• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.179-191
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• 2007

The purpose of this study was to monitor and compare the contamination levels of heterotrophic bacteria and pathogenic bacteria (total coliforms, Escherichia coli O157:H7, Salmonella spp., Vibrio parachaemolyticus, Staphylococcus aureus and Bacillus cereus). The samples collected at fish farms located in the Jeju-island were investigated from March to August in 2006. The contamination levels of S. aureus, B. cereus and Salmonella spp. ranged $0-3.3{\times}10^2 CFU/ml,\;0-2.2{\times}10^2 CFU/ml\;and\;0-5.1{\times}10^1CFU/ml$, respectively, and 85% of moist pellet feeds were contaminated with S. aureus, B. cereus and total coliforms. But total coliforms and E. coli O157:H7 were not detected in oliver flounder (Paralichthys olivaceus). For the production of safe oliver flounder (Paralichthys olivaceus), education of sanitation for employees, control of fish feed, and continuous monitoring for microorganism will be required.

• Food Science and Preservation
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• v.16 no.2
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• pp.139-146
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• 2009

Whole and stem-off cherry tomatoes were packaged using perforated films(LF05, LF10, LF20, and LF40). Gas composition(ethylene, $O_2$, and $CO_2$), firmness(compression and penetration force), color, brix degree, acidity, and total microbial counts were assessed during storage at $10^{\circ}C$ and 85% relative humidity. Gas composition varied with film gas permeability, indicating that modified atmospheric(MA) conditions were achieved. Firmness fell during storage; samples packed using LF05 showed the lowest firmness, corresponding to low gas transmission conditions. L(lightness) and a(redness) values respectively decreased and rose slightly with increasing storage time, but the b(yellowness) values fell notably. Film permeability significantly affected acidity and soluble solid levels. When LF40 packaging was used, acidity and brix scale changes were similar to those seen after PET container packaging. Total microbial counts increased with time after packaging in most films, and pretreatment differences were not significant. Microflora varied between stem on/off tomatoes. Skin wrinkling and juice appearance were common in tomatoes stored in PET containers and LF films of low gas permeabilities(LF05, LF10, and LF20). White molds were partially found on stem-on tomatoes stored using packaging systems. When film packagings were compared, LF40 was optimal, permitting minimal pretreatment yet offering maximal sanitation.

• Journal of Korean Academy of Dental Administration
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• v.6 no.1
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• pp.19-27
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• 2018

The purpose of this study was to determine the level of toothbrush bacterial growth, whether the dryness of the toothbrush head differs depending on the number of holes in the head, and to use these results as a reference for future toothbrush design. Two-millimeter holes were created on the head of the toothbrushes in groups of three, one, or zero holes. We made the solution with Streptococcus mutans, and the toothbrushes were placed in the solution and agitated. The toothbrushes were shaken to remove moisture and allowed to air-dry. The toothbrush heads were swabbed with saline and then placed in two inoculation groups. The first group was inoculated with a 102 dilution of the S. mutans culture and the second was inoculated with the original culture. After incubation, bacterial colony numbers were measured. The number of holes on the toothbrush head correlated with a decrease in number of cultured bacterial colonies. Our model of a toothbrush head with holes indicated that these holes in the toothbrush head were effective in reducing the level of microbial contamination and that a greater number of holes creates an improved toothbrush sanitation effect. The average number of colonies on the head of toothbrush by number of holes was high, followed by the number of holes 0, 1 and 3, and the average number of colony among toothbrush heads was same. The use of a toothbrush with holes between the toothbrush head indicates that it is effective in reducing the level of microbial contamination between the toothbrush head and toothbrush and the higher the number of holes, the better the effect.

