• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.9
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• pp.1265-1270
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• 2009

Pathogens contaminated on the surface of utensils could contribute to the occurrence of outbreaks due to cross-contamination to foods during the food preparation process. Therefore, the efficacy of chemical sanitizers (chlorine-based and alcohol-based commercial sanitizers) and dry-heat ($71^{\circ}C$) on inhibiting biofilms of five foodborne pathogens (Escherichia coli O157:H7, Salmonella Typhimurium, Pseudomonas aeruginosa, Listeria monocytogenes, and Staphylococcus aureus) on the surface of stainless steel and polypropylene were investigated in this study. Initial populations of pathogens were 8.8$\sim$9.3 and 9.4$\sim$10.3 log CFU/coupon on the surface of stainless steel and polypropylene coupon, respectively, and these populations were not significantly reduced when they were treated with water for 5 min at room temperature. Treatments with chlorine sanitizer and dry-heat were not effective on inactivating pathogens on the surfaces of stainless steel and polypropylene. In contrast, treatments with alcohol sanitizer were very effective on inactivating pathogens on the surfaced of stainless steel and polypropylene. Reduction levels ranged from 3.4 to 6.4 log and from 5.5 to 7.4 log CFU/coupon in stainless steel and plastic coupons, respectively. From these results, alcohol-based sanitizer could be used as a potential way for controlling microbial contamination on the surface of utensils, cooking equipment, and other related environments.

• Journal of Food Hygiene and Safety
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• v.29 no.1
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• pp.6-15
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• 2014

This study was performed to acquire the information on the foodborne pathogen risk management programs in a couple of developed countries by the expert meeting and searching the information on the web. The backgrounds, strategies and effects related to microbial hazards of the foodborne pathogen reduction programs in fresh produce (US), Escherichia coli O157:H7 in ground beef (US), Salmonella in chicken, pork and eggs (Denmark), and Vibrio parahaemolyticus in seafood (Japan) were investigated for case study. A comparison among the pathogen reduction programs was conducted to find advantages and disadvantages and implications of the policies to bring out implications of the programs. A model for foodborne pathogen reduction program was developed based on both the CODEX risk management scheme and the case studies as follows; 1) preliminary risk management activities, 2) planing a foodborne pathogen reduction program, 3) option identification and selection, 4) implementation (conducting the each stake-holders role and applying the intervention methods), 5) monitoring activities, 6) interim review, 7) continuation or amendment of implementation method by the interim review before achieving the goal, and 8) final review and additional cost-benefit analysis if necessary. This proposed model according to the role of the stake-holders can be used to conduct microbial risk management programs in Korea in the near future.

• Journal of Korean Biological Nursing Science
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• v.9 no.1
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• pp.33-48
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• 2007

