The transmission of the world Installed in an Office occurs through the air. Preventing that transmission, especially in indoor environments like those in airplanes, schools and offices, is a major public health concern. in this study the real situation of lab which is consist of dilution, Ultraviolet-C based air sterilization system. This model include indoor microbe transport which is generated human source. a computer simulation was performed to determine if such simulation can be used effectively to predict the more accurate, but difficult to perform, actual physical experiment. Result show that CFD can be modeled microbe transport effectively and it can be visualized microbe transport separation from flow streamline. also it make a good prediction of microbe transport.

In this study the real situation of apartment house in seoul is reproduced with multi-zone modeling program contam2.4. This model include immune building system(disinfection system) which is consist of dilution, Filter Technology and UVGI(ultra violet germicidal irrdiation). In this study experiments design method used for estimating interaction of HRV air change rate, UVGI air change rate and UVGI grade. Result show that HRV air change rate and UVGI air change rate is most influence factor for remove rate. also Interaction of HRV air change rate and UVGI air change rate is ost influence factor for remove rate.

This study was conducted to evaluate microbial contamination levels of Korea traditional rice cakes such as Sirutteok, Garaetteok and Gyeongdan in the manufacturing process and environment. The microbial contamination levels such as total aerobic bacteria, fungi, coliforms, Escherichia coli, Staphylococcus aureus, Bacillus cereus and Clostridium perfringens of rice cake products were analyzed. The contamination levels of total aerobic bacteria, coliforms, fungi and B. cereus in raw materials were in the range of 2.4~4.5, ND~1.9, 1.2~2.1 and 1.0~2.1 log CFU/g, respectively. The microbial contamination levels of total aerobic bacteria, coliforms, fungi and B. cereus in manufacturing process of rice cakes were increased in the soaking and grinding steps and were decreased in steaming step. E. coli, S. aureus and C. perfringens were not detected in any manufacturing process and environment. The microbial contamination levels of raw materials and final products of rice cake were suitable for microbial safety standard in Korea. However, the manufacturing environment such as equipments and employee's sanitation were in trouble for microbial safety. The results of this study suggest that safety education for personal hygiene and safety management in processing environment are continuously required to assure safety in working environment and employee's individual hygiene.

This study was conducted to assess the levels of microbiological hazards of preprocessed Namuls, which were served at the school foodservice. 19 preprocessed ground or root vegetables were collected from 21 schools in May to June of 2011. Heavy contamination of aerobic plate counts (from 3.39 to 8.42 logCFU/g) and total coliform groups (from 3.16 to 7.84 logCFU/g), enterobacteriaceaes (from 2.53 to 7.55 logCFU/g) were detected in preprocessed Namuls. In addition, the detection rates of Escherichia coli, Staphylococcus aureus and Bacillus cereus (emetic form) were 4.3%, 11.7% and 2.1%, respectively. In addition, sanitary indicative bacterium at preprocessing steps of root vegetables (lotus root, burdock root, bellflower root) and blanched Namuls (bracken, sweet potato vine, chinamul) were analyzed. Aerobic plate counts, coliform groups, and enterobacteriaceaes were not effectively removed during preprocessing including washing and soaking steps. In the case of blanched Namuls (bracken, sweet potato vine, chinamul), contamination levels increased more after drying process and no significant reduction effect on the levels of microbial contamination was observed during preprocessing steps. Thus, effect of preprocessing steps on the microbiological hazards in Namuls must be reevaluated to improve the microbiological quality of preprocessed Namuls at the school foodservice and retail markets.

This study was conducted to evaluate the microbiological hazard on nursery school children's hands and to investigate the reduction effect of hand washing education. A total of 59 nursery school children's hands were tested. The average number of total aerobic bacteria was 3.72 ± 0.38 log CFU/hand. Five children's hands(2 male and 3 female) were positive(14.3%) for the coliform bacteria. These results showed that hand washing education are required repetitively. Among the pathogenic bacteria tested in this study, Staphylococcus aureus and Bacillus cereus were detected in 9(25.7%) and 16(45.7%) out of 35 their hands, respectively. Twelve out of sixteen B. cereus isolates(70.0%) produced enterotoxin. The results indicate that the hand hygiene of nursery school children needs to be improved. Comparing before and after hand washing in educated and non-educated group, the reduction effect of total aerobic bacteria on their hands was 0.42 and 0.60 log CFU/hand, respectively. The educated group showed 0.18 log CFU/hand higher reduction effect than non-educated group but microorganism did not eliminate perfectly. From the results, using a hand sanitizer after washing with soap and the continuous hand washing education are required to control the contaminated bacteria on nursery school children's hands.

