• 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.

• Preventive Nutrition and Food Science
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• v.15 no.3
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• pp.239-243
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• 2010

The antimicrobial effects of a commercially available, buffered sodium citrate (BSC) were evaluated for the reduction of total aerobic bacteria count, Salmonella Typhimurium, Escherichia coli O157:H7, Listeria monocytogenes and Staphylococcus aureus in a liquid medium and ground beef. BSC at 0, 1, 2 and 4.8% (wt/vol) or 0, 3, and 4.8% (wt/wt) was mixed into inoculated brain heart infusion (BHI) broth and ground beef (80% lean), respectively. BSC at concentrations of 1 and 2% did not inhibit growth of the pathogens tested in BHI broth. E. coli O157:H7 in BHI broth with 4.8% BSC was significantly reduced (p<0.05) by 3～4 log CFU/mL compared with the control for up to 4 days. At 4.8%, BSC treatment of ground beef most significantly reduced (p<0.05) total aerobic count and E. coli O157:H7 by 2.1 and 2.0 log CFU/g, respectively. This study indicates that the legally allowable level of 1.3% (wt/wt) BSC is not effective for reducing the pathogens tested in ground beef stored at $7^{\circ}C$.

• Journal of Applied Biological Chemistry
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• v.51 no.3
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• pp.128-135
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• 2008

A total of 142 samples comprising vegetables, soil, and water collected from different agricultural farms (five provinces) were analyzed for total aerobic bacteria (aerobic plate count [APC]), Bacillus cereus, Escherichia coli, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus. The average of total APC in all the samples ranged from $4.72{\times}10^5$ to $8.62{\times}10^8\;CFU/g$ (mL). The prevalence of B. cereus, E. coli, L. monocytogenes, S. spp., and S. aureus for all samples was 17.60%, 2.11 %, 1.4%, 0%, and 2.11 % respectively, and their counts averaged to $4.87{\times}10^4\;CFU/g$ (mL), $4.34{\times}10^3\;CFU/g$ (mL), $2.15{\times}10^2\;CFU/g$, 0 CFU/g, and $3.12{\times}10^3\;CFU/g$ respectively. Among the 3 different types of samples, 6 vegetables (10.34%), 24 soil (38.70%), and 3 water (13.64%) samples were found to be positive for bacterial pathogens. The result showed that the occurrence of bacterial pathogen in the samples analyzed was low. Further time to time monitoring and need to wash of raw agricultural products is recommended.

• Journal of the Korean Home Economics Association
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• v.25 no.4
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• pp.57-62
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• 1987

To obtain basic data for the decvelopment of Kimchi preservation method, optimal ripening Kimchi was air-packaged with polyethylene bag, and followed by the microbiological, firmness and sensory evaluations during storage at 5$^{\circ}C$. 1. Total aerobic count increased in the beginning of storage and then decreased slowly as the number of total Lactic bacteria(anaerobe) in creased. 2. Textural parameters were remarkably changed according to the elapse of storage period. 3. Sensory evaluation showed that the score was decreased considerably 10 days after storage.

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.1
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• pp.1-13
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• 1997

The fermentative conversion of food wastes into feed was investigated by seeding of mixed inoculum YM (Youngjin Environmental co.), and thermotolerant yeast Kl. marxianus. For 6 days' fermentaion, the fermentation method of 2 days' aerobic followed by 4 days' anaerobic was better for the production of organic acids and increasing total microbial population than 6 days' continuous aerobic or anaerobic fermentation. By seeding YM, the total microbial count increased about 100 times of the control group. In addition, Kl. marxianus seeding together with YM increased total viable cell count, but did not increase yeast count significantly.

