• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.468-476
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• 2020

We aimed to analyze the microbiological quality of the ready-to-eat (RTE) side dishes collected from traditional markets, supermarkets, and cafeterias in Gyeonggi-do in 2019. A total of 108 samples were analyzed for total aerobic bacterial counts, coliforms and foodborne pathogens depending on place of purchase and cooking methods. Results show that Bacillus cereus was detected in 14 (12.9%) out of 108 samples of side dishes, while no other foodborne pathogens were detected. The mean detected level (range) of total aerobic bacteria depending on place of purchase was 5.8 log CFU/g (3.0 to 8.2 log CFU/g) for traditional markets, 4.3 log CFU/g (2.4 to 7.8 log CFU/g) for supermarkets, and 3.80 log CFU/g (0.0 to 6.8 log CFU/g) for cafeterias, indicating that there was a significant (P<0.05) difference in total aerobic bacterial counts among places of purchase. Among the samples, the highest counts of total aerobic bacteria and coliforms were detected in saengchae (raw vegetables), followed by namul (seasoned herbs, vegetables), bokkeum (stir-fried foods), and jorim (foods cooked in soy sauce). The growth of total aerobic bacteria in seasoned soybean sprouts was inhibited when the sprouts were stored at 4℃ up to 24 h, whereas bacteria rapidly grew at 20 and 35℃ after 3 and 6 h, respectively. These results reveal that storage temperature might play a significant role for the microbiological quality of seasoned soybean sprouts when they are sold in markets. Thus, this study suggests that RTE side dishes should be stored at refrigerated temperature when being sold at markets as well as after purchasing to improve their microbiological quality.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.626-634
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• 2007

This study investigated the effects of 3% ground fresh paprika (FP) and 5% freeze-dried paprika powder (FDP) on lipid oxidation inhibition and warmed-over flavor (WOF) development in cooked ground pork (CGP; meat:fat = 70:30), using two packaging methods (atmosphere packaging and vacuum packaging) during 8 days at $4^{\circ}C$ and 4 months at $-26^{\circ}C$. In the CGP containing FP with atmosphere packaging, at both $4^{\circ}C\;and\;-26^{\circ}C$, peroxide formation increased sharply, and was similar to that of the CGP without paprika. Peroxide formation, in both the CGP without paprika and with FP and packaged with vacuum packaging, repectively, was much lower than that found with atmosphere packaging. Vacuum packaging was superior to atmosphere packaging for lipid oxidation inhibition. In the CGP containing FP with vacuum packaging and stored at $-26^{\circ}C$, peroxide formation almost didn't occur, which was similar to the CGP containing FDP. The peroxide value and thiobarbituric acid (TBA) value did not increase in the CGP containing FDP over the storage periods ($4^{\circ}C\;and\;-26^{\circ}C$) for both the atmosphere and vacuum packaging. Therefore, FDP was the most effective for lipid oxidation inhibition during refrigerated storage, regardless of the packaging method. Both FP and FDP with vacuum packaging during frozen storage showed similar antioxidant activities. The development of WOF in the CGP containing FDP with vacuum packaging was delayed until 7 days at $4^{\circ}C$ and 3 months at $-26^{\circ}C$, respectively. WOF was highly correlated with TBA value in the CGP stored at $-26^{\circ}C$ with vacuum packaging (r = 0.88, p<0.05). The oxidative stability of the lipid in the CGP containing FDP with vacuum packaging was excellent.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.269-276
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• 2010

The objective of this study was to determine the effects of residual nitrite contents, chitosan with different molecular weight and nitrite addition on emulsified sausage during cold storage. Six types of sausages were evaluated: control, 0.5% 50 kDa chitosan (T1), 0.5% 200 kDa chitosan (T2), 150 ppm nitrite (T3), 0.5% 50 kDa chitosan+150 ppm nitrite (T4), and 0.5% 200 kDa chitosan+150 ppm nitrite (T5). Each type of sausage was tested in triplicate and assigned to one of four storage periods: 0, 10, 20 and 30 days. As the storage time increased, the presence of chitosan and nitrite resulted in decreased residual nitrite value and increased pH (in control and T2), TBARS (thiobarbituric acid reactive substance) values, and total plate counts (TPC). Values for pH, TBARS, residual nitrite and total plate counts decreased significantly in response to the addition of chitosan and nitrite relative to the control (p<0.05). T5 was redder than the control (higher CIE$a^*$) at 30 d; however, no difference in the CIE $L^*$ and $b^*$ values was observed. T5 was significantly (p<0.05) more effective at delaying lipid oxidation when compared to the other treatment groups. T5 presented TPC that was significantly lower (p<0.05) than the other groups after three days of storage. In addition, the use of chitosan and nitrite in combination had much better antioxidant and antimicrobial effectiveness than other treatment groups. In conclusion, this study demonstrates that the addition of 0.5% 200 kDa chitosan and 150 ppm nitrite in combination with emulsified sausages tended to improve antioxidative and antimicrobial effects during storage when compared to other treatment groups.