Produce, including leafy vegetables, has been implicated in several outbreaks of food illness. To evaluate microbiological safety of lettuce and it’s cultivation area, a total of 147 samples were collected from lettuce farms and post harvest facility at Icheon, Gyeonggi province. The collected samples were assessed for presence of sanitary indicator microorganisms (Aerobic plate count, coliform count, Escherichia coli) and foodborne pathogens (Escherichia coli O157:H7, Salmonella spp., Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus). The population of APC was over 4.0 log CFU from most of the samples. While the numbers of APC, and coliform of lettuce at 62 days after transplanting were 4.18 log CFU/g, and 1.00 log CFU/g, respectively, those of 10 days after transplanting were 5.37 log CFU/g, and 2.87 log CFU/g, respectively. B. cereus was highly detected from soil and balance which were contaminated with 3.5 log CFU/g, and 2.6 log CFU/100 cm2, respectively. The number of E. coli recovered from gloves was 3.5 log CFU/hand. However, E. coli O157:H7, Salmonella spp., and L. monocytogenes were not detected. These data suggested that risk management system should be introduced to lettuce farms to enhance safety of lettuce.

본 연구에서는 고추재배 농가에 대한 농산물우수관리제도(Good agricultural practices, GAP) 적용을 위한 미생물학적 위해분석을 수행하였다. 경북 청송에 위치한 고추재배 농가 3곳을 선정한 후 재배환 경·도구, 작물, 작업자 및 공중낙하균에 대하여 시료를 수집하였고, 위생지표세균, 병원성 미생물 및 곰팡이를 분석하였다. 그 결과, 일반세균, 대장균군 및 곰팡이는 3 곳의 농가에서 각각 0.7~6.2, 0.2~4.7, 0.4~4.3 log CFU 수준으로 확인되었고 총 90점의 시료 중 4점의 시료(작물 잎 1점, 농업용 수 1점 및 토양 2점)에서 대장균이 검출되었다. 병원성 미생물 Staphylococcus aureus의 경우 B 농가의 작업복에서만 1.0 log CFU/100 cm2로 검출되었고, Bacillus cereus는 B와 C 농가의 재배환경·도구와 작업자에서 1.0~2.5 log CFU 수준으로 확인되었다. 그러나 다른 병원성 미생물의 경우는 모든 시료에 서 검출한계이하의 수준으로 검출되었다. 이상의 결과로 볼 때 농가에서 재배되고 있는 고추에 대한 잠 재적인 미생물학적 위해가 확인되었고, 이를 최소화할 수 있는 관리시스템, 예를 들면 GAP와 같은 관리 시스템이 미생물학적 위해로부터 고추의 안전성 확보를 위해 적용되어야 할 것으로 판단된다.

Rice has been the most important staple food in everyday meals of Korean people for thousands of years. Nowadays, it is getting increasingly used as flour ingredients in a variety of processed foods, so that it is consumed in more diversified ways. As a consequence, production volume of rice flour to manufacture rice cakes, noodles,breads, or confectioneries is recently getting increased in Korea. But there are not sufficient research outcomes to guarantee Korean consumers microbiological qualities of rice flour as well as rice. As a preliminary experiment,therefore, the microbiological profiles (aerobic mesophilic bacteria (AMB), spore-forming aerobic bacteria (SAB),lactic acid bacteria (LAB), yeasts and molds (YM), and Escherichia coli and coliforms) have been monitored for nine retailed white rice samples in this study. AMB counts ranged 10² - 10^6CFU/g for all the nine white rice samples. All the nine rice samples have SAB counts within a narrow range (1.0 × 10²- 2.5 × 10³CFU/g). LAB was detected in two white rice samples (4.0 × 10² and 3.7 × 10³ CFU/g). YM was detected in one white rice sample (2.0 × 10² CFU/g)only. E. coli was not detected from all the nine samples. Coliforms were detected in one white rice sample (4.1 × 10CFU/g) only. All the rice samples were conclusively considered to have various microorganisms, though most of them are harmless and some, such as coliforms, may be harmful.

