The Chinese Sigyeong records the foods of the Primitive Pickling Period, pickling being a universal vegetable storage method, but does not indicate the origin of the pickled vegetables or the location of the source of transmission. Kimchi mainly used salt and sauce-based soaking materials at the beginning of the Fermented Pickling Period (beginning in the 1st to 3rd centuries A.D.), and it differed from the Chinese method, which used alcohol and vinegar. In the Umami-Flavored Pickling Period (beginning in the 14th and 15th centuries A.D.), jeotgal, fermented seafoods, were added, and pickles with a completely new identity were created, one different from any other pickles in the world. Lastly, entering the Complex Fermentation and Pickling Period (beginning in the 17th and 18th centuries), the technical process evolved using a separate special seasoning containing red pepper as the secondary immersion source after pickling in brine, the primary immersion source. As a result of this, kimchi was transformed into a food with a unique form and taste not found anywhere else. The unique characteristic of kimchi is that the composition of original materials, a combination of salted marine life and vegetable ingredients, is its core identity, and there is a methodological difference in that it is completed through a second process called saesaengchae (生菜)-chimchae (沈菜).

In this study, we investigated the effects of cooling rate during storage on spring kimchi cabbage from an economic perspective. For long-term storage, kimchi cabbage (KC) should be maintained at a low temperature immediately after harvest; however, a sudden change in temperature during storage may lead to chilling injury in KC. The optimal cooling rate is important for the long-term storage of KC. To identify the optimal cooling rate, KC was cooled at different cooling rates (1oC, 2oC, 4oC, 6oC, 8oC, and 24 oC/day), and then stored at 1oC for 90 days. Thereafter, weight, trimming, total loss, pH, free sugar content, and total bacterial count changes were measured. Spring KC stored at the cooling rate of 6 oC/day presented a lower total loss and better sensory properties than KC stored at other cooling rates; thus, 6 oC/day is an appropriate cooling rate for long-term storage of KC.

배추 재배시기에 따른 품질특성을 비교하기 위해 월별 배추의 생육특성과 이화학특성, 미생물 특성을 분석하고 군집분석을 수행하였다. 군집특성은 5-6월(I), 7월과 10월 (II), 8-9월(III), 11-12월과 1월(IV), 2-4월(V) 총 5그룹으로 분류되는데 이는 배추 작형과도 대부분 일치되었다. 주성분 분석을 통한 그룹별 특성의 경우 I 그룹은 미생물 수, II와 III 그룹은 수분함량, IV, V 그룹은 구중과 유리당 함량이 높은 것으로 분석되었다. 배추 품질특성에서 높은 상관관계를 보이는 항목은 구중과 결구율, 고형분 함량과 유리당 함량이었고, 고형분 함량과 유리당 함량을 회귀식으로 나타내면 Y(유리당) = 0.8195X(고형분 함량) - 1.2451로 나타낼 수 있는데 이를 활용해 배추의 고형분 함량으로 유리당 함량을 추정할 수 있을 것으로 판단된다. 본 연구를 통한 월별 배추의 품질특성은 해당 시기에 김치를 제조할 때 기초자료로 활용할 수 있을 것으로 기대된다.

Ammonium (NH4 +-N) and nitrate-nitrogen (NO3-N) fertilizers were spread 30 kg/10a and 60 kg/10a, respectively, as additional fertilizers in nitrogen fertilization to investigate their effects on spring kimchi cabbage's physiological disorders during cold storage. The initial weight of spring kimchi cabbage after harvesting was 3.80 kg with two-fold NO3-N, whereas it was 3.22 kg with one-fold NO3-N. After 90 days of cold storage, the total loss ratio became lower as the nitrogen fertilizer ratio increased. The pH increased, reducing sugar content decrease during the storage. Black speck occurrence became higher as the nitrogen fertilizer increased. Mid-rib brown stain and soft rot were observed slightly in kimchi cabbage regardless of the nitrogen fertilizer ratio. Two-fold NO3-N fertilization showed a positive effect on increasing weight and reducing kimchi cabbage loss, but it exhibited a negative effect on the black speck. The method and content of nitrogen fertilization of spring kimchi cabbage may be adjusted according to the usage and storage periods.

