• Korean Journal of Veterinary Service
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• v.24 no.1
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• pp.89-94
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• 2001

In order to investigate the relationship between milk hygienic quality and some environmental factors such as the herd size and types of milking machines, we sampled and examined the level of total bacterial count, coliforms, Staphyococcus aureus, somatic cell counts(SCC) and fat rates in raw milk. of the 84 dairy farms, the prevalence of level on number of standard plate count over 100,000cfu/$m\ell$ and coliforms over 1,000cfu/$m\ell$ in bulk milk were 25.0% and 15.6%, respectively. Also, 2 farms(2.4%) were exceed the level on number of 500cfu/$m\ell$ S aureus in raw milk. The prevalence of dairy herd with first grade of total bacterial count(TBC) according to bucket, pipe line and parlour milking system was 40.0%, 74.0% and 84.0%, respectively. The prevalence of dairy herd with first grade of TBC according to grade 1, 2 and 3 by SCC was 77.8%, 83.2%. and 69.2%, respectively. Therefore, the relationships between hygienic quality in raw milk and the herd size, types of milking machines, were significant. In conclusion, this study could be overemphasized the importance of herd management condition for milk hygienic qualify.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.171-177
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• 1999

The purpose of this study was to serve a standard of the good quality control and shelf-life of food and beverage served from the vending machines. So it was performed to examine the temperature (internal & external environmental, food itself), pH, Aw, POV and microbiological quality of Adlay tea and Wheat noodles served from the vending machines based on storage time in the machines. They were assessed to find the critical control point(CCP) during each of the production, delivery, purchasing phases from the vending machines. The result of this study can be summarized as follows: 1. The temperature of foods inside the vending machines was ranged from 4$0^{\circ}C$ to 45$^{\circ}C$. It was in the range of dangerous zone. The average temperature of food showed 71$^{\circ}C$ for Adlay tea and 74$^{\circ}C$ for Wheat noodles. As a result of measuring pH and Aw, they had potential danger. 2. Even though POV was low, it increased as the time passed. 3. As a result of microbial analysis, it showed that the amount of total plate count and coliforms were increased ten times after 1 day respectively. Wheat noodles' coliform and total plate counts exceeded standard value in 1 day. As a result of food poisoning bacteria, it was negative in sample against Vibrio parahaemolyticus, Salmonella, Staphylococcus aureus.

• Korean Journal of Veterinary Service
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• v.27 no.1
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• pp.7-15
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• 2004

For measuring general bacterial count and Escherichia coli count, the standard plate count was used to conduct a test on 113 cases of pork carcass surfaces from slaughterhouses in Incheon area from January to February 2003. And Salmonella spp, Staphylococcus aureus and Listeria monocytogenes was used to conduct a test on 68 cases of pork carcass surfaces and 76 cases of feces, that is to say, a total of 144 cases. The results were obtained as follows: In the case of general bacterial count, 29 cases(25.7%) were in the range of 100∼999 and 62 cases(54.9%) were in the range of 1,000∼9,999 and 22 cases(19.4%) were in the range of 10,000∼99,999. Meanwhile as regards E coli count, 22 cases(19.4%) were in the range of 1∼9 and 69 cases(61.2%) were in the range of 10∼99 and 22 cases(19.4%) were in the range of 100∼999. On 68 cases of pork carcass surfaces, 7 strains(10.2%) of Salmonella spp, and 12 strains(17.6%) of S aureus were detected and 27 strains(39.7%) of L monocytogenes, respectively. As for the detected Salmonella spp, 6 strains of the B group, 3 strains of S enterica subsp salame and 2 strains of S typhimurium were detected, respectively. On 76 cases of feces, 14 strains(18.4%) of Salmonella spp, and 15 strains(19.7%) of L monocytogenes and 14 strains(18.4%) of S aureus were detected respectively. As for the detected Salmonella spp, 6 strains of the B group, 4 strains of S derby and 8 strains of the C group, 5 strains of S rissen were detected, respectively. All of 42 strains of L monocytogenes were type 1. As a result of conducting a toxin test on the detected S aureus, all of 26 strains were found to be non-toxin.

• Food Science of Animal Resources
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• v.44 no.2
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• pp.372-389
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• 2024

