• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.696-700
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• 2009

The adaptability of dry rehydratable film for the qualitative evaluation of coliform bacteria and Escherichia coli was tested. In general, culture methods that employ lactose broth or desoxycholate lactose agar are used for qualitative tests of coliform bacteria. Culture using lactose broth showed a high detection yield and low selectivity when compared to the dry rehydratable film. However, culture methods that employ lactose broth required a long time(48 hrs) for qualitative tests of coliform bacteria and complicated procedures were required to prepare the medium. The detection of coliforms using desoxycholate lactose agar had a slightly higher selectivity than the dry rehydratable film method, but this difference was not statistically significant. However, the preparation of the desoxycholate lactose agar was complicated. EC broth for the detection of E. coli showed the highest detection yield and lowest selectivity; however, this method required complicated procedures for preparation of the medium as well. Overall, the dry rehydratable film had a slightly lower detection yield than the other methods. The detection yield of dry rehydratable film method was over 37.1% at a concentration of 1 cfu/$m{\ell}$. Additionally, the dry rehydratable film method showed high selectivity and did not require preparation. However, because the selectivity of the dry rehydratable film was high, it took a long time(36 hrs) to detect E. coli. Overall, these findings indicate that dry rehydratable film can be used for qualitative detection of coliforms and E. coli.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.8
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• pp.1128-1135
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• 2011

This study was conducted to investigate the effect of dietary green tea extract (GTE) on the performance, carcass and gastrointestinal tract (gut) traits, caecal coliform bacteria count, and pH and color (CIE $L^*$, $a^*$, and $b^*$) values of the breast muscle in broilers. A total number of 600 day-old broilers (Ross 308) was allocated to three treatments with four replicates containing 50 (25 males and 25 females) birds. The dietary treatments consisted of the basal diet as the control (0GTE) and diets with GTE at 0.1 (0.1GTE) or 0.2 (0.2GTE) g/kg. Body weights and the feed intake of broilers were measured at 1, 21 and 42 days, the feed intake was measured for different periods and the feed conversion ratio was calculated accordingly. At 42 day four birds per replicate were slaughtered for the determination of carcass and organ weights, caecal coliform bacteria count, and also quality of the breast muscle. The dietary GTE increased the body weight, feed efficiency, carcass weight and dressing percentage and decreased caecal coliform bacteria count of broilers (p<0.05). The 0GTE broilers consumed (p<0.01) less feed than the 0.1GTE birds in the entire experimental period. The relative abdominal fat weight and gut length of broilers in the 0.2GTE were tended to be lower (p<0.07) than those in the 0GTE group. The breast meat from 0.1GTE birds had a lower pH value when compared to that from 0GTE birds. The 0.1GTE broilers had lighter breast meat than 0GTE and 0.2GTE birds. The dietary GTE increased $a^*$ and $b^*$ values of the breast meat. Thus this product appeared to have a measurable impact on CIE color values of the breast meat in broilers. The results of the present study may indicate that the improved production results in the group with added GTE are directly connected with physiological mechanisms such as the regulation of the caecal micro-flora.

• The Korean Journal of Food & Health Convergence
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• v.5 no.3
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• pp.35-40
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• 2019

In this study, general bacterial counts and coliform counts, which are hygienic indicator microorganisms, were tested for candy, chocolate, and jelly which are easily available and enjoyed around. After dropping each sample on the desk, indoors, and outdoors, it is immediately collected, or washed and collected to confirm the myth of the 3-second rule. Immediately after removing the wrapping paper, each sample was dropped on the desk, indoors, and outdoors, and after 3 seconds from the moment of contact with the surface, and then collected in a sample bag using sterilized sanitary gloves. After the same operation, each sample was rinsed for 5 seconds using sterilized sanitary gloves and sterilized distilled water, and then collected in a sample bag. The number of bacteria detected in non-washing candies was 41 CFU/g at outdoor and the number of bacteria detected in non-washing chocolate was 76 CFU/g at outdoor. The number of bacteria detected in non-washing jellies was 79 CFU/g at outdoor. Coliform group was not detected in all samples. This showed good results at the level of m = 10,000 or less, which is an allowable value suggested in the Food Code. Also, effect of washing on contaminated food was confirmed. This result is remarkably low compared with the microorganism specimens shown in Food Code, and it is confirmed that contamination occurs but not high value. Therefore, the myth of the 3-second rule is true compared to the figures based on Food Code. However, it showed the characteristics of bacteria that could survive and cross-contaminate on dry food surfaces and emphasized the importance of hygiene through food contact to unsanitary surfaces to minimize the risk of food poisoning.