• Food Science and Preservation
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• v.18 no.5
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• pp.786-794
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• 2011

To investigate the sanitary-quality level of commercial kimchi in South Korea, the pH, acidity, and microbial-flora changes in the kimchi were determined. Samples of kimchi produced by three different manufacturers (a small grocery store, a small/medium-sized enterprise, and a large food company) were collected. Freshly made kimchi was purchased and fermented at $10^{\circ}C$ for 10 days. The pH of the commercial kimchi on the purchased day was approximately pH 5.8, and that on the $10^{th}$ day of fermentation was ${\simeq}pH$ 4.1. The kimchi purchased from a large company showed a more rapid decline in pH level during fermentation. The saltiness of the kimchi purchased from a medium-sized company was slightly higher than those of the other commercial kimchi samples. The saccharinity index of the kimchi produced by a small grocery store was higher than those of the other samples, and its value deviation was also higher than those of the other commercial kimchi samples. A higher total viable-cell count and a higher lactic-acid bacteria (LAB) count were detected in the kimchi from the large food company at the beginning of fermentation compared to the samples of the two other kimchi manufacturers. The highest cell numbers of gram-positive bacteria (except LAB) and coliform bacteria were detected from the small-grocery-store kimchi, but the coliform bacteria count gradually decreased during fermentation although such bacteria were still detected until the $10^{th}$ day of fermentation. In contrast, coliform bacteria were not detected in the samples from the medium-sized and large food companies. Yeast, which is detected in over-ripened kimchi, was detected in the unfermented kimchi from the small grocery store, which had a below-0.36% acidity level. The gram-positive bacteria (except LAB) that were detected in all the tested commercial kimchi samples were determined to be Bacillus spp., and the gram-negative bacteria were determined to be Escherichia coli, Enterobacter spp., Sphingomonase spp., and Strenophomonas spp. The proportions of all the aforementioned bacteria in the kimchi samples, however, were different depending on the samples that were taken. These results indicate that a more sanitary kimchi production process and a more systematic kimchi production manual should be developed to industrialize and globalize kimchi.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.561-569
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• 2012

To evaluate the bacteriological water quality in Yongnam-Gwangdo, located in western Jinhae Bay, seawater samples were analyzed using sanitary indicator bacteria at 57 sampling stations. According to survey results from January 2007 to December 2009, the range of the geometric mean and the estimated 90th percentile for coliforms and fecal coliforms in the samples were <1.8-16.5 and 1.8-246.8 MPN/100 mL and <1.8-7.1 and 1.8-74.8 MPN/100 mL, respectively. The samples, including those taken from stations located in Wonmunman, Gwangdo, and Dangdong, showed high levels of microbial contamination caused by the climate and weather patterns in the marine environment. The bacteriological water quality in the area met Korean criteria for a designated shellfish growing area for export and National Shellfish Sanitation Program criteria for an approved shellfish growing area, except at station #49. A total of 24 direct pollution sources were discharged into the shellfish growing area. The radius of impact was calculated for each pollution source to assess the effect on the shellfish growing area. The calculated radius of impact for most of the pollution sources was below 300 m. However, the radius of impact for the combined pollution sources in Kyeonnaeryang was 93-1973 m. There were significant differences between the calculated closed sea area and actual monitoring results. The closed sea area values calculated from the fecal coliform load in drainage water tended to be higher than the actual monitoring results. Tidal currents and environmental factors such as salinity, water temperature, sunlight, and microbiological factors affect the survival of fecal indicator bacteria in seawater.

• Journal of the Korean Society of Food Culture
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• v.17 no.3
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• pp.315-328
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• 2002

The purpose of this study was to analyze the problems arising from the actual conditions of the Foodbank, and to implement the HACCP system as a solution in terms of increasing the safety of donated food within the Foodbank. In order to apply HACCP system, the entire Foodbank working process such as preparation, collection, transportation, division, and distribution was considered and analyzed to decide the application point for CCPs. Donated foods mainly consisted of processed foods, raw materials, lunch boxes, and cooked foods from mass catering establishments, which dominated over the others in terms of quantity. Cooked foods were divided into three groups based on menu-types and processing methods. Temperature, pH, and aw were measured on cooked foods, and Total Plate Count, Coliforms, E. coli, Salmonella spp., Staphylococcus aureus, Listeria monocytogenes, and E. coli O157:H7 were conducted in order to apply a HACCP plan. From these experiments, temperature, pH, and $a_w$ of donated food were likely contributed to microbial growth. Donated foods before HACCP implementation showed high numbers in terms of total plate count and Coliforms, both well over the acceptable standard levels. By setting the CCPs on maintenance of donated food below $10^{\circ}C$ and using a $75^{\circ}C$ reheating method, microbiological hazard levels were able to be controlled and lowered. From these results, it is concluded that in order to guarantee food safety, foods donated to the Foodbank must not only maintain a reasonable level of initial microbiological growth, but also must be handled properly through time and temperature controls within the Foodbank system. Furthermore, in terms of implementing the HACCP plan within the Foodbank management structure, basic food safety and sanitation measures, such as reheating facilities and various cold chain systems such as refrigerated vehicle for food transportation are importantly needed. The training and education of Foodbank personnel and management in areas such as awareness of hygiene and safe food handling and practice are also required and necessary.

