• Korean Journal of Veterinary Service
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• v.23 no.2
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• pp.105-112
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• 2000

This survey was conducted to evaluate the microbiological quality of raw beef and pork products from January to December in 1999. A total of 107 beef and 157 hog carcasses were collected from two abattoirs located in Seoul. The result showed that beef carcasses had an average bacterial loading around 139,000 bacteria/$\textrm{cm}^2$ of carcass surface, indicating a little bit higher count than the results reported in USA and Australian meat. However, overall hygienic status was found to be acceptable for all examined carcasses because 84.4% of product rated excellent, good or acceptable comparable to USA of 91.6% and Australia of 88%. The analysis of data on overnight-chilled to weekend-chilled carcasses indicated that the microbiological growth occurred in the chiller during the weekend chill with increases in total viable count from 130,000cfu/$\textrm{cm}^2$ to 400,000cfu/$\textrm{cm}^2$. Qualitative testing for escherichia coli, EC + MUG was used as a most probable number (MPN) method along with the petrifilm method. The average of MPN/$\textrm{cm}^2$ of E coli biotype 1 was 29MPN/$\textrm{cm}^2$ for beef carcasses and 1,100 MPN/$\textrm{cm}^2$ for hog carcasses, respectively. However, 41% of beef and 16.3% of hog carcasses were shown to be less than < 3 MPN/$\textrm{cm}^2$ in E coli biotype 1 examination. Although salmonella enteritis, S typhimurium and E coli O157:H7 were all negative, listeria monocytogenes was recovered from only one hog surface samples of the 89 carcasses tested.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.194-199
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• 2001

This study was designed to compare the effectiveness and applicability of the HApS$^{TM}$ (Hazard Analysis process System; HUKO, Seoul, Korea) based on Petrifilm$^{TM}$ (3M, St. Paul, MN, USA) with the AOAC (the Association of Official Analytical Chemists) standard total aerobic count (TAC) method and coliform count (CC) method for meat products. The comparisons were carried out using 230 meat samples collected from various retailers: 80 pork samples, 80 chicken samples, and 70 beef samples. In the comparison of the correlation coefficient (r) between conventional method and HApS$^{TM}$ method by a linear regression analysis, the correlation coefficients in total microorganism were 0.97767, 0.90712, and 0.95594 in pork, beef, and chicken samples, respectively. The correlation coefficients in coliform count were 0.82062, 0.94833, and 0.96839 in pork, beef and chicken samples, respectively. All the independent t-test on measurement values between conventional method and HApS$^{TM}$ method represented no significant differences in the means between two methods at the 0.05 of significance level($\alpha$=0.05). Based on the high correlation between HApS$^{TM}$ and the AOAC standard methods in the TAC and CC, it might be compatible to employ the HApS$^{TM}$ method to measure the microbial contamination in livestock products. HApS$^{TM}$ method was simpler and less time-consuming in sample preparation and procedures faster than the conventional method. These results suggested that the HApS$^{TM}$ method could be substitute for the conventional methods in the analysis of microbial contamination measurement in meat products.n meat products.

• Journal of Food Hygiene and Safety
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• v.31 no.6
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• pp.393-398
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• 2016

The objective of this study was to isolate pathogenic Escherichia coli from fresh vegetables with selective media and Petrifilm, and identify a suspicious colony using biochemical identification. Twenty gram of lettuce, twenty gram of cabbage and ten gram of sprout were prepared, and a 5-strain mixture of pathogenic E. coli (Enterohemorrhagic E. coli NCCP11142, Enterotoxigenic E. coli NCCP14037, Enteropathogenic E. coli NCCP14038, Enteroaggregative E. coli NCCP14039, Enteropathogenic E. coli NCCP15661) was inoculated to obtain 1, 2 and 3 log CFU/g. Eighty to ninety milliliter of buffered peptone water (BPW) was placed and pummeled for 60 s. As a results, the Petrifilm method was all positive, but enrichment method of qualitative analysis was negative except for 3-log CFU/g inoculated lettuce. Regarding biochemical identification of pathogenic E. coli, the identification rates were dependent on type of methods and vegetables; lettuce: API 20E 100% (44/44), Microgen GNA 100% (44/44) and Food System 66.7% (10/15), cabbage: API 20E 64.7% (22/34), Microgen GNA 50% (16/32) and Food System 60% (9/15), sprout: API 20E 65.1% (28/43), Microgen GNA 62.3% (27/43) and Food System 53.3% (8/15). These results could be useful in determining an appropriate method to detect pathogenic E. coli in fresh vegetables.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.918-925
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• 2015

