• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.122-128
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• 2005

Contamination levels of total aerobic bacteria, coliforms, Esherichia coli, Staphylococcus aureus, Bacillus cereus, and Listeria monocytogenes of Kimbab and its main ingredients sampled from general and specialized restaurants were compared. Total aerobic bacteria and coliform counts of Kimbab samples from both restaurant types were not significantly different (p>0.05), showing approximately $4\;to\;6\;log_{10}CFU/g$. E. coli counts were significantly higher in kimbab from general restaurants ($65%:\;0.7-2.6\;log_{10}CFU/g$) than those from specialized ones ($8.33%:\;0.70log_{10}CFU/g$), whereas those of S. aureus and B. cereus were not significantly different (p>0.05). L. monocytogenes was not detected in all Kimbab samples. These results indicate hygiene of Kimbab and its main ingredients are deleterious. Contamination levels of pathogens determined in the present study may be used as primary data for microbial risk assessment.

• Journal of Food Hygiene and Safety
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• v.10 no.3
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• pp.175-180
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• 1995

The distribution of bacteria in kimbab and its ingredients have been investigated. The total bacterial counts were over 3$\times$106/g(n=30) when the kimbabs were delivered to restaurant and it exceeded the legal level 1$\times$106/g defined by the Code of Food Standard in 1991. The gram-negative coliforms were also detected 1.9$\times$105. In order to study the cause of bacterial contamination in kimbabs, the ingredients used in kimbabs were examined. The bacterial counts were found 104-108/gfor kim (laver), 104-108/g for sausage, 104-106/g for boiled-spinach, 103-107/g for carrot, and 104-106/g for Danmuji, respectively. From these results it could be concluded that the bacterial contamination in Kimbabs was caused mainly by the ingredients such as kim, boiled-spinach, carrot, and sausage. Therefore, this suggested that the sanitary manufacture of kim, the storage at refrigerator temperature of the ingredients for kimbabs, and the proper treatment of equipments should be maintained in order to reduce the bacterial contamination for kimbabs. Furthermore, it should be required to obtain the basal data for establishment of the sanitary standard of kim and kimbab.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1240-1245
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• 2008

Kimbab is the most popular ready-to-eat (RTE) food in Korea. A rapid detection method based on multiplex PCR technique was developed for detection of major food-borne pathogens like Salmonella spp., Shigella spp., Bacillus cereus, Listeria monocytongenes, and Staphylococcus aureus. Specific bands were obtained as 108 bp (Sau, S. aureus), 284 bp (Sal, S. enterica, S. enteritids, and S. typhmurium), 404 bp (Lmo, L. monocytogenes), 475 bp (Bce, B. cereus), and 600 bp (Shi, S. flexineri and S. sonnei). Visible cell numbers varied from 4.14-5.03, 3.61-4.47, and 4.10-5.11 log CFU/g in randomly collected June, July, and August samples, respectively. Among the 30 kimbab samples obtained 83.3% samples were contaminated and 16.7% samples were free from contamination. The highest rate of contamination was with S. aureus (56.7%) followed by B. cereus (43.3%), Salmonella spp. (36.7%), Shigella spp. (13.3%), and L. monocytogenes (6.7%). The identification of the pathogenic species could be faster using one polymerase chain reaction (PCR) and the ability to test for food-borne pathogenic species in kimbab will save time and increase the ability to assure its quality.

• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.61-67
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• 2000