• Food Science and Preservation
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• v.30 no.1
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• pp.88-97
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• 2023

As livestock consumption in Korea has been gradually increasing, the quality of the final products has been improved to meet this increased demand. In particular, maintaining the water holding capacity (WHC) and minimizing the drip loss during the thawing of frozen meat are of utmost importance. This study investigated the physicochemical properties of frozen pork subjected to thawing under different conditions: at room temperature (20℃, under air), at a low temperature (4℃ refrigerator, under air), under water (20℃, under water in a vacuum bag), under microwave (microwave-thawing, 260 W), and under low-pressure tumbling (20℃, 0.015 bar, tumbling). The shortest thawing time for frozen pork was recorded upon low-pressure tumbling thus indicating a fast heat transfer. The lowest drip loss (0.2%) and highest WHC (94.5%) were also recorded under this condition. A significantly higher drip loss was observed upon microwave- (1.0%) and water-thawing (1.2%), which resulted in the lowest WHC in microwave thawing (87.2%). The highest total count of aerobic bacteria and coliform group were observed upon room temp thawing while the low pressure tumbling and thawing resulted in the lowest aerobic bacteria (1.90 log CFU/g) and coliform (0.78 log CFU/g) count. Consequently, thawing by low pressure tumbling afforded the best food quality.

• Korean Journal of Food Science and Technology
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• v.19 no.3
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• pp.250-256
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• 1987

An attempt was made to establish a simple and rapid method for the evaluation of Kimchi quality. Four kinds of Kimchi included one home made traditional Kimchi were stored at $4^{\circ}C$ and$25^{\circ}C$ and biochemical changes, including pH, total acidity, volatile acidity, volatile basic nitrogen, vitamin C, NaCl, glucose, nitrite and resazurin value were determined and tested for the relationship with sensory evaluation. The change in pH, total acidity and resazurin value were highly correlated with the sensory maturity of Kimchi-Resazurin value was strongly influenced by the sample dilution and fermentation temperatures. It was concluded that resazurin test with sample solution of $2{\sim}4%$ could be used as a rapid method for the estimation of the maturity of Kimchi.

• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.421-426
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• 1986

The carbohydrate characteristics and storability of two Korean traditional confections Seban-kangjeong (a Korean fried waxy-rice cookie) and starch-dashik (a Korean pressed starch cookie) were studied as compared with two Western confections fried cookie and biscuit. Seban-kangjeong showed lower contents of starch and sucrose and higher content of reducing sugar whereas starch-dashik showed higher contents of starch and sucrose and lower content of reducing sugar. Moisture content was higher in Korean confections than in Western confections. The degree of gelatinization was higher in Seban-kangjeong and fried cookie which were made through a frying process. Moisture adsorption isotherms were constructed for the four products. In storage test for 6 months under different temperature and humidity conditions, the relative humidity maintaining the initial moisture content of products was 68% for Seban-kangjeong and starch-dashik and 20% for fried cookie and biscuit. The ratio of retrogradation in storage was 15% in Seban-kangjeong, 20% in starchdashik and 28% in fried cookie and biscuit, showing the lowest progress in freezer storage.

• Food Industry
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• s.220
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• pp.22-65
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• 2011