목적 : 본 연구에서는 한국인 소아의 침 및 성인의 질부로부터 분리한 1367개의 유산 생성 균주 중 4가지의 장내 병원성 세균;Methicillin-resistant Staphylococcus aureus(MRSA), Listeria monocytogenes, Salmonella typhimurium, Escherichia coli O157에 대해 발육억제 효과를 나타내는 유산 균주를 분리하고 분리된 균주의 Probiotic으로서의 가능성을 조사하고자 하였다. 방법 : 네 가지 병원성 세균을 대상으로 agar spot test와 Catalse test를 시행하여 1367개 균주 중 최종적인 실험대상 균주를 선정하였다. 최종 선정된 유산균과 네 가지 병원성 세균을 혼합 배양하여 병원성 세균증식 억제 효과를 보았다. 또한 최종균주의 probiotic으로서의 가능성을 확인하기 위해 균을 동정하고 내산성 등 몇 가지 특성을 관찰하였다. 결과 : Agar spot test 결과 전체의 15.7%에 해당하는 215 균주가 MRSA에 대해 억제 효과를 나타내었으며 215 균주 중 9.8%에 해당하는 21 균주가 L. monocytogenes에도 동시에 억제효과를 나타냈다. 이들 균주 중 가장 탁월한 효과를 보인 Lb 1250을 실험 대상 균주로 선정하였다. Lb(Lactobacillus) 1250과 상술한 병원성 세균을 각각 혼합 배양하면 Lb 1250 존재 하에서 MRSA의 증식은 $10^4$배 억제되었으며, L. monocytogenes는 $10^3$배의 억제 효과를 보였다. 그러나 S. typhimurium, E. coli O157에 대해서는 아주 미약한 효과를 나타냈다. Lb 1250의 몇 가지 특성을 조사한 결과 Lactobacillus delbrueckii subsp. delbrueckii로 동정되었으며, 이는 $H_{2}O_2$를 잘 생산해 내는 균주이었다. 또한 이 균주는 우유에서 curd를 약하게 생성하며 이 curd의 향은 달콤하고 최종 pH가 4.6까지 감소하였으며, pH 2와 같은 강산의 조건하에서 배양한 결과 2시간 후에도 상당한 생존도를 유지하였다. 결론 : 이상의 결과에서 Lb 1250은 병원성 세균의 성장을 억제함을 관찰하였고, probiotic으로서의 이용가능성을 확인하였다.

• Korean Journal of Food Science and Technology
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• v.52 no.5
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• pp.560-563
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• 2020

Cold plasma has been applied to improve quality of food product; however, studies on its effects on microbial and physicochemical qualities of rice noodles are rarely conducted. In this study, changes in the quality characteristics of rice noodles treated by cold plasma were determined. Cold plasma was generated in a square-shaped plastic container (250 W, 15 kHz, ambient air), and dielectric barrier discharge plasma treatments were applied to rice noodle samples for 0, 10, or 20 min. Rice noodles inoculated with either Bacillus cereus or Escherichia coli O157:H7 were subjected to plasma treatment for 20 min, and the approximate bacterial count reduction were 4.10 and 2.75 log CFU/g, respectively. The Hunter color values of the sample were increased after cold plasma treatment. Peroxide values and thiobarbituric acid reactive substance (TBARS) were increased with an increase in cold plasma treatment time. Futhermore, lipid oxidation was enhanced. Although further studies are warranted to evaluate changes in chemical qualities, such as lipid oxidation of rice noodles, induced by cold plasma, the results suggest that cold plasma can improve the microbial and physical qualities of rice noodles.

• Korean journal of food and cookery science
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• v.19 no.2
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• pp.195-209
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• 2003

The purpose of this study was to identify the hazard analysis critical control point on food production and transportation flow, applied to home-delivered meals for the elderly. To carry out this study, 1) pan-fried oak mushroom and meat, soy sauce glazed hair tail, and roasted dodok were selected as high nutrient and preferred foods for the elderly and 2) time, temperature, and microbiological quality(standard plate count, coliform, Salmonella spp, Vibrio parahaemolyticus, Staphylococcus spp., Escherichia coli O157:H7, and Listeria monocytogenes) were measured at various phases of the home-delivered meal production and its transportation flows. The results of this experiments are as follows: The temperature measured at cooling phases during the home-delivered meal production flows was 19.2 ∼ 20.0$^{\circ}C$ for the pan- fried oak mushroom and meat and the roasted dodok and was 24.0 ∼ 25.2$^{\circ}C$ for the soy sauce glazed hair tail. These temperature were in the potentially dangerous zone. Microbiological analysis showed that S. spp. was higher in the raw ingredients, including oak mushroom, hair tail, radish, and dodok, than the standard limit. SPC was lower than the standard limit from cooking to transportation phase, but SPC increased significantly during the cooling and packaging phase. The level of coliform detected was far lower than the standard limit and was not detected at all during the transportation phase. Few S. spp. was detected in the pan-fried oak mushroom and meat, but was found in above standards limit during the wrap packaging phase in the soy sauce glazed hair tail and roasted dodok. The level decreased rapidly during the holding and transportation phase. Sal. spp., V. parahaemolyticus, S. spp., E. coli O157:H7, and L. monocytogenes were not detected. For the pan-fried oak mushroom and meat, the critical control points were during the purchasing and receiving of raw ingredients, cooling, and packaging phases. For the soy sauce glazed hair tail and roasted dodok, the critical control points were during the purchasing and receiving of raw ingredients, preparation, cooling, and packaging phases.