Bacteriological quality evaluations were carried out for rice rolled in laver(Kimbab), Hamburger, Walnut cake and chinese noodle (Jajangmyun), which were on sale in April and May 1995, in May and July 1997 and in January 1999, at 20 different resting places on Kyung-Bu, Ho-Nam, Joong-Bu and Young-Dong Highway in Korea. Food poisoning bacteria were not detected. However numerous coliform bacteria were dectected saying that the sanitary condition of foods on sale at resting places of the highways was not hygienic. There exited 8.8$\times$10$^{4}$~6.6$\times$10$^{5}$ cells/g of coliform bacteria in all the Kimbab sold in 1995. As for Hamburger, 1.8$\times$10$^{2}$~4.7$\times$10$^{4}$ cells/g of coliform bacteria proliferated in all the samples. In 1997,E. coli was found in 16 cases and 21 cases respectively out of 22 Kimbab samples, Hamburger dealing at 7 resting places out of 14 were contaminated with 1.7$\times$10$^{2}$~1.9$\times$10$^{7}$ cells/g of coliform bacteria and Hamburgers dealing at 2 resting places were infected by 5. coli. In contrast to the Kimbab and Hamburger, all the 6 Walnut cake samples were free from the microbial pollution exhibitory that their hygienic condition was satisfactory. 3 samples out of 6 Jajangmyun were contaminated by 7.1$\times$10$^{2}$~2.0$\times$10$^{3}$ cells/g of coliform bacteria, but E. coli was not detected. Compared Kimbab sold in 1995 and 1997 with 1999, Kimbab sold in it can be said that hygienic control fur Kimbab should be performed more strictly during hot season than during cold season. Walnut cake was the safest against microbial contamination, followed by Jajangmyun, Hamburger and Kimbab in decreasing order, indicating that foods with mixed ingredients such as Kimbab and Hamburger were more susceptible to microbial infection, so that a more systematic safety control is needed for such foods during cooking, processing and distribution.

• Applied Biological Chemistry
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• v.51 no.4
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• pp.329-333
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• 2008

This study was designed to estimate the shelf-life of the popular chilled foods kimbab (rice rolled in dried laver), samgak kimbab (triangular rice rolled in dried laver), eomook (fish surimi, boiled fish paste) mook (acorn-starch jelly), and tofu (soybean curd) in large discount markets and convenience stores. Different types of chilled foods were stored at 5, 7, and 10 for 7 and 28 days, and changes in the total numbers of the aerobic bacteria were monitored. Values of 6 and 7 log cfu/g were used as the standard. Ready-to-eat foods stored at 5 showed a much longer shelf-life compared to storage at 10. The respective percentage increases in the shelf-life observed at both 7 and 5 were kimbab (70%, 171%), samgak kimbab (87%, 143%), soybean curd (46%, 95%), fish surimi (46%, 99%), and mook (45%, 87%). To reduce the microbiological contamination, storages at 7 and 5 are recommended for the increases of 45-88 and 87-171% in the shelf-life of these chilled foods.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.323-331
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• 2007

This study was designed to estimate self-life of Kimbab and sandwiches marketed in convenience store. While the 12 different type of Kimbab (n=6) and sandwiches (n=6) were kept at $10^{\circ}C$ for 72 hours, quality changes including volatile basic nitrogen, aerobic plate count, pathogens detection and sensorial property was monitored, and effective quality indicators were selected. Volatile basic nitrogen, indicator for protein deterioration was slightly increased during storage periods in all samples. E. coli, Staphylococcus aureus, Salmonella spp. and Vibrio parahaemolyticus were not detected from any of samples. Change of aerobic plate count of Kimbab and sandwiches were increased moderately but increased dramatically after 48 hours of storage. Overall acceptability were maintained over 5, purchasing power limit, for 40 hours in 4 general Kimbab, 48 hours in 2 samgak Kimbab and 42 hours in 2 sandwiches. Shelf-life of each item was calculated from regression equation between reference limit from effective quality indicators, aerobic plate count and sensory property, and storage period. Estimated shelf-lives of general Kimbab were $15{\sim}33$ hours, samgak Kimbab were 32 hours and sandwiches were $27{\sim}30$ hours at $10^{\circ}C$ refrigerated condition.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.279-286
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• 2005

Microbial contamination origin of Kimbab was determined using nine types of ready-to-use ingredients, three each from animal, seafood, and vegetable sources. Effect of radiation on microbiological safety was also investigated. Total aerobic bacteria were not detected in seasoned beef, ham, and seasoned burdock, whereas 3.50, 5.41, 8.83, and 5.07 log CFU/g were detected in surimi gel, seasoned and blanched spinach, dried laver, and cucumber, respectively. Total aerobic bacterial and mold numbers were 8.73 and 5.08 log CFU/g in prepared Kimbab. Gamma irradiation reduced level of contaminated aerobic bacteria and mold population in Kimbab and its ingredients, Salmonella mutagenicity assay (Ames test) showed Kimbub ingredients irradiated at 10 kGy did not show any mutagenicity. These results indicate ready-to-use kimbab ingredients were mostly responsible for total aerobic bacteria and mold population of Kimbab, and low dose irradiation and low temperature storage ($10^{\circ}C$) effectively ensured microbiological safety of Kimbab and ready-to-use ingredients.

