• 한국식생활문화학회지
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• 제25권5호
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• pp.607-614
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• 2010

Changes in major volatile odor components (VOC) and sensory properties of kimchi during ripening for 4 days were investigated, and major VOCs of the raw materials of kimchi were also analyzed. Seven of eight major VOCs of kimchi originated mainly from garlic, while one originated from ginger. During 4 days of kimchi ripening, the amount of ethanol, which was substantially higher than that of other VOCs, increased continuously but decreased slightly on the fourth day. The amount of diallyl disulfide decreased during ripening, while that of allyl mercaptan decreased on the first day and increased slightly thereafter. The amount of methyl allyl sulfide, diallyl sulfide, and methyl trisulfide increased continuously during ripening, while that of dimethyl disulfide and methyl propyl disulfide increased until the second day and decreased thereafter. Scores of overall acceptability, taste, and odor for kimchi ripened for 2 days were significantly higher than those of other samples (p<0.05). The correlation between scores of overall acceptability and the amount of dimethyl disulfide or methyl propyl disulfide was higher than that of other VOCs.

• 한국포장학회지
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• 제26권2호
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• pp.71-76
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• 2020

CO₂ concentration in kimchi package has emerged recently as a potential index of product ripening to be monitored or sensed in intelligent packaging. Considering that addition of CO₂ absorber into the flexible kimchi package changes behavior of its CO₂ concentration, ripening of kimchi in total acidity, package CO₂ concentration in partial pressure (P_CO2) and package volume at 10℃ were estimated by mathematical model for two size packages included with different CO₂ absorbers. In small size package containing 0.5 kg of kimchi, relatively less gas permeable low density polyethylene (LDPE) sachet of the absorber was found to give rise of P_CO2 linearly correlated with acidity at acceptable conditions of absorber amount and size. The levels of P_CO2 at optimum ripening were different with absorber amount. However, highly gas permeable microporous spunbonded film (Tyvek) sachet did not show the linear relationship except a condition of 1.5 g of CO₂ absorbent. In large size package containing 2.0 kg, absorber sachets of LDPE and Tyvek could give the linear relationship between product acidity and package P_CO2 but at different levels (P_CO2 of package with LDPE sachet: 0.46~0.79 bar, P_CO2 of package with Tyvek sachet: 0.00~0.75 bar). The P_CO2 at optimal ripening was found to be less variable with LDPE sachets than with Tyvek ones. Use of package CO₂ concentration as an indicator of kimchi ripening was shown to be possible on the limited conditions where the linear relationship between them is established or confirmed.

• 한국수산과학회지
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• 제43권5호
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• pp.415-420
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• 2010

In Korea, oysters are used as an ingredient of Kimchi (Korean pickled cabbage) in early winter. Although viral contamination of oysters, including contamination by norovirus, can provoke gastroenteric illness, little is known of the epidemiological relationship to outbreaks. We postulated that Kimchi ripening can reduce the infectivity of norovirus, in order to test this hypothesis, we carried out a model experiment. Since norovirus is currently regarded as non-culturable, feline calicivirus (FCV) was used as a surrogate to examine the activation of norovirus with Kimchi ripening. In commercial well-prepared Kimchi, the infectivity ($TCID_{50}$) of FCV decreased by 2 log every 12 hours and reached the limit of detection after 48 hours during over-aging at $25^{\circ}C$. During storage at $4^{\circ}C$, the infectivity ($TCID_{50}$) of FCV decreased slowly and reached 5.00 $TCID_{50}$ after 48 hours. The low pH appears to affect the infectivity of FCV directly via organic acids produced by ripening during over-aging and storage. In neutralized lab-prepared Kimchi (pH 7.0), the infectivity ($TCID_{50}$) of FCV also decreased and reached the limit of detection after 72 hours at $4^{\circ}C$. This indicates that there are substances beside organic acids in Kimchi that originate from the raw materials and are produced during ripening. Among the raw materials, salt-fermented anchovies and garlic showed high direct antiviral activity. The main factor decreasing the infectivity of FCV in Kimchi was the high acidity caused by organic acids, regardless of the type, produced by ripening. Furthermore, unknown secondary products of microorganisms associated with Kimchi ripening and antiviral materials originating from raw material might contribute to the decreased infectivity of FCV, the surrogate of norovirus.

