• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.22 no.2
• /
• pp.70-78
• /
• 1989

This experiment was carried out to develop the preparation method of chitosan which has strong antimicrobial activity, and also tried to investigate as a natural food preservative with this chitosan. The antimicrobial activity of chitosan was the strongest when deacetylation of chitin was conducted at $146^{\circ}C$ for 8 hours with $50\%$ sodium hydroxide. The growth of Escherichia coil was completely inhibited by adding this low molecular weight chitosan (M. W, 35,000) at the level of concentration of 75ppm to the medium. The antimicrobial activity was strong enough against such Gram positive bacteria as Staphylococcus sp. and Bacillus sp.. The growth of these strains was inhibited by the concentration of 50ppm but it was varied in its kinds against Gram negative bacteria. The concentration of chitosan re-quired for growth inhibition of microorganisms was 100ppm against Pseudomonas sp. and Vibrio sp., 2,000ppm against Salmonella sp.. The growth of Saccharomyces sp. was inhibited by the concentration of 100ppm, but Hansenula sp., Aspergillus sp., Penicillium sp. and Mu-cor sp. did not inhibited by even more than the concentration of 5,000ppm. The shelf life of Mulkimchi (pickle type Kimchi), containing $0.2\%$ chitosan was 10 days longer than control stored at $5^{\circ}C$.

• Food Science of Animal Resources
• /
• v.32 no.5
• /
• pp.669-677
• /
• 2012

The objective of this study was to analyze the flavor pattern of different varieties of cheeses. Four of the each following cheese varieties such as shred type pizza cheese, Cheddar cheese, Mozzarella block cheese, and white mold-ripened cheeses, stored at $4^{\circ}C$ during 2 wks were examined before and after cooking at $70^{\circ}C$ and $160^{\circ}C$. Flavor patterns of these cheeses were analyzed using an electronic nose system based on mass spectrometer. All data were treated by multivariate data processing based on discriminant function analysis (DFA). The results showed the discriminant model by DFA method. Data revealed that flavor patterns of pizza cheeses were well separated as storage prolonged and obviously discriminated as the higher the cooking temperature. The result of pattern recognition analysis based on discriminant function analysis showed that new brand of pizza cheese produced by Imsil Cheese Cooperative was located at middle between the flavors of the imported brands of pizza cheese and those of domestic brand of pizza cheeses. Imsil cheese has a unique flavor pattern among other variety of cheeses. Application of pattern recognition analysis by electronic nose might be useful and advanced technology for characterizing in flavor pattern of cheese products from different origins and different categories of cheeses.

• Korean Journal of Food Science and Technology
• /
• v.21 no.1
• /
• pp.109-119
• /
• 1989

To improve the storage method of Kimchi, optimum ripening Kimchi for an irradiation treatment(the time of around 0.3% in total acidity of Kimchi) was irradiated by doses of 1, 2, 3 kGy with Co-60 ${\gamma}-radiation$ and stored at $10^{\circ}C$. Total aerobic bacteria increased in the beginning of storage and then decrease slowly as the number of total lactic acid bacteria increased. Total lactic acid bacteria initially loaded by $10^8\;cells/ml$ in Kimchi shortly after irradiation reduced to $10^4-10^6\;cells/ml$ with 1-3 kGy doses and decreased gradually through the whole storage period. The initial load of yeast, $10^3\;cells/ml$, increased steadily during Kimchi storage and led to more than $10^4\;cells/ml$ after 30 days of storage. While it maintained tha the load in 2-3 kGy irradiated groups after 30 days of storage was less than that at the beginning of storage. pH, acidity and volatile acid in the nonirradiated group were 4.0, 0.7% and 0.06%, respectively at the 15th day after storage, but at the 30th day after storage, 2-3 kGy irradiated groups showed different values, 4.1, 0.58-0.63%, and 0.04-0.05%, respectively. The texture(firmness) of Kimchi reduced along with storage time, and 2 kGy irradiated group proved most favourable in its texture during storage. In the sensory evaluation of Kimchi, nonirradiated group was inedible after 15 days of storage, whereas 2-3 kGy irradiated groups could proling the storage-life of Kimchi over 2 times compared with the nonirradiated Kimchi, showing the good sensory quality even after 30 days of storage.

