in mustard leaf kimchi were investigated during storage for 60 days at $5^{\circ}C$. As the storage period changed from 0 to 60 days, the pH and reducing sugar content of mustard leaf kimchi decreased, while the total acidity and hunter's color increased. The vitamin C content in mustard leaf kimchi decreased gradually from 10 to 30 days and then markedly increased after 40 days. The total dietary fiber content and antioxidative activity were significantly higher in fresh mustard leaf kimchi than in fermented kimchi. The major volatile components of mustard leaf and mustard leaf kimchi were determined to be allyl isothiocyanate, 3-butenyl isothiocyanate and phenylethyl isothiocyanate. The contents of allyl isothiocyanate and phenylethyl isothiocyanate, the two major functional components, in mustard leaf kimchi were determined to be 43.72 and $36.17\;{\mu}g/g$ dry weight basis, respectively.

• Food Science of Animal Resources
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• v.41 no.6
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• pp.950-966
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• 2021

This study investigated the effects of lemon extract powder and vinegar powder on the physicochemical and microbiological characteristics of pork sausages naturally cured using white kimchi powder during storage for 30 days. Six batches were included: control (0.01% sodium nitrite and 0.05% sodium ascorbate); treatment 1 (0.3% white kimchi powder and 0.5% lemon extract powder); treatment 2 (0.3% white kimchi powder and 1.0% lemon extract powder); treatment 3 (0.3% white kimchi powder and 0.5% vinegar powder); treatment 4 (0.3% white kimchi powder and 1.0% vinegar powder); and treatment 5 (0.3% white kimchi powder, 0.5% lemon extract powder, and 0.5% vinegar powder). Treatment 2 had significantly lower pH values and higher cooking loss than the other batches (p<0.05). Treatments 1, 2, and 5 had similar (p>0.05) CIE a^* as the control, while treatments 3 and 4 showed significantly lower values (p<0.05). The residual nitrite content in naturally cured products was lower than the control (p<0.05), while treatments 1 and 2 showed significantly higher nitrosyl hemochrome content and curing efficiency (p<0.05). TBARS values were similar for all treatments and the control (p>0.05). Treatments 1 and 2 showed significantly reduced aerobic plate counts (APC; p<0.05) than the control and other treatments. However, across all batches, TBARS values and APC significantly increased during storage (p<0.05). Our results suggest that lemon extract powder, rather than vinegar powder, may offer a promising alternative for supplementing the functions of nitrite in naturally cured sausages.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.112-118
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• 1995

The effect of various packaging methods on kimchi quality was investigated in order to develop the packaging techniques for preventing commercial kimchi products from inflation and explosion, due to fermentative gas evolved during storage and distribution. Kimchi was packaged in different methods; 1) atmospheric packaging(AP), 2) check valve packaging(CV), 3) double packaging(DP), and 4) vacuum packaging(VP). The quality of kimchi during storage at $10^{\circ}C$ was evaluated in terms of gas composition, free volume, pH, titratable acidity color index and sensory properties. The gas composition inside packages showed different curves according to the packaging methods. Due to fermentative gas accumulation in both AP and CV, $CO_2$ concentration increased by 2 stepwise pattern, while $O_2$, concentration decreased exponentially. In DP, $O_2$ concentration remained constant, but $CO_2$ concentration increased by 2 stepwise pattern and then decreased. In contrast, VP produced low $O_2$ and high $CO_2$ concentrations only at the end of storage. The free volume in both AP and CV showed typical sigmoidal curves similar to $CO_2$ concentration changes. It remained constant in DP, but started to increase at the late stage of storage in VP. There was no significant effect of packaging methods on pH changes of kimchi. In titratable acidity, DP maintained relatively higher than others. Regarding to the color change of crushed kimchi juice in all packages, L and b values decreased exponentially but a value remained constant during storage. Color index(L b/a) of crushed kimchi juice decreased exponentially and remained constant at the end of storage. The growth of lactic acid bacteria was VP, CV, AP, DP in increasing order. In sensory test, the sourness scores of DP were fairly higher than those of others, but the texture was not significantly affected by the packaging methods. The preference for kimchi showed VP>AP, CV>DP in order of score. In this study, it could be proposed to employ DP and VP method as the effective packaging techniques for preventing commercial kimchi products from inflation.

• 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.