${\bigcirc}$ 본 업소는 냉동식품(냉동만두류, 냉동면류, 냉동피자)를 생산하는 식품제조 가공업소로서 총 5명의 인원이 냉동식품 3개 제품을 생산하여 매출액은 (약00원)이며 주로 대형 유통 판매업소에 판매하고 있다. ${\bigcirc}$ 본 업소의 냉동식품은 축산물(돈육) 농산물 등과 밀가루, 소금 등을 배합 성형 후 가열 등의 공정을 거쳐 생산된 제품으로 원료 취급과정에서의 오염이나 불충분한 가열, 교착오염 등으로 식중독균(병원성대장균, 황색포도상구균등)과 원료 및 제조과정에서 이물(금속등)이 혼입할 수 있으며, ${\bigcirc}$ 이로 인한 주요클레임 발생사례는 최근 3년간 관계당국으로부터 대장균군 검출 3건, 소비자클레임 2건이 있었다. - 연도별 주요 클레임내용은 '08년도에는 대장균군 검출 3건(냉동만두류), '09년도 날벌레 이물검출 1건(냉동피자), '10년도에는 철수세미1건(냉동면류)이었다. ${\bigcirc}$ 이러한 위해발생을 사전에 예방하기 위해 중점관리해야하는 공정은 가열(중숙, 탕숙, 가열 굽기)공정, 세척공정으로 판단되며, 금속 등의 이물 혼입 또한 중점적으로 관리할 필요성이 있다. ${\bigcirc}$ 본 업소에서 생산하는 냉동식품(냉동만두류, 냉동면류, 냉동피자)는 가열(중숙/탕숙/가열/굽기)공정 및 세척공정에서의 가열(중숙/탕숙/가열/굽기) 후 품온을 설정하여 CCP 1로, 세척시간과 세척수량, 원물량을 설정하여 CCP 2로 관리하고 있으며, 2시간마다 모니터링하고 한계기준 이탈여부를 기록하도록 하고 있다. ${\bigcirc}$ 종합적인 공정 및 일반위생관리를 위해 개인위생 상태, 냉동 냉장고 온도 확인 등 총 30개 항목에 대하여 정기적 점검(매일 18, 주간 4, 월간 4, 분기 1, 연간 3)을 실시하고 있으며, ${\bigcirc}$ 따라서 지속적인 모니터링을 통해 미흡사항의 원인으로 파악하고 문제점 제거를 위해 체계적이고 지속적인 관리가 필요한다.

• Journal of Environmental Health Sciences
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• v.28 no.2
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• pp.161-171
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• 2002

The number of food establishments selling raw and convenience foods are increasing in Korea, and people enjoy purchasing and eating foods at these shops. However, there are only a few reports on the temperature control of the refrigerators and freezers at retail food shops. This study was performed to investigate the temperature control of refrigerators and freezers in retail food shops in Daegu. The survey was carried out from July 20 to August 30 in 2001. The trained surveyors visited the twenty retail food shops (four department stores, eight marts/supermarkets and eight convenience stores) in the 8 major areas of Daegu and inspected the temperature control of 48 refrigerators for dairy products, fruits & vegetables, and rolled rice & sandwiches, and 52 freezers for ice cream & sherbet, frozen food, and frozen fish. The percentage of the refrigerators, and freezers with unsafe temperatures higher than the recommended safe temperature (10℃ for refrigerators, and -18℃ for freezers) was 42%; 45.8% in refrigerators; 38.5% in freezers. On an average, the bigger the size of the shop, the better than the other freezers. On the other hand, the temperature control of refrigerator for fruits & vegetables was the worst because they were usually open. Actual temperatures in the refrigerators and freezers were found to be significantly higher than the reading on the thermometers attached to the refrigerators and freezers(p<0.05). These results indicate that temperature control of refrigerators and freezers at retail food shops should be monitored several times each day, and should have strict inspection. There should be more detailed legal standard and specification for temperature control of refrigerators and freezers at retail food shops to prevent foodborne illness from unsafely stored food.

• 한국해양학회지
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• v.25 no.4
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• pp.240-244
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• 1990

To solve two problems, temperature shock to the man and difficulty in exchanging the air in the glove box into N2 gas, during the subsampling of Suboxic and cold core sediments, a portable glove box with a refrigerating machine and a gas exchanging bag was constructed for subsampling of sediment cores on board. The refrigerator of the glove box can cool down 200 litter air at 30$^{\circ}C$ to 2$^{\circ}C$${\pm}$2$^{\circ}C$ within 5 minutes. The box was successfully operated during the second KORDI's deep sea research cruise of 1989 in the North equatorial Pacific. Pore water data obtained from the cruise show no evidence for artifacts caused by warming up or oxidation of sediments during subsampling.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.447-453
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• 1985

The effects of preheating and calcium chloride on prevention of tissue softening was examined during fermentation and storage of radish root kimchi. In order to find the optimum condition of preheating treatment, activities of pectinesterase (PE) and polygalacturonase (PG) in radish root were measured with respect to $CaCl_2$ concentration and temperature. A maximum firmness was obtained with treatment in 0.05M $CaCl_2$ at $55^{\circ}C$ for 2hr which was optimum conditions for PE activity, while PG was inhibited at the $CaCl_2$ concentration of 0.05M. Firmness of radish root kimchi prepared by preheating treatment was decreased little during fermentation and storage for 25 days.