This study was conducted to develop an appropriated management for safety of children snacks sold around school. Total 598 items as targeted food were collected; 66 biscuits, 320 candies, 57 chocolates, 40 ice creams and 115 beverages. Microbiological hazards such as total aerobic bacteria, Coliforms, Escherichia coli, Bacillus ceruse, Yeasts & molds were measured by analytical method in Korean food code. Total aerobic bacteria and Yeasts & molds were detected in cookies at the level of less than 2.69 and 2.65 log10CFU/g and the detection rates were 54.55 and 62.12%, respectively. Bacillus cereus was detected in 1 snack only at the level of 1.39 log10CFU/g but it was less than Korean microbial standards and specifications (3 log10 CFU/g). Total aerobic bacteria and Yeasts &molds were detected in candies less than 2.86, 3.36 log10CFU/g and the detection rates were 46, 8% respectively. Total aerobic bacteria, Yeast & mold were detected in chocolates at the levels less than 2.52 and 1.87 log10CFU/g and the detection rates were 33 and 22% respectively. Total aerobic bacteria in both ice creams and beverages were detected at the levels less than 3.39 and 1.35 log10CFU/g and the detection rates were 82 and 5% respectively. Coliforms were found in one ice cream (1.39 log10CFU/g) only. The result of this study indicated that all children snacks around school were suitable for microbial standard and specifications in Korean Food Code. However, since most children snacks around school are circulated without proper storage temperature and handing condition, consistent microbial management for children snacks are needed.

This study was carried out to evaluate the microbiological characteristics of retail chicken meats stored under various conditions. Nine of whole chickens and nine of chicken breasts were used for bacterial analysis. Each chicken meat was divided into subsamples of 25 g each followed by storage at room temperature (25℃), refrigeration temperature (4 ℃), and freezing temperature (—20℃) for 180 min, 5 days, and 3 days, respectively. The standard plate counts were performed for the enumeration of the total aerobic bacteria. The number of aerobic bacteria was gradually increased by 1 log in samples held at the room temperature for 180 min. There was statistical difference in the number of bacteria between at 0 min and at 180 min of storage. For samples stored at 4℃ for 5 days, the number of bacteria was increased from 5.11 to 7.26 log CFU/g in chicken breast and 3.83 to 6.04 log CFU/g in whole chicken with statistical difference. No significant changes were observed in frozen chicken. The results of this study may provide useful information to consumers for proper storage and safe handling of chicken meats.

In recent years, the national surveillance network reported the isolation of Enterobacter sakazakii and coliform from powdered infant formula (PIF). PIF means a breast-milk substitute specially manufactured to satisfy the nutritional requirements of infants during the first month. PIF is not sterile infant food and may be intrinsically contaminated with pathogens, such as E. sakazakii and Salmonella enterica that can cause serious illness in infants. Intrinsic contamination of PIF with E. sakazakii and S. enterica has been a cause of infection and illness in infants. E. sakazakii is an opportunistic pathogens and more commonly found than S. enterica in manufacturing environment. Even low levels of contamination of E. sakazakii and S. enterica in PIF were considered to be a risk factor. Enterobacteriaceae showed the high prevalence and some Enterobacteriaceae causing disease were detected. The infant food industry should be encouraged to reduce the concentration and prevalence of E. sakazakii in both the manufacturing environment and PIF. The presence of these microorganisms in PIF may occur as a results of contamination through ingredients during PIF manufacturing process and from the processing environment during packaging. In order to ensure that ingredients and packaging materials are microbiologically suitable, PIF manufacturer need to be selection of supplier according to stringent criteria (e.g. HACCP, good hygienic practices) and testing of ingredients especially colostrum. In conclusion, it is continually necessary to monitor the potential pathogens and reduce them to improve the microbial quality of non-sterilized PIF.