본 연구에서는 유산균에 의한 검은콩의 최적 발효조건을 확립하고 발효된 검은콩의 품질특성을 평가하였다. 가정에서 제조된 배추김치로부터 분리한 Lactobacillus plantarum SU22는 병원성 세균에 대해 강한 항균 활성을 보였고 생체 아민과 발암성 효소인 β-glucuronidase를 생성하지 않았기 때문에 검은콩 발효의 스타터로 선정되었다. 검은콩은 5 kgf/cm2, 150oC로 조절된 팽화기에서 10분 동안 팽화 처리한 것과 처리하지 않은 것으로 각각 10- 30% 혼합액을 만들고 L. plantarum SU22를 1%(v/v) 접종하여 37oC로 48시간 동안 진탕 배양하면서 유산균의 생육 특성을 비교하였다. 유산균의 생균수는 L. plantarum SU22 로 발효된 팽화 검은콩(20%) 배양액에서 9 Log CFU/mL 이상이었다. 20% 팽화 검은콩 배양액을 alcalase로 가수분 해한 후 L. plantarum SU22로 발효하는 것이 최적 조건인 것으로 밝혀졌으며 유산균의 생균수가 10.30 Log CFU/ mL까지 증가하였다. 최적 조건에서 총 폴리페놀 함량(94.02 mg GAE/g)과 DPPH 라디칼 소거능(92.50%)이 비 발효 대조군(87.74 mg GAE/g, 83.14%)에 비해 현저하게 증가하였다(P<0.05). 결론적으로 검은콩을 팽화한 후 alcalase 처리와 L. plantarum SU22를 병행하여 발효할 때 바이오제닉 아민이 없는 검은콩 발효액을 효과적으로 제조할 수 있으며, 총 폴리페놀과 DPPH 라디칼 소거능을 유의적으로 증가시킬 수 있다는 것을 알 수 있었다.

본 연구는 스트렙토조토신에 의해 유도한 당뇨병, 알코올성 간 손상 실험용 랫드에서 혈액 지질 감소, 당뇨병 및 알코올성 간 손상 예방에 미치는 지장김치 추출물의 경구투여 효과를 조사하였다. 당뇨병 모델동물에서, 혈액 지질 프로파일, ALT, AST 수준은 DC (당뇨병 대조군)와 비교할 때 김치추출물 투여군에서 낮아졌으며 혈당은 DCJK (DC+지장김치 추출물 경구투여군)가 DCCK (DC+일반김치 추출물 경구투여군)에 비해 낮았다. 인슐린 수준은 NC (정상대조군), DCJK > DCCK > DC 순서로 높게 나타났다. 알코올성 간 손상 모델동물에서, 혈액 ALT, AST, 빌리루빈 농도는 AC (알코올 대조군, 일일 소주 1병 섭취군) > ACCK (AC+일반김치 추출물 경구투여군) > ACJK (AC+지장김치 추출물 경 구투여군) > NC 순서로 낮았다. 간 조직의 임상병리학적 소견은 AC에서 가장 심각한 손상을 보였으나 소주1병과 김치 추출물 특히, 지장김치 추출물 경구투여군은 일반김치 추출물 경구투여군에 비해서 회복되는 속도가 개선되었다. 결과는 당뇨병 및 알코올성 간 손상 모델동물에서 지장김치의 섭취가 혈액 지질 프로파일, 혈당, ALT, AST 수준을 낮추고 인슐린 분비능력을 개선하여 줌으로써 항당뇨 및 알코올성 간 손상 보호효과를 갖는다는 사실을 보여준다.

To develop Gamma-aminobutyric acid(GABA)-producing probiotics we isolated GABA-producing lactic acid bacteria from kimchi. 17 strains of GABA-producing lactic acid bacteria were isolated among 703 lactic acid bacteria originated from 21 kind of kimchi. Two strains, K991 and K998, were selected with highest GABA production ability. The results of 16S rRNA gene sequence analysis, K991 and K998 were identified as Lactococcus lactis, which showed 99.93% and 99.87% similarity, respectively. When the two strains were cultivated in MRS containing 5% MSG at 30°C, GABA began to be produced after 12 hours, reaching maximum production at 40 hours(13.20 mM and 13.35 mM, respectively). In contrast, GABA production was about three times lower when MSG was not added.

The purpose of this study is to optimize the composition of the medium for turmeric fermentation and to select competent turmeric fermentation strains using bacterial isolates from kimchi. Initially, 30 isolates from kimchi were cultured in 5% (w/v) yeast extract and 1% (w/v) maltodextrin to determine viability. As a result, eight strains showed a tendency to maintain viability until the fifth day of fermentation. Subsequently, the eight isolates were fermented in an optimum medium for turmeric fermentation, 5% (w/v) yeast extract, 1% (w/v) maltodextrin, and 5% (w/v) turmeric for seven days to determine the viable cell count and antioxidant capacity. The antioxidant capacities of turmeric fermented by the eight isolates were similar or higher than turmeric fermented by Lactococcus lactis KCTC 2013, while maintaining high viable cell counts of both the eight isolates and L. lactis KCTC 2013 until the seventh day of fermentation. The antioxidant capacities of the selected five strains during fermentation might increase possibly due to the biological conversion of active compounds in turmeric by fermentation. Consequently, a total of five strains of the isolates showing higher antioxidant capacity (4.81±0.19-5.81±0.04 VCE/mL) than fermentation day 0 were selected for fermentation of turmeric.