• Journal of the Korean Home Economics Association
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• v.43 no.2
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• pp.19-31
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• 2005

The purpose of this study was to evaluate the microbiological quality and assure the hygienic safety of the Bibimbap production in elementary school foodservice in accordance with the HACCP(Hazzard Analysis Critical Control Point) program. The time-temperature relationship and the microbiological quality(total plate count and coliform bacteria count) were assessed to find the critical control point(CCP) during each of the production phase. In the pre-preparation phase, the risk factors of the raw ingredients exceeded the standard level suggested by Solberg et al. Mungbean starch jelly, egg and Kochujang were satisfactory in that no coliform groups were observed over the standard TPC level. In particular, there was a high the risk of beef from the early stages in terms of the coliform level. In the pre-preparation phase, green pumpkin had more coliform groups than the standard level even after washed, which calls for special attention to washing, sterilization, secondary infection of the handler, and the required time for pre-preparation of raw vegetables. In the cooking phase, the temperature of the soybean sprout and mungbean starch jelly decreased to 42$^{\circ}C$ and 26$^{\circ}C$, respectively, which was within the risk zone. In particular, mungbean starch jelly had a great risk factor even after boiling in hot water. During the storage stage before serving, a lot of ingredients were exposed to poor management of temperature and time and thus exceeded the standard level in the total plate counts. In particular, the microbiological count of beef was five times the standard level. Green pumpkins and soybean sprouts were left at 15-38$^{\circ}C$ that is within the risk zone for a long period of time after they were cooked. It is highly recommended that the time of the storage stage before consumption should be shortened and that proper devices should be used to prevent proliferation of bacteria. The number of TPC of the utensils was satisfactory enough, but the knife used exceeded the standard level and thus was a risk factor of bacteria proliferation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.356-362
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• 1986

This experiment was designed to evaluate effects of freezing and frozen storage on survival of sanitary indicative bacteria in seafoods. Culture of bacteria such as Escherichia coli type I, Citrobacter freundii type I, Klebsiella aerogenes type I and Streptococcus faecalis was inoculated into homogenates of pollack, shrimp, and sardine frozen in a contact plate freezer at $-40^{\circ}C$ and chest freezer at $-20^{\circ}C$, stored at $-20^{\circ}C$, and then survival of the inoculated bacteria was determined over a period of 95 days. Coliform group was highly sensitive to freezing and frozen storage showing survival of about $2\%$ after 95 days of frozen storage at $-20^{\circ}C$, whereas Streptococcus faecalis was relatively resistant with $20\%$ survival rate. The sanitary indicative bacteria count was rapidly decreased in the early stage of frozen storage revealing 90 to $95\%$ loss of coliform group and 40 to $70\%$ loss in case of Streptococcus faecalis after 10 days storage. In determining recovery rate, most probable number (MPN) method gave more reproducible recovery of the tested strain than did the selected agar plate method.

• Microbiology and Biotechnology Letters
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• v.43 no.1
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• pp.31-37
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• 2015

This study was conducted to investigate the bactericidal activity of electrolyzed water (EW) against coliform bacteria on Undaria pinnatifida (UP). The UP was washed with 15% EW, tap water (TW), and distilled water in the following order: 15% EW for 5 and 10 min (1st to 3rd washing process), TW for 1 min, and distilled water for 10 min (3rd to 5th washing process). The washing processes using 15% EW and distilled water occurred a total of 6 times. The number of viable cells, coliform bacteria, and molds in the untreated sample were in the range of 10¹ to 10³ CFU/g. In the case of the UP with 15% EW for 5 min sample, the viable cell counts were reduced by 1-2 log cycles as compared with the untreated sample. The coliform bacteria were not detected except after the 1st EW washing process. Mold counts were not detected in all treatments. In the UP with 15% EW for 10 min sample, the viable cells, coliform bacteria, and mold counts were not detected. In color, there were no significant differences among samples. In sensory evaluation, the UP treated with 15% EW for 10 min (first washing process) got higher scores for color, aroma, and taste than others. These results suggest that the treatment of 15% EW for 10 min is the most effective way to reduce coliform bacteria of the UP.

• Food Science and Preservation
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• v.18 no.1
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• pp.98-102
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• 2011

We evaluated microbial inactivation in chicken cage litter, to ensure microbial safety, using aqueous chloride dioxide. Contamination by coliforms, Escherichia coli, Listeria spp., yeasts and molds, total aerobic bacteria, and Salmonella spp. was detected in fresh cage litter, and microbial populations increased if litters were repeatedly used. Aqueous $ClO_2$ treatment (500 ppm) significantly decreased the populations of coliforms, E. coli, Listeria spp., yeasts and molds, total aerobic bacteria, and Salmonella spp. in all litter samples tested. In particular, aqueous $ClO_2$ treatment on fresh litter reduced the initial populations of coliform, E. coli, Listeria spp., yeasts and molds, and total aerobic bacteria by 4.47, 1.29, 1.23, 3.24, and 5.2 log CFU/g, respectively. In addition, when litters used for 1 and 5 weeks were tested, treatment significantly reduced microbial populations. The results suggest that aqueous $ClO_2$ treatment is useful to reduce microbial hazards in chicken cage litter and to improve the microbial safety of slaughtered chickens.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.6
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• pp.359-364
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• 2005