This study investigated the efficacy of ultraviolet-C (UV-C) irradiation in enhancing the quality of raw bovine milk by targeting microbial populations and lipid peroxidation, both of which are key factors in milk spoilage. We categorized the raw milk samples into three groups based on initial bacterial load: low (<3 Log 10 CFU/mL), medium (3-4 Log 10 CFU/mL), and high (>4 Log 10 CFU/mL). Using a 144 W thin-film UV-C reactor, we treated the milk with a flow rate of 3 L/min. We measured the bacterial count including standard plate count, coliform count, coagulase-negative staphylococci count, and lactic acid bacteria count and lipid peroxidation (via thiobarbituric acid reactive substances assay) pre- and post-treatment. Our results show that UV-C treatment significantly reduced bacterial counts, with the most notable reductions observed in high and medium initial load samples (>4 and 3-4 Log 10 CFU/mL, respectively). The treatment was particularly effective against coliforms, showing higher reduction efficiency compared to coagulase-negative staphylococci and lactic acid bacteria. Notably, lipid peroxidation in UV-C treated milk was significantly lower than in pasteurized or untreated milk, even after 72 hours. These findings demonstrate the potential of UV-C irradiation as a pre-treatment method for raw milk, offering substantial reduction in microbial content and prevention of lipid peroxidation, thereby enhancing milk quality.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.259-266
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• 2015

Observed trends in climate change, globalization and an aging population have an effect on public health conditions in Korea, prompting a reevaluation of current environmental regulations. In this study, we evaluated the performance of the total coliform (TC) standard, which is the only microbiological standard in the current regulation regime for hot spring water, by estimating correlation with the presence/absence of Legionella, a non-fecal opportunistic pathogen with heat-tolerance. Microbiological data in 7 studies that surveyed Legionella in hot spring waters were subjected to meta-analyses with the odds ratio (OR) as the effect size. The presence/absence of Legionella was significantly correlated to TC levels [OR = 3.1(1.5–6.4, 95% CI), p = 0.002]. Due to there being no direct explanation as to the reason for the occurrence of TC, mesophilic fecal bacteria, being coupled with Legionella presence, the mechanism of the correlation between the two kinds of bacteria was further investigated. Legionella presence was more prevalent with a high heterotrophic plate count [HPC; 4.0(2.2–7.2); p < 0.001] and water temperature [4.3(1.4–13.6), p = 0.011] when the temperature range was <40℃. However, it was reverse-correlated with water temperature when the temperature was >50℃ [0.2(0.1–0.4), p < 0.001]. Therefore, bacterial standing crops in hot spring waters appear to be determined by water temperature in general, and this forces TC and Legionella levels be correlated. In accordance with this relationship, HPC rather than TC reflect the levels of non-fecal contamination better. Therefore, employing HPC as the sole microbiological standard, or adding HPC into the current standard of hot spring water assessment, is suggested as a proactive measure to prevent health issues arising from contamination.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.178-184
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• 1996

Dryfilm method by using 3M Petrifilm$^{TM}$ has been examined to replace conventional agar method for isolation of microorganisms from foods. The objectives of the present study were to evaluate suitability of dryfilm method as a microbial isolation method and to determine the effect of antimicrobial agent on dryfilm for isolation of microorganisms from foods. Five different foods, milk, ground beef, fishery surimi, Takju and wheat flour were used to isolate the natural microflora in foods and the inoculated Escheri chia coli. Standard method agar (SMA, Difco) and Petrifilm$^{TM}$ aerobic count (PAC, 3M) were used to isolate total microorganisms from foods. Violet red bile agar (VRBA), brilliant green lactose bile (BGLB) broth and Petrifilm$^{TM}$ coliform count (PCC, 3M) were used to isolate coliforms from foods. E. coli broth (EC broth) and Petrifilm$^{TM}$ E. coli count (PEC, 3M) were used to isolate E. coli from foods. Acidified potato dextrose agar (APDA) and Petrifilm$^{TM}$ yeast & mold count (PYMC, 3M) were used to isolate yeasts and molds from foods. Total aerobic plate counts isolated from five different foods by SMA and PAC (3M) were riot significantly different each other at P<0.05 level and were highly correlated each other ($\geq$0.96). Mugwort extract as an antimicrobial agent did not affect microbial enumeratiion of Dryfilm. Significantly higher number of coliform colonies were formed on VRBA than PCC (3M) from ground beef, but they were not significantly different in coliform colonies from milk samples. PCC (3M) and BGLB were not significantly different for enumeration of coliforms in milk and beef samples. Significantly higher number of E. coli were isolated by EC broth than PEC from ground beef, but these were not significontly different for enumeration of E. coli from milk. Yeast and mold counts isolated from Takju and wheat flour by APDA and PYMC (3M) were not significantly different at P<0.05 level. These data indicate that dryfilm method by using 3M Petrifilm$^{TM}$ can be successively used as an alternative to conventional agar method for enumeration of microorganisms in various foods.

