• Journal of Environmental Health Sciences
• /
• v.32 no.1 s.88
• /
• pp.77-88
• /
• 2006

This study were conducted to investigate the microbial contamination level in 5 tomato farms in Western Gyeongnam. A total of 130 samples was examined for sanitary indicator bacteria, such as aerobic plate count (APC), coliforms, and Escherchia coli, and pathogenic bacteria such as E. coli O157:H7, Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes. APC and coliform count ranged $0\~6.62\;and\;0\~4.52 log_{10}\;CFU/(ml,\;g,\;100\;cm^2,\;hand)$, respectively, and $32.5\%$ were contaminated with E. coli. Especially, most of the samples from employees are high as above $4.0\;log_{10}\;CFU/(ml,\;g,\;100\;cm^2,\;hand)$ in APC. S. aureus, detected at $10.7\%$, was found in employees' hands, irrigation water, and hydroponic solution. whereas E. coli $O157:H7$, Salmonella spp, and L. monocytogenes were not detected. These results will provide fundamental microbiological information for introduction of good agricultural practice (GAP)system in tomato farms.

• Journal of Food Hygiene and Safety
• /
• v.19 no.2
• /
• pp.60-65
• /
• 2004

120 samples of ready-to-eat salad product were purchased at department stores, marts and family restaurants in metro area. Coliform bacteria and food borne pathogenic bacteria were isolated from these samples. In 73 samples among the 120 salad product samples, coliform bacteria and food borne pathogenic bacteria were detected by 60.8％ of isolated rate. Salad were classified into organic and non-organic salad. According to a salad type, salad were classified into vegetable salad and mixed vegetable salad with fried chicken and extra food. According to a packing type, packed salad product and salad-bar product were classified. After the classification, the results of each cases were compared. There is no statistical relation between cultivation or packing methods and contaminated bacteria. But the incidence number of microbial strains was significantly different between vegetable salad and mixed vegetable salad(p＜0.005). In vegetable salad, more various strains were detected. E. coli was isolated in 10 cases among the 90 cases in non-organic vegetable and in 7 cases among the 30 cases in organic salad. Food borne pathogenic bacteria were isolated in non-organic vegetable salad product. Staphylococcus aureus was isolated in 4 cases of vegetable salad product and Salmonella spp. isolated in 1 case. After 5 times examination of each 4 market products, the total number of aerobic bacteria was average 4.8$\pm$0.19 log cfu/g. One sample from this product, saline and a detergent for vegetable were used for 3 minutes to notice the effect. As a result, when saline was used 5 times and detergent for vegetable was used 1 time, bacterial contamination was decreased up to 95.5％.

• Journal of Food Hygiene and Safety
• /
• v.34 no.6
• /
• pp.526-533
• /
• 2019

The purpose of this study was to investigate hazardous microorganisms in mixed baby leafy vegetables and various baby leafy vegetables used as raw materials for fresh-cut produce in spring and summer. To estimate microbial loads, a total of 298 samples including 181 samples of mixed baby leafy vegetables purchased in a Korean market and 117 samples of various baby leafy vegetables from distribution companies were collected. Fecal indicators (coliform and Escherichia coli) as well as food-borne pathogens (E. coli O157:H7, Salmonella spp., Staphylococcus aureus) were enumerated. As a result, the mixed baby leafy vegetable samples showed significantly higher (P<0.05) coliform bacteria numbers in summer (5.59±1.18 log CFU/g) compared to spring (3.60±2.53 log CFU/g). E. coli was detected in 1.3% (1/79) and 42.2% (43/102) of samples collected in spring and summer, respectively. Only one sample collected from a market in spring was contaminated with S. aureus. In the experiment with baby leafy vegetables, the number of coliforms detected in baby leafy vegetables cultivated in soil in spring was 1.15±1.95 log CFU/g, and that in summer was 4.09±2.52 log CFU/g. However, the number of coliforms recovered from baby leafy vegetables cultivated in media was above 5.0 log CFU/g regardless of season. Occurrences of E. coli were 44.4% (12/27) and 19.0% (4/21) for baby leafy vegetables cultivated in soil and media, respectively. However, E. coli O157:H7 and Salmonella spp. were not detected. These results are in relation to microbial loads on mixed baby leafy vegetables associated with raw materials. Therefore, it is necessary to develop and implement hygienic practices at baby leafy vegetable farms to enhance the safety of fresh produce.