• Journal of Food Hygiene and Safety
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• v.31 no.6
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• pp.406-413
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• 2016

This study was performed to evaluate and establish a sample preparation method for the detection of food-borne pathogens in animal origin foods. Ham, yogurt, and Korean beef inoculated with Escherichia coli O157:H7, Staphylococcus aureus, and Salmonella Typhimurium, were tested for the effects of diluent composition, processing time, and proportion of diluent to sample. The diluents used were peptone water (PW), Saline solution (SS), Butterfield's phosphate buffered dilution water (BPD), and Buffered peptone water (BPW). The processing time periods considered for the samples were 30, 60, 90, 120, and 300 sec, and the proportions of diluent to samples tested were 1:2, 1:4, 1:9, and 1:19. Yogurt and beef showed the highest number of bacteria when treated with BPW (p < 0.05). However, ham showed no significant difference between the treatments with four different diluents. Optimum proportions of diluent to ham, yogurt, and beef were 1:9, 1:2, and 1:4, respectively. The processing time of 120 sec was chosen as optimum, because it showed the best recovery rate in all sample types. In this manner, detection of food-borne bacteria with the selected optimal conditions was indicated by a recovery rate of more than 85%. These data suggest that an appropriate diluent composition and diluent volume should be used depending on the type of sample, which would thereby increase the accuracy of detecting food-borne bacteria in animal origin foods.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.243-248
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• 2011

The prevalence and distribution of hazardous microorganisms were investigated from the major perilla cultivation area at Milyang, Gyeongnam province, Korea. Aerobic plate count (APC) and coliform count of perilla leaves were 4.82 log CFU/g and 3.85 log CFU/g, respectively. E. coli, S. aureus and B. cereus were detected in 3.0% (4/114), 7.9% (9/114) and 46.5% (53/114) of examined perilla leaves. However, E. coli O157:H7, Salmonella spp, and L. monocytogenes were not detected. The distribution of hazardous microorganisms in perilla leaf cultivation environment were compared and the concentration of APC and coliform counts were more than 3.0 log CFU/(mL, g, $100cm^2$, hand) from most of the samples. S. aureus were detected from irrigation water, packing table, packing vinyl, hand, and clothes. Also, B. cereus was frequently detected from the examined samples. Especially, packing table and collection container were contaminated with maximum 5.5 log $CFU/100cm^2$ of B. cereus. Good Agricultural Practice (GAP) system should be introduced to farms to enhance the safety of perilla leaves.

• Food Science and Preservation
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• v.13 no.2
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• pp.234-240
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• 2006

The purpose of this study was to evaluate microbiologically cooking utensils, equipment employees, and environment in 12 large Korean, Western, Chinese, and Japanese restaurant. Microbiological testing was conducted for pathogens including E. coli, Samolnella, L. monocytogenes, S. aureus, E. coli O157:H7, V. parahaemolyticus, B. cereus, and Y. enterocolitica as well as total plate count and coliforms. The results showed cooking water and drinking water in some Korean restaurants and drinking water in some Western and Japanese restaurants were unsatisfactory, especially, barley tea, which was cooled after being boiled, was unsatisfactory. Most cooking utensils such as knives, cutting boards, kitchen towels, tongs, and basket had total plate and coliforms count in excess of standards, and knives and cutting boards at some Chinese restaurant had E. coli. At some restaurant, S. aureus was found on some food worker's hands. Also, the total plate count of the air showed a high count around worktables, inside the refrigerator, and in the kitchen in most restaurants. These result suggest that sanitation needs improvement in the environments in these foodservice establishment.