• Food Science of Animal Resources
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• v.21 no.2
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• pp.149-155
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• 2001

The aims of this study were to examine contamination sources and provide the basic data in establishment of sanitary standard for raw pork meat. From \"Random sampling(I)\", initial total plate counts of post-slaughter samples for the group A, B and C were 1.5${\times}10^4$cfu/$textrm{cm}^2$, 5.5${\times}10^5$cfu/$textrm{cm}^2$ and 1.8${\times}10^4$cfu/$textrm{cm}^2$, respectively, and of post-prechilling samples for the group A, B and C were 1.0${\times}10^4$cfu/$textrm{cm}^2$, 4.6${\times}10^5$cfu/$textrm{cm}^2$ and 2.5${\times}10^4$cfu/$textrm{cm}^2$, respectively. Initial total plate counts of post-transportation samples for the group D, E and F did not increased, as did the group A, B and C. From \"Normal sampling(II)\", initial total plate counts of post-slaughter, post-prechilling, post-transportation and post-2 days preservation samples were 7.3${\times}10^4$cfu/$textrm{cm}^2$, 9.6${\times}10^4$cfu/$textrm{cm}^2$, 2.0${\times}10^5$cfu/$textrm{cm}^2$ and 2.5${\times}10^5$cfu/$textrm{cm}^2$, respectively. From \"Clean sampling(III)\", initial total plate counts of post-slaughter, post-prechilling, post-transportation and post-2 days preservation samples were decreased to 7.0${\times}10^2$cfu/$textrm{cm}^2$, 7.5${\times}10^2$cfu/$textrm{cm}^2$, 8.5${\times}10^2$cfu/$textrm{cm}^2$ and 5.5${\times}10^3$cfu/$textrm{cm}^2$, respectively, compared with "Normal sampling(II)". No E. coli O157:H7, Staphylococcus aureus and Salmonella were detected at each sampling step. Consequently, a slaughter method like "Clean sampling(III)" showed a better sanitary effect to low total plate counts of 10$^2$∼10$^3$times, compared with "Normal sampling(II)". The one of contamination sources for raw pork meat was at a slaughtering step, and "Clean sampling" method may be considered as the one of sanitary standards.

• Journal of Food Hygiene and Safety
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• v.21 no.2
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• pp.70-75
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• 2006

Of 111 bacterial isolates on 32 dried salted marine products in Garak wholesale market.72 strains were coliforms, and 12 were staphylococcus spp. etc. In average, humidity 17.28%, ashes 4.92%, standard plate count $1.1{\times}10^7$ CFU/ml, coliforms count $9.0{\times}10^3$ CFU/ml, staphylococcus spp. $5.4{\times}10^6$ CFU/ml respectively. Of 72 coliforms, it was isolated by 21 Pantoea spp, 14 Enterobacter cloacae and, 13 Ranella aquatilis, etc. and of 12 Staphylococcus spp. 4 staphylococcus xylosus was the most.

• Culinary science and hospitality research
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• v.23 no.6
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• pp.20-26
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• 2017

To guarantee the safety of rice cake production, the Hazard Analysis Critical Control Points system was applied to the production process. The purpose of this study was to analyze the microbiological hazards of the manufacture of rice cakes, and establish critical limits in the process of the manufacturing rice cakes. To control the microbiological hazards, the sterilization process was set to a critical limit. The process of manufacturing rice cakes can reduce these microbiological hazards during the steaming process. A microorganism test for each specimen was conducted three times and compared with before and after steaming processes. The finished product was conducted by microbiology experiment and the validity of the steaming process was verified. The results were determined to be capable of reducing the biological element of Critical Control Point via the steaming process. Microbiology such as aerobic plate count, coliform, Escherichia coli(E. coli), Listeria monocytogenes, Enterohemorrhagic E. coli, Salmonella spp., Bacillus cereus, Staphylococcus aureus and Clostridium perfringens was evaluated by the experimental method of Korean Food Standards Codex. Aerobic plate count was reduced by steaming process, and no microorganism were detected. All rice cakes in the finished product were judged to be safe for both the Escherichia coli and general bacteria. In conclusion, it suggested that a HACCP plan was necessary for management standard and systematic approach in the establishment of critical limit, problem resolution, verification method, education, and records management. Based on this study, it is intended to provide a baseline for improving quality control standards and improving hygiene levels for small manufacturers.

• Journal of Korean Society on Water Environment
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• v.36 no.2
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• pp.148-152
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• 2020

The quantitative accuracy of dry rehydratable film method was compared with the standard culture method to analyze the applicability of dry rehydratable film in the total aerobic bacteria test for water. The materials used in this study were 500 cases of water and were tested according to the Korean official test method for drinking water. The mean value of the total aerobic bacteria in plate count agar(PCA) and MC-Media Pad AC(MAC) were 2.6 ± 1.1 Log cfu/mL and 2.6 ± 1.2 Log cfu/mL. The p value and correlation coefficient(R²) were 0.933 and 0.9985 between the PCA and MAC, respectively, indicating no significant difference and very high correlation. According to the water types, the p value and R² were 0.887 and 0.9911 in the PCA and MAC. In the purified water, the p value was 0.973 and R² was 0.9934 in the PCA and MAC of other water. In each type of water, there were no significant differences between the PCA and MAC, and the correlation was very high. Thus, it is suggested that the MAC would be available for total aerobic bacteria test for water.