• Journal of Food Hygiene and Safety
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• v.21 no.3
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• pp.189-195
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• 2006

This research was designed to evaluate the nutritional an microbiol quality assessment of Chungmukimbab purchased from market in Tongyeoung area. Contents of calories, calcium, iron, thiamin and riboflavin in ordinary kimbab and Chungmukimbab were lower than the recommended levels of Korean adult men. So, We suggested that a fruit, beverage and ffod stuff were supplemented to maintain nutritional balance. Total aerobic bacteria and coliform group of just prepared ordinary kimbab and Chungmukimbab samples from market were not significantly different, showing approximately $5.50{\pm}0.38 log_{10} CFU/g,\;2.10{\pm}0.47log_{10}MPN/100g$ in ordinary kimbab, $5.61{\pm}0.42log_{10}CFU/g,\;1.75{\pm}0.34 log_{10} MPN/100g$ in Chungmukimbab, respectively. Total aerobic bacteria of law ingredients of chungmukimbab sample were 3 to $4 log_{10}CFU/g$ in kimbab, seasoning squid and radish roots kimchi, 4 to $5 log_{10}CFU/g$ in boiled fish paste. The coliform groups were 1 to $2 log_{10}$ MPN/100 g in kimbab, seasoning squid and radish roots kimchi, 2 to $3 log_{10}$ MPN/100g in boiled fish paste. Detection rate of E. coli and Staphylococcus aureus counts were 10.0, 12.5% in Chungmu-kimbab, 15.0, 10.0% in seasoning squid, 0, 10.0% in radish roots kimchi respectively, not detected in boiled fish paste samples. During storage at $15^{\circ}C$ for 24 hours, total aerobic counts and coliform groups in ordinary kimbab and Chungmukimbab were increased by the 1.94, $0.97log_{10}CFU/g$, 0.60, 0.72 log10 MPN/100g respectively. Total aerobic counts of Chungmukimbab ingredients increased $0.83{\sim}l.33 log_{10}CFU/g$ at different time

• Food Science of Animal Resources
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• v.31 no.1
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• pp.40-46
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• 2011

The growth profile of Bacillus cereus in ready-to-eat (RTE) food products of animal origin was examined under different temperature and incubation conditions. In sandwiches and Kimbab, B. cereus did not grow or exhibited only minimal growth at 4 and $10^{\circ}C$, but it grew rapidly at ambient temperature. In sandwiches, B. cereus did not grow efficiently at $25^{\circ}C$, however, in ham, the main ingredient of sandwiches, B. cereus growth was observed at the same temperature, with bacterial levels reaching 7.94 Log CFU/g after incubation for 24 h at $25^{\circ}C$. Toxigenicity of B. cereus was observed only at temperatures above $25^{\circ}C$. In Kimbab, B. cereus produced toxin after 9 h at $30^{\circ}C$ and after 12 h at $25^{\circ}C$. Ingredients of sandwiches and Kimbab were collected from 3 different Korean food-processing companies to investigate the source of contamination by B. cereus. Among the 13 tested food items, 6 items including ham were found to be contaminated with B. cereus. Of these ingredients, B. cereus isolates from 3 items produced enterotoxins. None of these isolates harbored the emetic toxin-producing gene. The findings of the present study can be used for risk assessments of food products, including ham and cheese, contaminated with B. cereus.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.4
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• pp.481-487
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• 2014

This study examined microbiological contamination of street foods(kimbab, fish cake, Korean sausage) by microbiological analysis. A collection of 360 samples of street foods was obtained seasonally in four major cities(Seoul, Daejeon, Busan, Gwangju) in Korea. Aerobic mesophilic counts ranged between 1.0 and 9.9 log CFU/g, with the highest count recorded from Kimbab. Counts of psychrotrophic microorganisms were as high as those of mesophilic microorganisms. Total coliform populations between <1.0 and 7.5 log CFU/g were found in 53.6% of samples. Escherichia coli 4.4%, Staphylococcus aureus 7.8% and Clostridium perfringens 3.3%. Salmonella spp. and Listeria monocytogenes were not detected in any of the samples. Kimbab purchased in spring and summer showed higher S. aureus and Cl. perfringens contamination rates. Microbial contamination levels determined in the present study may be used as the primary data to execute microbial risk assessment of street foods.