• Journal of KIISE:Software and Applications
• /
• v.28 no.1
• /
• pp.52-63
• /
• 2001

필기 단어 인식 방법에는 낱자별 분할 및 낱자 단위 인식을 통해 인식하는 방법과 단어 사전을 이용하여 단어와 영상을 직접 비교하는 방법이 있다. 이 중 후자는 인식 대상이 되는 단어들이 작은 수의 어휘로 제한되었을 대 매우 효과적이다. 본 논문에서는 입력 영상이 주어졌을 때 자모를 순차적으로 탐색하고 그 결과의 최적 조합을 찾아 인식하는 사전을 이용한 필기 한글 단어 인식 방법을 제안한다. 입력 영상은 사전의 각 단어와의 매칭을 통해 인식된다. 단어는 필기 순서로 정렬된 자모열로 표현하고 입력 영상은 획들의 집합으로 표현한다. 단어의 자모들은 입력 영상으로부터 추출된 획들의 집합으로부터 단계적으로 탐색된다. 각 단계에서는 전 단계까지의 매칭 상태와 탐색하려는 자모의 형태로부터 자모가 존재할 것이라고 기대되는 정합 기대 영역을 설정한 후 그 안에서 자모 탐색기를 이용해 자모를 찾는다. 자모 탐색기는 획들의 집합으로 이루어진 복수의 자모 후보와 그 점수를 출력한다. 각 단계마다 생성된 자모 후보들은 최적의 단어 매칭을 찾기 위한 탐색 공간을 이룬다. 본 연구에서는 단어 사전을 trie로 구성하고, 탐색 과정에서 dynamic programming을 이용하여 효과적으로 탐색을 수행하였다. 또한 인식 속도를 향상시키기 위해 산전 축소, 탐색 공간 축소 등 다양한 지식을 이용하였다. 제안하는 방법은 무제약으로 쓰여진 필기 단어도 인식 할 수 있을 뿐 아니라, 동적 사전을 이용하기 때문에 사전의 내용이 변하는 환경에서도 적용할 수 있다. 인식 실험에서는 39개의 단어로 이루어진 사전에 대하여 613개의 단어 영상에 대해 실험한 결과 98.54%의 높은 인식률을 보임으로써 제안하는 방법이 매우 효과적임을 확인하였다. 아니라 곰팡이 균주도 실제 praxis에 적합하게 개발시킬수 있다. 따라서 앞으로 발효육제품제조에 있어 starter culture가 갖는 의미는 매우 중요하며 특히 짧은 숙성기간을 거치는 발효소시지의 제조에 있어서는 필수불가결한 공정의 한 분야로 자리잡게 될 것이다.큰 차이 없었으나 이중포장과 진공포장은 상당히 효과적임을 알 수 있었다.로는 18%에 비하여 22%가 더 적합한 것으로 생각되었다.$0.15{\sim}0.35%$이었다.irc}C$에서 $13.49{\times}10^{-3}$이었다. 이 값들을 Arrhenius식에 대입하여 구한 활성화 에너지는 24.795 kJ/Kmol이었다. 이 값으로부터 결정한 살균 포장약주 명가의 상용 저장 수명은 $10^{\circ}C$에서 2년, $20^{\circ}C$에서 1년 4개월, $25^{\circ}C$에서 1년 2개월 이었다. 서울의 매월 평균 온도를 기준으로 계산할 때 본제품의 상용저장기간은 1년 8개월이었다.로 반죽이 호화되고 가열시간이 그 이상으로 증가할 때도 반죽의 호화가 약간은 진행되지만 $90^{\circ}C$ 이상의 가열온도에서는 가열시간 0.5분 이내에 반죽의 호화가 급속히 일어나고 가열 시간을 증가시켜도 더이상의 호화는 일어나지 않았다. 같은 조건에서는 waxy corn starch 반죽의 호화 속도가 corn starch보다 더 빠른 것으로 나타났다. 대표적으로 52% 수분함량에서 반응속도상수(k)와 가열온도(T)사이의 관계식은 corn starch의 경우 $logk=11.1140-4.1226{\times}10^3(1/T)

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

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.11
• /
• pp.1587-1594
• /
• 2009