An investigation was conducted to evaluate the hygienic status of 33 high school foodservice systems in Yongin city by using hygiene management guide checklist, ATP bioluminescence assay and microbe inspection petrifilm (APC, coliform group, Staphylococcus aureus) of food utensils during use. The 22 hygiene management guide checklist items about facilities, personal hygiene, food control, distribution, washing and disinfection had good grade but there were some inadequate behaviors on observation. The inspection results showed their sanitary condition met the level B of the recommendation of Korea method, it means sanitary management system get settled but more practical CCP system was needed. ATP bioluminescence assay was conducted on surface of food facilities, ATP ranged 425~2,552 RLU on gloves, 541~70,251 RLU on apron, 1,596~88,490 RLU on working desk, 1,177~263,813 RLU on sterilizer grip, 715~32,814 RLU on sterilizer shelf, 114~619,725 RLU on refrigerator grip, 677~319,007 RLU on refrigerator shelf, 71~196,725 RLU on freezer grip, 1,535~233,375 RLU on freezer shelf. APC ranged $66.7{\pm}29.0CFU$ on freezer grip, $102.1{\pm}35.9CFU$ on refrigerator grip, $45.4{\pm}28.2CFU$ on heating cabinet grip, $58.8{\pm}40.4CFU$ on sterilizer grip, the number of coliform group ranged $5.6{\pm}4.9CFU$ on freezer grip, $9.1{\pm}8.7CFU$ on refrigerator grip, $1.2{\pm}1.1CFU$ on heating cabinet grip, $4.5{\pm}4.4CFU$ on sterilizer grip. S. aureus ranged $8.0{\pm}5.6CFU$ on freezer grip, $12.2{\pm}9.6CFU$ on refrigerator grip, $2.1{\pm}1.6CFU$ on heating cabinet grip, $11.6{\pm}6.4CFU$ on sterilizer grip.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.301-307
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• 2018

In this study, a relatively effective process is used to sterilize Escherichia coli on the surface of micro-sized calcium citrate powder using nitrogen and argon as process gases in a low-temperature vacuum plasma treatment. The purpose of this study is to confirm and to introduce the effectiveness of homogeneous surface treatment for the sterilization of fine inorganic powder by the rotatable low-temperature RF plasma system designed by ourselves. The results of the test using 3M petrifilm showed that there were no remarkable spots in the case of the surface of plasma treated powder, whereas the untreated powder showed many blue spots, which indicating that the E. coli was alive. After 5 days, in the same samples, the blue spots were seen to be larger and darker than before, while the plasma-treated powder showed no changes. The results from FE-SEM analysis showed that the E. coli was damaged and/or destroyed by reactive species generated in the plasma space, resulting in the E. coli being sterilized. Furthermore, the sterilization effects according to the selected parameters ($N_2$ and Ar; flow rate 30 and 50 sccm) adapted in this study were mutually similar, regardless of such different process parameters, and this indicates that homogeneous treatment of powder surfaces could be more effective than conventional methods. Therefore, the plasma apparatus used in this study may be a practical method to use in a powerful sterilization process in powder-type food.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.11
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• pp.1719-1723
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• 2010

The purpose of this study was to verify feasibility of using a ATP Luminometer, real-time hygiene monitoring tool for food contact surfaces in foodservices. For this, 54 cutting boards, 70 knives, 21 rubber gloves in 4 institutional foodservices were studied. ATP (RLU: relatively light unit) values by ATP Luminometer were compared with APC (CFU: colony forming unit) of swabbing culture method using aerobic count plates of 3M petrifilm. ATP ranged from 0 RLU/$cm^2$ to 64693 RLU/$cm^2$ on knives, from 0.1 RLU/$cm^2$ to 6743.6 RLU/$cm^2$ on cutting boards and from 31 RLU/$cm^2$ to 465635 RLU/$cm^2$ on the rubber gloves. APC ranged from 0 CFU/$cm^2$ to 166667 CFU/$cm^2$ on knives, from 0 CFU/$cm^2$ to 1000 CFU/$cm^2$ on cutting boards and from 0 CFU/$cm^2$ to 730000 CFU/$cm^2$ on the rubber gloves. To express the degree of association between ATP and APC, a linear regression was performed. There were significant positive correlations found between log RLU and log CFU on the knives (r=0.84, p<0.001), the cutting boards (r=0.79, p<0.001), the rubber gloves (r=0.78, p<0.001). Results of this study showed the possibility that ATP bioluminescence technique can be used as the monitoring tool for surface hygiene in foodservices.

• Food Science of Animal Resources
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• v.23 no.3
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• pp.262-268
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• 2003

Kefir is a traditional fermented milk in Caucasusian area and is made mainly of milk fermented with lactic acid bacteria and yeasts. Six typical kefir grains were selected from ten kefir grains collected from different locals in Korea. Kefir grains were gelatinous in texture and had various shapes of villi, grapes, leaves, hulled millets, and towels. To investigate predominant microflora of kefir grains, SPC, MRS, M17, Rogosa, and APT agar media were used for viable cell count MRS, SPC, and Rogosa media were most acceptable for bacterial cell counts of the selected kefir grains. From one or two of the SPC agar plates which contained around 25∼50 colonies, all grown colonies were isolated and identified. Most predominant bacteria was identified as Lactobacillus fermentum by API 50 CHL kit. The proportions of Lb. fermentum and Lb. brevis among the total identified bacteria were around 41~88% and M4%, respectively. To select the best preservation method for kefir grains, refrigeration, freezing, and freeze drying were compared. Freeze drying was found most suitable for the preservation of kefir grains, based upon their acid-producing activities and production of off-flavors.