• 한국식품영양과학회지
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• 제21권2호
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• pp.163-170
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• 1992

김치의 숙성도를 평가하기 위한 한 방법으로 김치의 숙성과정 중 자연적으로 유출되는 김치액의 색상 변화를 색차계를 이용해서 측정하고, 또한 이들 결과를 성분분석과 관능적인 평가와 비교 조사하였다. 성분분석과 관능검사 결과는, 16$^{\circ}C$에서 숙성 3일째 김치의 숙성 적기 pH인 4.3에 달하였으며 이때 비타민 C 및 carotenoids 함량도 거의 최고치에 달하고 신맛과 조직감도 적당하였다. 숙성온도 4$^{\circ}C$에서는 숙성 6일후에도 미숙단계에 있었다. 숙성온도 16$^{\circ}C$에서 김치액의 $L^{*}$ 값은 숙성기간 중 뚜렷한 변화를 나타내지 않았다. 반면 $a^{*}$ 값은 숙성 4일까지는 상승하다가 이후 급속히 감소하였으며 $b^{*}$ 값은 숙성 3일까지는 증가하다가 그후 거의 변화가 없었다. 김치액량, pH 및 산도는 김치액의 $L^{*}$ 혹은 $b^{*}$ 값과, carotenoids 함량은 다만 $a^{*}$ 값과 높은 상관관계를 나타냈다. 김치액의 색상으로 김치의 숙성 정도를 평가하기 위해서는 $a^{*}$ 혹은 $b^{*}$ 간을 지표로 삼는 것이 바람직하였다. 즉, $a^{*}$ 값이 담금 초기와 비교해서 동등 혹은 낮은 값을 나타내거나 $b^{*}$ 값이 거의 변화가 없을 때는 과숙기에 이르렀다고 할 수 있었다. 김치의 적숙기를 예측하는 한 방법으로 $a^{*}$ 와 $b^{*}$ 의 비( $a^{*}$ / $b^{*}$ )를 이용할 수 있었다. 즉, $a^{*}$ / $b^{*}$ 의 비값이 1이상 흑은 1에 가까울 때는 미숙기, 0.8 부근 일때는 적숙기, 0.8보다 작아 질수록 적숙기에서 과숙기로 점차 옮아감을 알 수 있었다.

• 한국식품조리과학회지
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• 제17권5호
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• pp.483-489
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• 2001

본 연구의 목적은 김치의 장기간 저장숙성이 김치 또는 동결건조/복원 제품의 품질에 미치는 영향을 조사하는 것이다. 김치를 $0^{\circ}C$에 120일간 숙성시키면서 10일 간격으로 일정량씩 취하여 동결건조한 후 복원하여 젖산균수, pH, 전단력, 관능적 특성 및 형태를 관찰하고, 동일한 조건하에서 숙성된 김치의 품질과 비교하였다. (1) $0^{\circ}C$에서 120일간 숙성시킨 김치(Raw시료)의 젖산균수는 다소 감소하는 경향을 보였으며, pH는 점차 저하하였다. 이러한 경향은 F/D시료의 경우도 유사하였으며, 젖산균수가 동결건조에 의하여 Raw시료의 6~l6%로 감소하였다. (2) 120일의 숙성으로 김치시료의 전단력은 영향을 받지 않았으나 동결건조에 의하여 김치의 전단력이 현저하게 증가하였다. (3) 120일의 숙성기간 동안에 Raw시료와 F/D시료의 전반적인 기호성과 맛은 변화, 즉 저하하였으나, 저하하는 정도는 Raw시료의 경우가 F/D시료의 경우보다 다소 높았다. Raw시료와 F/D시료의 냄새는 120일의 숙성기간 동안에 저하하였으나 70일 이후에는 두 시료 사이의 차이가 그다지 크지 않았다. Raw시료와 F/D시료의 Moistness는 120일의 숙성기간 동안에 비교적 일정한 수준을 유지하였다. Raw시료의 저작성은 120일의 숙성기간 동안에 저하하였으나 F/D시료는 120일의 숙성에 의하여 큰 영향을 받지 않았다. Raw시료와 F/D시료의 색상은 120일의 숙성기간 동안에 변화하였으나 두 시료 사이의 차이는 크지 않았다. 이상의 결과로부터 얻은 결론은 다음과 같다. 즉, 김치를 120일간 숙성하면서 동결건조한 시료(F/D시료)와 숙성만 시킨 시료(Raw시료)를 비교하여 볼 때, 장기간의 숙성에 의하여 두 시료의 젖산균수, pH, 전단력이 변화하는 경향은 큰 차이가 없었으나 관능적 특성, 특히 전반적인 기호성, 맛, 저작성이 변화하는 경향은 두 시료 사이에 차이가 있는 것으로 생각된다.

• 한국환경보건학회지
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• 제31권1호
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• pp.79-85
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• 2005

This study was undertaken to investigate the changes of index microorganisms and lactic acid bacteria of traditional Korean fermented vegetables (kimchi) during the ripening and fermentation period. A type of kimchi, baechoo-kimchi, was prepared and stored at $10^{\circ}C$ for 8 days. The numbers of the total aerobic bacteria, psychrotrophilic bacteria, coliform bacteria, and Escherichia coli in the kimchi and also in raw materials of the kimchi (Chinese cabbage, green onion, ginger, garlic, and red pepper) were counted using appropriate media. The highest number of aerobic bacteria was detected from ginger, then red pepper, then garlic, then Chinese cabbage, and lowest number from green onion. The highest number of psychrotrophilic bacteria was detected from red pepper, then Chinese cabbage, then garlic, then ginger, and the lowest number from green onion. Coliforms and E. coli were not detected from all of the raw materials of kimchi. Total aerobic bacteria and lactic acid bacteria of the kimchi showed gradually increasing during ripening and fermentation. The number of psychrotrophilic bacteria showed a similar level in the kimchi. Coliform bacteria were detected at the 3rd, 4th, and 5th day of the kimchi fermentation period, although they were not detected from the raw materials of the kimchi. However, the bacteria were not detected in the kimchi after 6 days. E. coli was not detected in all kimchi samples. The pH value of the kimchi gradually decreased, and acidity increased over fermentation period. This study indicates that there was contamination of coliform bacteria during the process of kimchi preparation, and lactic acid bacteria proliferated in the kimchi during fermentation inhibited the growth of coliforms. More research is needed to evaluate the inhibitory effects of each raw materials of kimchi.