The purpose of this study was to investigate the microbiological characteristics and antioxidant activity of tomato sauce in terms of the variety of herbs that have been widely used in Western cuisine. As storage time increases, the number of total microbes changes, but the bacteria count was in the range of 1.0×101-2.1×102, which did not increase much over 60 days of storage. The reason seems to be that the amount of heat treatment undergone by this type of sauce type, and its acidity make for difficult conditions for microbes to live. Yeast and mold measurements showed that yeast and mold were not detected for up to 30 days of storage in the tomato sauce with various types and amounts of added herbs. After 45 and 60 days, the yeast and mold count was in the range of 1.0×101-8.5×101, and the same in the control. Measurements of phenolic compounds in 60 days of storage showed that tomato sauce with different types and amounts of added herbs had the lowest amounts relative to the control for all storage periods. The more herbs that were added, the higher the phenolic compounds resulted. As storage times increase, the phenolic compounds showed a tendency to decline. The DPPH radical scavenging effects of the tomato sauce herbs added showed a tendency to increase antioxidant activity when more herbs were added. The microbiology results of the storage test of tomato sauce with added herbs showed that the amount of microorganisms in tomato sauce with added herbs did not increase much in 60 days of storage at 4oC. The amount of microorganisms was small, so tomato sauce with added herbs can be used for 2 months with refrigeration.

The objectives of this study were to investigate the microbial contamination levels on food service in university and to provide the information of microbial contamination to improve food safety. A total of 288 samples were collected during summer and winter season between 2006 and 2008 from 4 food services located in the university in Western Gyeongnam and were used to detect sanitary indicator bacteria [aerobic plate count (APC), coliform,and Escherichia coli] and pathogenic bacteria (Staphylococcus aureus, Salmonella spp.). As a result, APC and coliform for hand and kitchen utensils which are used often by the employee were detected at high levels of 1.1~5.5and 1.3~5.3 log CFU/(100 cm2, hand), respectively. The contamination levels of APC and coliform in cooked foods and drinking water were 0.8~6.4 and 1.3~5.0 log CFU/(g, mL), respectively. Especially, the cooked foods showed the highest contamination for APC (2.1~6.4 log CFU/g) and coliform (1.0~5.0 log CFU/g). We think the reason that the cooked foods may be contaminated with APC and coliform on cooking process by using employee’s hand and kitchen utensils. Moreover, S. aureus for hand and kitchen utensils was detected at levels of 2.8~3.0 and 2.0~2.3 log CFU/(g,hand), but Salmonella spp. was not detected. According to the above results, contamination levels of the samples were mostly decreased irrespective of summer and winter season. The results obtained indicated that it is necessary to periodic monitoring for microorganism contamination and education about personal and environmental hygiene to employee for ensuring food safety of food service in university.

The objective of this study was to evaluate the antifungal properties of xanthorrhizol (extract from curcuma xanthorrhiza) against Candida albicans. Some of the commercial products were evaluated for their ability to inhibit growth of C. albicans. OTC product containing povidone iodide and cosmetic grade product with surfactants were tested. Antifungal activity was shown in 1.56% of OTC product, however, there was no antifungal effect in cosmetic product. For the comparison, we tested several materials. Povidone iodide, lemon tea tree oil and xanthorrhizol showed antifungal activities against C albicans in 0.25, 0.062 and 0.007%, respectively. We also tested the antifungal effects of povidone iodide and xanthorrhizol in surfactant base. Test results revealed that 2.5% of povidone iodide and 0.156% of xanthorrhizol showed similar antifungal effects. These findings support the application of xanthorrhizol for vaginal cleanser or personal cares using antifungal effect.

The aim of this study was to determine exposure assessment of pathogenic bacteria in edible ices by using the monitoring data from the previous study. According to the results of exposure assessment of edible ices contaminated with S. aureus, the contamination level of S. aureus in raw materials was higher than other foodborne pathogens, and the contamination level of S. aureus in mixed samples increased much before sterilization. The most significant reduction in contamination level was observed in mixed samples after sterilization, thus, the contamination levels in frozen final products was less than that of raw materials. Overall, the possibility for the infection of foodborne bacteria from the intake of edible ices per person per day was ranged from minimum 5.89 × 10-7 to maximum 5.01 × 10-5. For more realistic estimates, consumption of edible ices and dose-response model must be studied further.

This study was carried out to analyse the microbiological contamination and biogenic amines(BA) content in Korea traditional soybean paste and commercial soybean paste. The results of microbiological anaylsis through Korean traditional soybean pastes(L1~L4) were 7.8 ± 0.1 log CFU/g ~ 7.9 ± 0.1 log CFU/g, commercial soybean pastes(H1~H6) were 6.2 ± 0.1 log CFU/g ~ 7.4 ± 0.1 log CFU/g for APC (Aerobic Plate Count), and L1~L4, H5, H6 soybean pastes were 2.3 ± 0.4 log CFU/g ~ 2.6 ± 0.1 log CFU/g for Bacillus cereus. But other microorganism was not dectected. Among biogenic amines, PUT(putrescine), TYR(tyramine), HIS(histamine), PHE(2-Phenylethylamine) were dectected high level and CAD(cadaverine), TRY(tryptamine), AGM(agmatine) were dectected medium level and SPD(spermidine), SPM(spermine), NOR(noradrenaline), SER(serotonin) were dectected low level. Dectected contents of biogenic amines were higher in commercial soybean paste compared to the traditional soybean paste.