In this study, an appropriate modified atmosphere packaging (MAP) condition to minimize physiological disorders while lowering weight loss was sought. To reduce weight loss during storage, kimchi cabbages packed with 0, 32, 40, 48 perforated low-density polyethylene (LDPE) films, with a diameter of 14 mm, were stored in pallet units for 90 days at 1-2oC, and their loss rate, physiological disorders, total bacteria count, pH, and solid content were analyzed. It was found that as the number of holes increased, the weight loss ratio increased proportionally. However, the difference between the perforations was relatively small compared with the sample without film packaging. On the other hand, it was also observed that the lower the number of holes was, the lower the incidence of physiological disorder was because the cold air penetrated through the perforated hole while inhibiting physiological effects, releasing heat and carbon dioxide generated by respiration. Considering the weight loss rates and physiological disorders such as black speck and soft rot, the kimchi cabbage packed with 48 perforated films (73.9 cm2) exhibited the most satisfactory condition. Using this storage condition, along with 2-3oC temperature and 91-95% relative humidity inside the pallet, a highly suitable condition for kimchi processing was obtained to secure kimchi cabbage.

Spring kimchi cabbage was stored fresh for 90 days in a commercial cold storage house. It was sanitized by spraying fungicide on the field before harvesting. The plastic boxes of spring kimchi cabbage were put on the pallet, covered with a 40-hole film, then stacked in the cold storage room at once. The room was maintained for 90 days at 0.7oC after cooling gradually at 2 oC/day. After 90 days, the weight loss was 4.73% and the total trimming loss was 8.26%. The weight loss was 8.08% and the net trimming loss was 3.26% after 90-day storage with partial stack cooling at 2.7oC covered with a 56-hole film. The quality of spring kimchi cabbage after 90-day storage was fresh without physiological disorders.

Fungicide spraying and PVC (polyvinyl chloride) wrapping were carried out for the improvement of storage yield in winter kimchi cabbage. Acetic acid, rox, tebuconazole and fludioxonil were sprayed on the cabbage, and then cabbage boxes were wrapped with 0.02 mm polyvinyl chloride film. The weight loss ratio of wrapped cabbages were 8.62% and 15.71% in unwrapped cabbages. Trimming loss ratio was the lowest in the mixed treatment of acetic acid, rox and tebuconazole in wrapped cabbage. Physiological disorders of 90-day stored cabbage was better in wrapped cabbage, especially with the mixed treatment of acetic acid, rox and tebuconazole. Wrapping and fungicide treatment reduced the storage loss ratio and physiological disorder for storage of kimchi cabbages.

This study examined the combined effects of high hydrostatic pressure (HHP) and micro-perforated (MP) film packaging on the microbiological and physicochemical qualities of kimchi sauce stored under fluctuating temperature conditions. Before storage, treatment with 600 MPa HHP reduced the total lactic acid bacteria in the sauce samples to below the detection limit (1 log CFU/g). After 68-day storage, ten microbial strains isolated from the non-treated controls were identified as Pediococcus pentosaceus, whereas eight microbial strains isolated from the HHP-treated samples were identified as Bacillus spp., regardless of the packaging type. Additionally, the samples treated with HHP and packaged in a multilayer film bag (ML-HPP), as well as those in the MP-HHP group, exhibited higher pH values and reduced sugar content than the ML-control or MP-control after 68-day storage. No significant differences were observed between the control and treatment groups regarding their electrical conductivity, salinity, and CIE a* values at the end of storage. However, there was no O2 reduction or CO2 accumulation in the MP-HHP group after 68-day storage. These results indicate that the combination of HHP treatment and MP-film packaging can extend the kimchi sauce's shelf life without packaging expansion during long-term storage.