• Korean Journal of Food Science and Technology
• /
• v.37 no.2
• /
• pp.294-300
• /
• 2005

Contents of total aerobic bacteria, coliform, Escherichia coli, yeast, mold, and Staphylococcus aureus in meat, dairy, and fishery products were analyzed by dry rehydratable film method using 3M $Petrifilm^{TM}$ and compared against those obtained through conventional method. Two methods showed high correlations of 0.990-0.999, 0.975-0.999, 0.979-0.987, 0.978-0.984, and 0.999 for total aerobic bacteria, yeast and mold, coliform, E. coli, and S. aureus, respectively; therefore, dry rehydratable film method using 3M $Petrifilm^{TM}$ offers acceptable alternative to conventional method for enumeration of microorganisms in meat, dairy, and fishery products.

• Journal of fish pathology
• /
• v.4 no.1
• /
• pp.15-21
• /
• 1991

The environmental factors and the distribution of coliform group were investigated in Suyeong bay on the summer, 1989. The ranges of environmental factors were as follows : Dissolved oxygen $0.54{\sim}6.82m{\ell}/{\ell}$, COD(Chemical Oxygen Demand) 0.28~9.84ppm, Salinity 14.7~33.5%, Nitrite $0.13{\sim}20.49{\mu}g-at/{\ell}$, Nitrate $0.89{\sim}62.77{\mu}g-at/{\ell}$, Ammonia $3.81{\sim}246.98{\mu}g-at/{\ell}$, Silicate $6.12{\sim}177.5{\mu}g-at/{\ell}$. The coliform group ranged $10^4{\sim}10^5/100m\ell$ in the mouth and it was decreased in the open sea. Among the composition of coliform group, E. coli I type was dominent at distance area. The correlation between coliform group and ammonia was r=0.629. There were negative correlation between salinity, dissolved oxygen and coliform group during study period.

• Food Science of Animal Resources
• /
• v.36 no.5
• /
• pp.594-600
• /
• 2016

This study aimed to examine the microbial contamination levels in livestock products at retail stores. Beef, pork, and chicken samples from raw materials and final products were obtained between January and December 2015. All homogenized meat samples (25 g) were tested for the aerobic plate count (APC), coliform count (CC), and Escherichia coli count (E. coli). The highest APCs in meat samples, by month, at retail shops were obtained in September, followed by July, May, and October (p<0.001). However, APC was the highest in summer and the lowest in winter (p<0.001). Average APCs for beef, pork, and chicken samples were 2.90, 3.19, and 3.79 Log CFU/g, respectively (p<0.05). A comparison between different months revealed that, CC levels in meat samples ranged from 0 to 1.13 CFU/g, and the highest CC was obtained in August (p<0.001). By season, the highest CC was found in the summer, followed by autumn, and spring (p<0.001). All meat samples were negative for E. coli. The average log₁₀APC and CC for all samples was 3.10 and 0.37 Log CFU/g, respectively. Furthermore, there was a direct correlation between the season and coliform presence (p<0.001). There was also a positive correlation between the APC and CC (r = 0.517, p<0.001). The microbiological APCs for livestock products were in most cases below 10⁶ CFU/g.

• Journal of Korean Society on Water Environment
• /
• v.25 no.3
• /
• pp.363-369
• /
• 2009

We developed the Eco medium for Escherichia coli and total coliforms, which was modified by Violet Red Bile (VRB) medium, and derived the standard curve of exponential phase at $OD_{410}$ by using type strains such as E. coli ATCC11303, Enterobacter cloacae KCTC2361, Klebsiella pneumoniae KCTC2241, and Citrobacter freundii KCTC2359. Also, we used total 93 samples of spring and stream water to compare the detection ability of total coliforms between the method using Eco medium and such as most probable number (MPN), and plate count methods. As a result, the qualitative analysis of E. coli and total coliforms using Eco medium contained ortho-nitrophenyl-$\beta$-galactoside (ONPG) and 4-methylumbelliferyl-$\beta$-D-glucuronide (MUG) was same as those of Korean standard methods (Colilert kit). And the colony forming unit (CFU) detected in Eco medium was similar to those of result from MPN and plate count methods. Moreover, the agreement, sensitivity, and specificity of the developed kit was more than 97.5% in comparison with Colilert kit for 350 samples. Thus, the Eco medium can be used both qualitative and quantitative analysis of E. coli and total coliforms.