The distributions of sanitary indicative bacteria and pathogenic bacteria in seawater and four species of farmed fishes, including oliver flounder (Paralichthys olivaceus), black rock fish (Sebastes schlegeli), red sea bream (Pagrus major) and sea bass (Lateolabrax japonicus), collected at fish farms located in the southern coastal area of Korea were investigated from May to October in 2004. The detection rates of fecal coliform and Entirococcus spp. of sanitary indicative bacteria in all samples were $38.9\%$ and $23.8\%$, respectively. The occurrence of fecal coliform was highest of $58.3\%$ in Busan, Geoje and Wando area, followed Yeosu $33.3\%$, Jeju $12.5\%$, Tongyeong $11.1\%$. The occurrence of Enterococcus spp. was highest In Wando area ($45.8\%$), followed by Yeosu ($33.3\%$), Tongyeong ($22.2\%$), Busan ($16.7\%$), Geoje and Jeju ($12.5\%$). The detection rate of fecal coliform was higher than that of Enterococcus spp., except in the Tongyeong area. There was no difference in the detection rate of fecal coliform from May to October, but the detection rate of Enterococcus spp. increased with seasonal warming seawater temperature. Among the pathogenic bacteria, the detection rate of Vibrio alginolyticus ($49.2\%$) in all samples was highest, followed by V. parahaemolyticus ($36.5\%$), Staphylococcus aureus ($6.3\%$), Salmonella sp. ($2.4\%$). However, V cholerae, V. vulnificus and Shigella sp. were not detected in all tested samples. The detection rates of V. parahaemolyticus and V. alginolyticus increased with seasonal warming seawater temperature from May to August.

• Journal of Environmental Health Sciences
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• v.47 no.2
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• pp.182-191
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• 2021

Objective: This study was performed to detect indicator bacteria in drinking spring water samples in Gwangju City and to identify their genus using the VITEK-II system. Methods: The subjects were ten drinking spring water sites in Gwangju. Samples of spring water were taken every month from September 2019 to August 2020. We analyzed for the indicator bacteria Yersinia and microorganisms isolated from the spring water. Result: According to the research results on indicator bacteria, general bacteria in st1-st7 with sterilization facilities in the spring and summer were investigated in the range of 0-2 CFU/mL and 0-12 CFU/mL. In st9, where a sterilization facility was not installed, the most general bacteria were detected (160 CFU/mL). Total coliform and fecal coliform showed unsatisfied rates of 16.7 and 11.1% in spring and 14.7 and 11.8% in summer, respectively. The unsatisfied rates of total coliform for the designated and non-designated spring water facilities were 3.8 and 47.1%, respectively, and for the fecal coliform group they were 2.5 and 35.3%. The difference was confirmed according to the presence of a sterilization facility. Yersinia spp. was not detected in all drinking spring water. Forty-one strains in 25 species were isolated from ten sites. The results classified as major dominant species are Pseudomonas spp. 14.6%, Pantoea spp. 9.8%, Serratia spp. 9.8%, Acinetobacter spp. 9.8%, Citrobacter spp. 7.3%, Bordetella spp. 7.3%, Delftia spp. 4.9%, and Enterobacter spp. 4.9%. Conclusions: Based on the result that various species derived from fecal pollution and artificial pollutants were detected in the non-specified public spring water facilities that many people use, the facilities need institutional complements such as continuous management or complete shutdowns.

• Journal of Environmental Health Sciences
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• v.12 no.2
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• pp.39-48
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• 1986

This study was carried out to investigate the bacterial contamination of Ice Tea sold on the l street in Seoul area. For this, study 81 samples were collected on the street from July to September, 1985 and were examined on the following items. 1. Degree of bacterial contamination. 2. The relation of the occurrence of fecal coliform and salmonella. 3. The change of bacterial contamination in Ice Tea against temperature. As the results of this study, the following conclusion were obtained. 1. The mean count of total viable bacteria by standard plate count was $6.5{\times}10^3$/ml, the mean count of total coliform and fecal coliform by MPN method were $3.4{\times}10^2$/100ml, 5.5/100ml and those of fecal streptococci was $3.2{\times}10^2$/100ml. 2. The mean count of Staphylococcus aureus was 10.5/ml, the isolated rate of salmonella was 7.41%. 3. In relation to the occurrence of fecal colfform and salmonella, salmonella isolated that for values above $10^2$ fecal coliform 100ml. 4. In the change of bacterial contamination in Ice Tea against temperature, the number of total coliform and fecal coliform increased at $25{\circ}$C, decreased at $4{\circ}$C, but fecal streptococci increased at $25{\circ}$C and $4{\circ}$C.