• Journal of Life Science
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• v.20 no.7
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• pp.1107-1112
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• 2010

In this study, the stable maintenance of bioactivity in alkaline ionized water (AIW) and antibacterial effects of AIW were evaluated to confirm benefits of AIW. As controls, purified water (PW) and tap drinking water (DW) were used. The pH and ORP (oxidation-reduction potential) of AIW, PW and DW used were 9.5 and 120 mV, 7.2 and 144 mV, and 7.3 and 564 mV, respectively. High level of minerals was observed in DW (DW>AIW>PW of mineral contents). Concentrations of $Ca^{++}$ and $Na^+$ in DW were 14.5, and 8.4 mg/l, respectively, while no $Ca^{++}$, $Mg^{++}$, $K^+$, and $Na^+$ were detected in PW. Evaluation of antioxidant activities for AIW, PW and DW showed that the waters did not act as antioxidants. However, the DPPH (1,1-diphenyl-2-picryl hydrazyl) or superoxide radical scavenging activities or reducing power of vitamin C were stably maintained in AIW and PW, though not in DW, against heat treatment ($60^{\circ}C$) or vigorous shaking (120 rpm) at $37^{\circ}C$. Similarly, after aspirin treatment at $60^{\circ}C$ for 1 hr, the antithrombosis activity in PW and AIW was 62.6% and 55.3%, while that of DW was 52.1%. Furthermore, cell growth analysis and viable cell count of Escherichia coli H7:O157 in PW, AIW and DW showed that AIW and DW, not DW, have antibacterial activities. Our results suggest that the state of water, for example pH, ORP and mineral contents of water, should be considered in medicine or food industries, and that AIW has high potential for utilization in various fields.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.474-478
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• 2005

Because it possesses anti-inflammatory, antifungal, antiviral, and tissue regenerative properties, propolis has been used for thousands of years in folk medicine for multiple purposes. Although the antimicrobial activity of propolis has already been demonstrated, very few studies have been conducted on bacteria of clinical relevance in dentistry. The aim of this study is to evaluate the antimicrobial, anti-inflammatory, and anti-oxidative activities of 0.1% and 1.0% propolis, both of water-extracted (proAQ) and ethanol-extracted (proAL) propolis, for industrial applications. In studies of antimicrobial activity, the growth of Staphylococcus aureus ATCC 35556, Salmonella enteritidis ATCC 12021, Escherichia coli O157:H7, and Candida parapsilosis KCCM 35428, all general food or clinical pathogens, were tested. The culture medium used was trypticase soy broth including 0.6% yeast extract; after 6 hr of incubation, the turbidities were measured at 620 nm with a spectrophotometer. The results indicate that the antimicrobial effects of both 1.0% proAQ and 1.0% proAL were greater against the growth of S. aureus ATCC 35556 and C. parapsilosis KCCM 35428 rather than those of S. enteritidis ATCC 12021 and E. coli O157:H7. Additionally, it appears that the anti-inflammatory effects of proAL are greater than those of proAQ. The anti-inflammatory effects were evaluated by measurement of the inhibition of hyaluronidase activity in vitro. At a 1% concentration, the anti-inflammatory effects of proAL were greater than those of proAQ. Finally, the anti-oxidative effects of 1% and 10% solutions of each extract sample were measured according to the TBA method at $40^{\circ}C$ for 1, 2, 3, and 5 days and were compared with 1.0% BHT. The results indicate that the anti-oxidative effects at 0.1% for both proAQ and proAL were not significantly different than the anti-oxidative effects at 1.0% BHT (p<0.05). Thus, it appeared that the alcohol-extracted propolis had greater antimicrobial, anti-inflammatory, and anti-oxidative effects than the water-extracted propolis. This is based on the presumption that major biofunctional components were fat-soluble, rather than water-soluble.