This study was conducted to determine microbiological assessment on edible ices, which is one of mandatory items for HACCP application, and to provide basic scientific data for the improvement of HACCP system. In HACCP applied edible ice companies, the contamination levels of total counts, yeast and mold, and coliform from raw materials, mixed samples before sterilization, mixed samples after sterilization, and final products of edible ices were lower than those of non-HACCP applied edible ice companies. Foodborne pathogens, such as L. monocytogenes, Salmonella spp., B. cereus, S. aureus, Y. enterocoliticawere not detected in all samples of edible ices from HACCP applied edible ice companies, but S. aureus was isolated from 1 raw material, 1 mixed samples before sterilization and 1 final product of edible ices from non-HACCP applied edible ice companies, respectively.

본 연구에서는 대표적인 즉석섭취식품 5종(김밥, 초밥, 회, 샐러드, 샌드위치)에 대한 미생물 모니터링 검사를 실시하여, 이들 제품에 대한 위생 안전성 확보를 위한 기초자료를 제공하기 위해 진행되었다. 이를 위해 전국의 대형 백화점, 할인점, 슈퍼 등지에서 판매되는 즉석섭취식품 5종, 총 440품목을 수거하여 위생지표세균 검사 및 식중독균 검사를 실시하였다. 제품별로는 초밥이 20.4%로 가장 높은 미생물 검출율을 보였으며, 그 다음으로 13.3%의 김밥, 12.5%의 회, 6.9%의 샐러드, 2.8%의 샌드위치의 순서로 나타났다. 검출된 미생물을 살펴 보면 황색포도상구균이 6.6%로 가장 많이 검출되었으며, 다음은 2.7%의 대장균군, 2.3%의 리스테리아균, 0.7%의 바실러스 세레우스균, 0.5%의 대장균 순서로 검출되었으며, 장염비브리오균과 살모넬라균은 검출되지 않았다. 검출된 황색포도상구균의 정량분석 결과는 전체적으로 200~5,500 cfu/g 의 분포를 보였으며, 평균적으로는 600 cfu/g을 나타내었다.

Anti-microbiological effects of xanthorrhizol, ie., extract from curcuma xanthorrhiza and extract from houttuynia cordata Thunb. against influenza virus and E. coli O157 were tested. From the influenza experiments, the effects were shown above 93 % in case of houttuynia cordata Thunb. extract, however, the effects was not shown in case of xanthorrhizol. The effects were sustained in mixtures of houttuynia cordata Thunb. and curcuma xanthorrhiza extracts. We also tested the anti-microbiological effects of hand sanitizer containing houttuynia cordata Thunb. and xanthorrhizol. The effect of hand sanitizer containing 2,000 ppm of xanthorrhizol and 500 ppm of houttuynia cordata Thunb. extract was better than that of commercialized foreign product.

The purpose of this study was to investigate the antibacterial effect of films on shelf-life and microbiological Safety of pork meat. Effects of antimicrobial films against total aerobic bacteria, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella Typhimurium, Staphylococcus aureus in pork meat were evaluated during storage of 14 days at 5℃, 10℃ and 15℃. Antimicrobial films were developed with addition of a natural substance, wasabi extracts (Wasabia japonica). At 5℃ storage, growth of total aerobic bacteria, E. coli O157:H7, L. monocytogenes were inhibited higher than at 10 and 15℃. Especially, the numbers of S. Typhimurium and S. aureus were increased gradually at 5℃ even in the control sample, and it takes more than 14 days to increase in every sample upto 6 log10 cfu/g. The higher antimicrobial effects of the films were observed at storage of 5℃ than at 10oC and 15℃. There was a limit of a single treatment of antimicrobial film to prolong shelf-life of pork meat. The synergistic effect of antimicrobial film were observed with addition of refrigeration at 5℃.