• Journal of Environmental Health Sciences
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• v.40 no.1
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• pp.63-70
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• 2014

Objective: The purpose of this study was to investigate the occurrence of indicator organisms in essential sanitary ware in public restrooms. Methods: Twelve public restrooms were randomly selected. Samples at three locations (toilet seat, toilet flush handle/lever, and faucet handle) in the restrooms were collected with moistened-sterile cotton swabs and applied to media in order to determine aerobic colony count (ACC), total coliforms, and Escherichia coli. Results: Most of the samples taken in summer showed a higher level of ACC than those taken in winter (p<0.05). Female restrooms showed higher ACC levels on faucet handles and male restrooms on toilet flush handles/levers (p<0.05). Overall, faucet handles contained the greatest level of ACC, followed by toilet seats, whereas the least load was found on toilet flush handles/levers. The ACC level of samples in the restrooms in public parks, subway stations, and educational institutions varied. Total coliforms were identified in about 20% of toilet seats and faucet handles in male restrooms and faucet handles in female restrooms in summer. These locations were also the sites of positive results of E. coli isolation. Conclusions: The public restrooms were significantly more contaminated in summer than in winter. Overall, the most contaminated locations in the restrooms were toilet seats in male restrooms, and faucet handles in female restrooms. Poor hygienic status was indicated by the positive results of total coliforms and E. coli on samples from some sites. Therefore, sanitary control of restrooms should be improved. These results should be confirmed in a larger study that includes more public restrooms.

• Journal of the Korean Dietetic Association
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• v.12 no.2
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• pp.172-184
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• 2006

This study was aimed to provide safety management guidance by evaluating the microbial quality of cooked dried-seafoods in school foodservice operations. Nineteen seafood items were collected from six elementary schools, those were dried-anchovy, dried-seaweed and dried-fish, which were classified as cooking process. The temperatures at receiving and after cooking were measured and the analyses of cooking processes and microbial quality were performed. The temperatures of all foods after cooking were higher than the temperature limit of $74\^circC$. The number of total aerobic bacteria and S. aureus in dried-anchovy over the limit of $10^5$ and even the level of S. aureus was found to be unsatisfactory. The count of total aerobic bacteria was 2.1x$10^8$ CFU/g and the number of total aerobic bacteria after cooking was over the limit in one school. The level of E. coli (3.1x$10^3$ CFU/g) was over the limit at one school and the number of S. aureus (1.2×$10^4$ CFU/g) was considered as unacceptable. Dried- tangle and green laver were contaminated with total aerobic bacteria showing the over the limit. The numbers of total aerobic bacteria in dried- filefish, pollack and squid were 4.3x$10^6$, 3.4x$10^6$-3.9x$10^7$ and 4.6x$10^5$-4.1x$10^7$ CFU/g, respectively, which were in acceptable or unsatisfactory level. The E. coli in dried- filefish and pollack were over the limit. The total aerobic bacteria levels, 4.6x$10^5$-1.5x$10^6$ CFU/g in dried-pollack and 8.0x$10^5$-2.2x$10^7$ CFU/g in dried-squid, were over the limit after cooking except dried-filefish. The E. coli levels, 4.3x$10^3$ CFU/g in dried-filefish and 2.5x$10^2$ CFU/g in dried-pollack, were over the limit of $10^2$ CFU/g. The numbers of Enterobacteriaceae were either acceptable (3.3x$10^3$ CFU/g) or unsatisfactory (1.6x$10^4$ CFU/g) level in dried-pollack. S. aureus was unsatisfactory level (6.5x$10^4$ CFU/g) in dried-filefish while unacceptable in dried-pollack both before and after cooking. Unacceptable levels of S. aureus, 2.4x$10^4$ and 1.3x$10^5$ CFU/g were found from two schools, respectively. These results suggest that the contamination of raw materials and the seasonings added after cooking should be controlled to manage the microbial safety of cooked dried-seafoods.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.12
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• pp.1733-1738
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• 2017

Objective: Different dry-aging methods [traditional dry-aging (TD), simplified dry-aging (SD), and SD in an aging bag (SDB)] were compared to investigate the possible use of SD and/or SDB in practical situations. Methods: Sirloins from 48 Hanwoo cows were frozen (Control, 2 days postmortem) or dry-aged for 28 days using the different aging methods and analyzed for chemical composition, total aerobic bacterial count, shear force, inosine 5′-monophosphate (IMP) and free amino acid content, and sensory properties. Results: The difference in chemical composition, total aerobic bacterial count, shear force, IMP, and total free amino acid content were negligible among the 3 dry-aged groups. The SD and SDB showed statistically similar tenderness, flavor, and overall acceptability relative to TD. However, SDB had a relatively higher saleable yield. Conclusion: Both SD and SDB can successfully substitute for TD. However, SDB would be the best option for simplified dry-aging of low-marbled beef with a relatively high saleable yield.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1738-1742
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• 2003