When kimchi is frozen and thawed, the amount of lactic acid bacteria (LAB) and yeast is usually reduced by more than 2 logs, and its texture including its crispness and hardness are changed significantly. As a possible means to minimize these problems, various freezing (direct freezer with -25, -40, and -60oC and plate freezer with -40oC) and thawing methods (radio frequency (RF) thawing, plate thawing, and room temperature thawing) were investigated in terms of the amount of LAB and texture of kimchi. From the use of plate freezing and plate thawing, the amount of LAB of white cabbage kimchi could be maintained by more than 10% of its initial amount while that for red cabbage kimchi could be maintained by more than the initial amount. Pretreatment with trehalose (19 oBrix soluble solid content) to salted Chinese cabbage could maintain kimchi’s hardness and crispness. In order to maintain the texture and the amount of LAB in kimchi, the use of the plate freezer (-40oC) and the plate thawing (20oC) seemed to be effective with the assistance of trehalose.

After making kimchi by adding 0, 0.5, 1.0, 1.5% aronia (Aronia melanocarpa), microbiological and sensory characteristics were measured while fermenting it at 10oC for 28 d. The numbers of total cell and lactic acid bacteria were decreased after the maximum levels of microbial counts; that is, day 3 for control and 0.5% treatment and day 14 for 1.0, 1.5, and 2.0% treatments. Coliforms were not detected after 7 d in control and 0.5% treatments; however, they were detected after 14 d i-n 1.5 and 2.0% treatments throughout the fermentation period. Sensory properties were evaluated in the aspects of both acceptability and intensity characteristics. In the preference characteristics, overall acceptability was highest in the 1.0% group after preparation and after 14 d of fermentation. As for the aronia-added group, the intensity of the hot taste of Nabak Kimchi decreased while that of its sweet taste and sour taste increased according to the rise of both the amount of the added aronia to the kimchi and fermentation period. In conclusion, the addition of 1.0% aronia can be used to produce high-quality Nabak Kimchi while extending its storage period.

This study was conducted to investigate the quality of kimchi cabbages stored under a pallet unit-controlled atmosphere (PUCA), containing 2% O2 and 5% CO2, and to develop quality prediction models for cabbages stored under such conditions. Summer and winter cabbage samples were divided into PUCA-exposed groups and atmospheric airexposed control groups (in a cold storage). The control summer cabbages lost up to 8.31% of their weight, whereas the PUCA-exposed summer cabbages lost only 1.23% of their weight. Additionally, PUCA storage effectively delayed the reduction in cabbage moisture content compared with the control storage. After storage for 60 and 120 days of the summer and winter samples, respectively, the reducing sugar contents were higher in the PUCA groups than in the control groups. The linear regression analysis-derived equations for predicting the storage period, weight loss, and moisture content in the control groups, as well as those for predicting the storage period and weight loss in the PUCA groups, were appropriate according to the adjusted coefficient of determination, root mean square error, accuracy factor, and bias factor values. Therefore, this PUCA system would be useful for improving the shelf life of the postharvest summer and winter cabbages used in the commercial kimchi industry.

월동배추 저장 특성과 이용 시 봄배추와의 차이를 비교하였다. 월동배추의 산업현장에서 저장 특성을 조사하여, 현장에 나타나는 현상과 개선 방향을 파악하고자 하였다. 월동배추인 ‘남도장군’을 산업현장에서 저온으로 그물망 저장을 하여 16주 동안 조사한 결과, 월동배추의 외관이 변하여 상품성은 떨어졌지만, 내부 상태는 양호하여, 신선배추로 판매보다는 가공용으로 이용 가능한 것으로 나타났다. 월동배추는 저장 중에 외관 및 생체중량, SPAD지수, 색상차에서 저장 동안에 지속적으로 감소하나, 8주까지 실증 현장의 배추는 신선 배추로 판매가 가능해 보였는데, 이후 저장 종료 시까지 월동배추의 겉잎 부패로 인한 손실로 신선하게 유통하기에는 부적합해 보였다. 그러나 저장 16주간의 실증에서 월동배추 내부의 경도, 당도 등 에서는 큰 변화가 없는 것으로 나타나서, 가공 시 다듬어 손질한다면 큰 문제는 없을 것으로 판단되었다. 월동배추인 ‘남도장군’을 저장 후 봄배추인 ‘춘광’과 결구의 개체 별 특성을 비교하였는데, SSC를 제외하고는 구중과 같은 특성에서 큰 차이를 보이지 않았다. 저장했던 월동배추가 절임 시 조사를 통해 pH를 제외한 염 특성이나 EC에서 차이를 보이지 않아, 봄배추와 비슷한 가공 적성을 가지고 있는 것을 확인하였다. 본 연구에서 월동배추의 저장 특성을 농산업 현장에서 실증하였고, 봄배추와 저장한 월동배추의 품질과 가공용으로 이용 시 특성을 비교 검토하였다.