• 한국식품영양과학회지
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• 제23권2호
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• pp.274-278
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• 1994

Correlation between pH and color of Kimchi during fermentation was investigated to visually evaluate the fermentation degree of Chinese cabbage Kimchi. Color "a" and 'H" values in the white part, "a", "H" and "C" values in the green part of the Kimchi showed a high correlation with pH, respectively. "a" and "H" values of Kimchi juice. "L" and "V" values of red pepper attached to kimchi had a high correlation with pH. The color of the white part was light greenish white in unripended Kimchi, but changed to redish in ripended kimchi. Green part changed from light green to redish green as ripening. Red pepper powder attached to kimchi showed redish color in unripening, but changed to yellowish re din over ripening.

• 한국환경보건학회지
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• 제34권1호
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• pp.70-75
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• 2008

The Chinese cabbage kimchi, baechoo-kimchi, is the most popular type of kimchi in Korea. This study was performed to investigate the changes of index microorganisms (aerobic bacteria, psychrotrophilic bacteria, coliforms, and Escherichia coli), lactic acid bacteria, pH, and acidity of kimchi during the long-term fermentation and ripening. A homemade-style traditional Korean baechoo-kimchi, was prepared from Chinese cabbage, red pepper, green onion, garlic, ginger, and salt-fermented anchovy sauce, and then incubated at $10^{\circ}C$ for 28 days. In the baechoo-kimchi, the number of aerobic bacteria increased with time. The number of psychrotrophilic bacteria maintained their numbers $(10^4CFU/g)$ in the kimchi during the fermentation. Coliforms and E. coli were not detected in the kimchi. The pH of kimchi decreased and the acidity of kimchi increased over time. Lactic acid bacteria, which are representative of fermentative microorganisms in the kimchi process showed rapid growth in the earlier stage of fermentation and increased steadily after 7 days. The counts of lactic acid bacteria were at a level of $10^4CFU/g$ early in the fermentation stage, reaching a level of $10^8CFU/g$ after 14 days, and at this point pH was 4.18 and acidity reached 0.63, indicating that the optimal state of kimchi fermentation. This study suggests that the lactic acid bacteria which were proliferated in kimchi during the ripening and fermentation could contribute to improving the taste and flavor of kimchi and inhibit the growth of pathogenic microorganisms that might exist in kimchi.

• 동아시아식생활학회지
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• 제17권4호
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• pp.511-519
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• 2007

This study was conducted to estimate the drift of change for kimchi purchase, and to contribute to quality improvement of kimchi sold at markets. Questionnaries were distributed to 450 adults and 396 were statistically analyzed. The methods used to analyze the items were frequency analysis, Chi-square, t-tests and ANOVA. The highest preference for kinds of kimchi was Beachoo kimchi, while the preference for Nabak kimchi was low. In terms of the degree of ripening, most subjects preferred properly ripened kimchi. With regard to the purchase amount the subjects preferred 1 kg and mainly purchased it once every three months at large market and supermarkets. The main reason for purchasing kimchi at markets was 'convenience', while the reason they didn't purchase it was 'it might contain artificial seasoning'. With regard to the development and improvement of the kimchi industry, the subjects belived that taste and ripening should be standardized, and that kimchi should be treated sanitarily. They acknowledged that kimchi products should be diversified, and active marketing should be carried out in order for it to be globalized.

• Food Science and Biotechnology
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• 제14권3호
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• pp.358-362
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• 2005

Eudragit E100 microcapsules containing nisin were prepared and employed to control the ripening of kimchi. The recovery yields of microcapsules without/with nisin ranged from 93.53 to 94.61 % and 92.85 to 94.09 %, respectively. The particle size of microcapsules decreased (>200 to $100\;{\mu}m$) as the amount of aluminium tristearate increased from 6.0 to 15 %. The microcapsules were morphologically spherical and possessed rough surface. Nisin was completely released from the microcapsules within a day at pH 3.0 and within two days at pH 4.0, 5.0, and 6.0, respectively, whereas half the amount of nisin was released at pH 7.0 within two days. During fermentation of kimchi with microcapsules containing nisin, the pH decrease was retarded which resulted in a constant pH of approximately 4.2. The pH of 4.2 was optimal for ripening of kimchi for a longer period of time when compared with samples without nisin.