The whole plant of crop maize was chopped and ensiled in double-layered polyethylene bags to determine the influence of residual sugar on the fermentation of lactic acid and aerobic stability by L. buchneri in whole crop maize silage made in airstress condition. There were a total of six treatments used in this experiment as follow: added 25 g de-mineralised water per kg chopped maize serving as control (con), 37.5 g glucose solution containing 12.5 g glucose ($g_1$), 75 g glucose solution containing 25 g glucose ($g_2$), 25 g, L,.buchneri suspension intended for $10^6$ cfu $g^{-1}$ (L.b.), $g_1$+L.b. and $g_2$+L.b. All silos were opened at day 91 after ensiling for measuring the pH values, microbiological enumeration, fermentative products and aerobic stability. The dry matter loss increased significantly (p<0.01) due to inclusion of sugar or L. buchneri. The lower lactic acid concentrations were observed (p<0.01) in silages inoculated with L. buchneri only or in combination with sugar addition than the correspondent uninoculated silages. Compared with control silage, ethanol production was about 3 or 6-fold higher due to addition 12.5 or 25 g glucose per kg chopped maize at ensiling. The silages added with sugar contained less acetic acid concentration (p<0.01) than control, but silages inoculated with L. buchneri showed the contrary effects (p<0.01) at different sugar levels. No butyric acid was found in uninoculated silages, silages inoculated with L. buchneri. producted more propionic acid, 1-propanol and butyric acid. Lactic acid bacteria counts increased markedly (p<0.01) due to inoculation with L. buchneri, whereas it was reduced (p<0.01) by added sugar. No significant difference was observed in count of yeast, but inoculation with L. buchneri shows a decreasing trend. Mould count in all silages was less than 2 (log cfu $g^{-1}$). The added sugar had negative effects on aerobic stability of maize silage made under air-stress conditions, whereas inoculation with L. buchneri improves (p<0.01) the aerobic stability.

• Journal of Food Hygiene and Safety
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• v.37 no.3
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• pp.181-188
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• 2022

Despite the recent increase in the consumption level of the processed meat-byproducts, the health and safety issue has consistently been raised in the processes of production, distribution and consumption. The purpose of this study is to analyze and evaluate the microbiological hazard elements in the Korean sausage, "Sundae," to present not only the safety standard of meat by-product vendors based on HACCP (Hazard Analysis Critical Control Point), but also the quality control criteria and sanitary arrangements of small manufacturers. For the study, the microbiological hazards in 24 raw materials, 7 manufacturing processes, 40 facilities and tools, 17 workplace environment, and 12 workers were analyzed. The analysis revealed the hazardous elements in the initial stages with 6.28 and 4.07 log CFU/g of total aerobic count and coliforms, respectively, detected from the porcine blood and 3.23 log CFU/g of coliforms from the porcine small intestines. The result also showed that the total aerobic counts and coliforms in the process of mixing and filling process exceeds the standards in the hygiene guidelines by Natick with the total aerobic counts of 5.23, 5.45 log CFU/g, and the coliforms of 3.25, and 3.31 log CFU/g, respectively. Although the detected total aerobic count and the coliforms in the filling and washing rooms exceeded the standards, it was found that the total aerobic count was significantly reduced by 98% after cleaning and disinfecting and no coliforms was detected in any process thereafter. In order to achieve high level of safety in the manufacturing processes of Sundae, the separation of washing and disinfection room from the other sections and the sanitation control of the workers must be preceded, along with strict monitoring in the storage and distribution processes. The study raises necessity for additional studies for the safety evaluation of the processed meat-byproducts and further researches on the validity of the critical limits.