• Fisheries and Aquatic Sciences
• /
• v.7 no.2
• /
• pp.64-69
• /
• 2004

A bacteriological survey for 20 large grocery stores (M 1 to M20) in Korea was investigated for one year. The average detection rate of Esherichia coli was $22\%$ (166/763) for 7 kinds of ready-to-eat food through the year, where each grocery store and each type of food showed different detection rates. Eleven grocery stores showed lower detection rates, while 9 grocery stores showed a higher than average rate. Especially, M3 showed a rate that was twice as high as the average and one which was 7 times higher than M14, which had the lowest rate of $6\%$ E. coli detection. The detection rate for each type of food was: $38\%$ (41/109) for Kimbop, $31\%$ (34/109) for vegetable salad, $19\%$ (21/109) for bean-curd, $18\%$ (20/109) for the cooked materials used in making Kimbop, $17\%$ (19/109) for Hoe (sliced raw fish) and Sushi (Japanese vinegared rice delicacies), and $11\%$ (12/109) for cooked pork hock. During the summer, the E. coli detection rate averaged $43\%$ (71/166), which was twice as high as other seasons. Most (89/100) of the food contacting surfaces contained more than the critical limit $(1.3\;log_{10}\;CFU/10cm^2)$ of aerobic viable cell counts (AVC). The $log_{10}$ AVC and $log_{10}$ coliform count (CC) of 218 meat samples (beef, pork, and chicken) ranged between 4.6-7.1 CFU/g and 1.9-6.4 CFU/g, except for 41 meat samples $(19\%)$ which were found to contain no coliform. There was a definite correlation between the $log_{10}$ AVC and $log_{10}$ CC, and the values of $log_{10}$ CC made a more accurate straight than the $log_{10}$ AVC, which are variable. From these results, it is suggested that a detection rating of less than 2.1 CFU/g of $log_{10}$ CC (correspond to 5.0 CFU/g of $log_{10}$ AVC) is the critical point of freshness, and a rating of more than 6.3 CFU/g of $log_{10}$ CC (correspond to 7.0 CFU/g of $log_{10}$ AVC) can be considered an initial spoilage point.

• Korean Journal of Microbiology
• /
• v.3 no.1
• /
• pp.7-10
• /
• 1965

Higher number in colony counts in coliforms, total aerobes, and anerobes was obtained from marketable soy-bean mash than front that in fermented tank. The ratio between coliform contamination and total viable cells was higher in red pepper mash than in soy-bean mash. E. coli, contaminated in soy-bean mash persisted longer at low temperature ($0^{\circ}C$-$^5{\circ}C$) than at room temperature and they vanished after seven days of storage at room temperature. At 30.deg.C and 35.deg.C, these organisms were more effected than at room temperature. E. coli cells, inoculated in red pepper mash, were not recovered at room temperature after five days incubation. Soy-bean mash, completely fermented at normal conditions, were detected to contain $10^8$- $10^9$ organisms per gram of sample. On the contrary, marketable soy-bean mash were found to have more than 10$^{9}$ per gram samples. Since samples were found to have more than $10^9$ aerobes and anaerobes per gram, contamination of coliforms seemed to be apparent.

• Journal of Food Hygiene and Safety
• /
• v.12 no.4
• /
• pp.354-360
• /
• 1997

This study was intended that the biochemical patterns, bioserological characteristics, resistance of antibiotics, and transferable resistance patterns of 35 Dscherichia coli strains from 79 fish and shellfish samples in marine markets from August to October, 1995. The Standard plate count, coliforms and fecal coliforms were also counted in the 79 cases and analysed the correlationship each other. Geometric means of Standard plate count in seawater fish, shellfish, mollusca and crustacean were 1.4$\times$105 CFU/g, 4.0$\times$105 CFU/g, 2.4$\times$105 CFU/g, 4.7$\times$105 CFU/g, and those of coliforms were 1.3$\times$103 CFU/g, 4.8$\times$103 CFU/g, 8.9$\times$102 CFU/g, 5.8$\times$103 CFU/g. There were no fecal coliforms in the fish and mollusc. However, the geometric means of coliforms in the shellfish and crustacean (1.1$\times$101 CFU/100g, 10 CFU/100 g) were less than those of fish and mollusca. The important biochemical characteristics of E. coli distinguished from the shellfish and crustacean were motility, ornithine decarboxylase, mucate, esculin. The fermentative properties of E. coli were also sucrose, salicin, sorbitol, and raffinose. Of 35 isolates of E. coli, 13 strains (37.1%) showed the pathogenic O antisera, which were O:27 3 strains (23.1%), ):159 2 strains (15.4%) and ):148, O:119, O:142, O:158, O:136, O:18, O:128, and O:168 1 strain (7.7%),respectively.