This study investigated the physico-chemical and sensory quality of Doenjang added with red pepper (Capsicum annuum L.) seed. The initial moisture content and salt content of Doenjang were 52.03-53.79% and 13.28-14.05%, respectively. The moisture and salt contents of Doenjang slightly decreased and increased, respectively, as fermentation periods increased. According to increasing fermentation periods, pH of Doenjang showed a little decreasing value although there were no difference between samples with various red pepper seed contents. On the other hand, titratable acidity of Doenjang increased as fermentation periods increased. Also, Doenjang added with red pepper seed had higher titratable acidity value than control Doenjang without red pepper seed. In the color of Doenjang, ‘L’ of lightness, ‘b’ of yellowness, and ‘a’ of redness were decreased as fermentation periods increased. Also, generally, increase of red pepper seed concentration resulted in higher values of redness (a), yellowness (b) and lightness (L) of Doenjang. Also, amino-type nitrogen content, which was 497-623 mg% in initial fermentation period samples, increased to 1,000 mg% for control and to 756~896 for red pepper added at the fermentation 120 days. In the total microbes, total cell count in the Doenjang samples was in the range of $10^7{\sim}10^8$ CFU/g regardless of fermentation periods. In contrast, yeast and mold number of Doenjang samples showed the range of $10^5$ CFU/g at the initial fermentation periods and decreased thereafter. In the sensory evaluation of Doenjang, unique Doenjang flavor increased regardless added red pepper seed as fermentation periods increased.

• Journal of Food Hygiene and Safety
• /
• v.25 no.4
• /
• pp.360-366
• /
• 2010

Doenjang (fermented soybean paste) is one of the korean traditional fermented soybean product which is consumed with cooked rice as a soup or paste. During the fermentation, soybean protein hydrolyzed into amino acids and various peptide, and various organic acids by mirobes related and enzymes produced by meju fermentation. Some commercial products locationally samples give more sour taste than normal due to abnormal fermentation which the reasons are not clear. Three samples that gave sour taste organoleptically were collected and analyzed their characteristics such as pH, moisture content, acidity and microbial counts. The pH of the sour sample were lower than the normal with higher acidity as pH 5.39 (normal) to pH 4.36 (S2) and 15.80 ml of(0.lN NaOH consumed) to 21.80 ml (S1) respectively. Salt and moisture contents were different with sour and normal Doenjang as 16.38% (normal) to 8.92% (S3) in salt and 55.94% (normal) to 49.34% (S1) in moisture content. Total viable counts were $4.1{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2), and $3.4{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2) in acid producing microbes at BCP plate. Yeast and mold were not detected. The composition of acids as mainly lactic acid and acetic acid of sour Doenjang. Total free amino acids content were lower the sour Doenjang than the normal.

• Journal of radiological science and technology
• /
• v.11 no.1
• /
• pp.71-77
• /
• 1988

To improve the storage method for kimchi, optimal ripening kimchi was irradiated with doses of 1, 3, 5kGy Co-60gamma radiation, followed by the microbiological, physicochemical and senosory 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 in 3 kGy irradiated group. Irradiation treatment at 3 kGy sterilized coliforms 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, increased 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 ascorbic 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 the shelf-life of kimchi more than two months as compared to control.

• Korean Journal of Microbiology
• /
• v.53 no.1
• /
• pp.39-48
• /
• 2017

In order to evaluate the diversity of microbial population of Korean traditional Deonjang and Gochujang produced in Jeju, Jeonnam, and Jeonbuk province area, microbial communities were analyzed using next generation sequencing. In this result, the dominant bacteria of Deonjang in three area were Bacillus amyloliquefaciens, Tetragenococcus halophilus, and Bacillus was major dominant bacteria in Jeonnam (43.16%) and Jeonbuk (64.54%) area. But in Jeju area, Bacillus was 0.22%, which was significantly different from the other two. Equally, the dominant fungi of Deonjang in 3 area were Candida versatilis. Common fungus in Jeonnam and Jeonbuk area was Candida sp., respectively, 64.22% and 33.68% and Micor sp. was a common fungus in Jeonnam (15.66%) and Jeonbuk area (36.73%). But in Jeju area, Candida sp. and Zygosaccharomyces rouxii were dominant than mold. Bacillus subtilis, Bacillus licheniformis, and B. amyloliquenfaciens were the preminant bacteria in the traditional Gochujang in three regions. But there were no common dominant fungi in the 3 regions. Aspergillus sp. and Rhizopus sp. prevailed in Jeju and Jeonnam region, and Zygosaccharomycess rouxii predominanted in Jeonbuk area. These results suggested that the difference in the samples collected for the study were classified into similar groups according to the characteristics of each sample rather than regional characteristics.

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