• Food Science and Preservation
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• v.24 no.5
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• pp.593-599
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• 2017

The objective of this study was to investigate the effect of superheated steam (SHS) and high hydrostatic pressure (HHP) techniques on the improvement of the quality of Bulgogi product during manufacturing process. Bulgogi product was treated with four different cooking/treatment process: conventional cooking (CC), SHS cooking (SHS), CC and then HHP cooking (CC-HHP), and SHS and HHP cooking (SHS-HHP) samples. SHS treated product increased moisture content, and decreased crude protein. Additionally, hardness, gumminess and shear force values were significantly different among the samples (p<0.05). In safety experiment after 14 days of storage at refrigeration temperature indicated that the bacterial population was lower in the case of SHS-HHP as compared to CC-HHP. Changes in texture during the storage periods at $10^{\circ}C$ for SHS-HHP was lowest values with compared to the initial, while shear force values for both tended to decrease with increasing storage period. The TBA and VBN values for SHS-HHP increased to 0.48 ($5^{\circ}C$)-1.68 ($10^{\circ}C$) mg MD/kg and 25.14 ($5^{\circ}C$)-45.14 ($10^{\circ}C$) mg%, respectively after 15 days of storage. Overall, it was found that the combination of SHS and HHP reduced microbial growth, thus leading to improved product quality and sanitation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.2
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• pp.269-276
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• 2016

This study was conducted to determine the inactivation effects of slightly acidic electrolyzed water (SAEW) on microorganisms attached to salted Chinese cabbage and food materials of kimchi, such as slice radish and green onion. In addition, changes in microbial and physicochemical quality of manufactured kimchi during storage at $4^{\circ}C$ for 4 weeks were investigated. Compared to the untreated control with tap water, total bacterial counts (TBC) of Chinese cabbage, slice radish, and green onion were reduced by 1.75, 1.68, and 1.03 log CFU/g at dipping times of 20 min, 5 min, and 10 min, respectively, upon treatment with 30 ppm SAEW at $40^{\circ}C$. Effect of microbial inhibition was higher in salted Chinese cabbage brined in 10% salt (w/v) of 30 pm SAEW at $40^{\circ}C$ than in untreated control with tap water, as indicated by 1.00 log CFU/g reduction. TBC of kimchi manufactured with materials treated with 30 ppm SAEW at $40^{\circ}C$ was not significantly affected compared to untreated control, although coliforms were remarkably reduced compared to the untreated control. At the beginning of storage (1 weeks), TBC and lactic acid bacteria (LAB) counts increased by approximately 9 and 7.66~8.18 log CFU/g, respectively, and coliforms were completely eliminated. The pH and acidity of kimchi at 2 weeks were 4.34~4.49 and 0.55~0.66%, respectively, and then slowly decreased. The texture (firmness) of kimchi decreased with storage time, but the difference was not significant. This combined treatment might be considered as a potentially beneficial sanitizing method for improving the quality and safety of kimchi.

• Food Science and Preservation
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• v.20 no.3
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• pp.424-428
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• 2013

Microbiological contamination of 4 vegetables (garlic, red pepper, perilla leaf and lettuce) collected from 10 restaurants around university was examined. The vegetables were evaluated for total plate count, coliforms, psychrophiles, yeast, and Staphylococcus aureus. The results of total plate count showed the highest value as $5.4{\pm}0.69$ log CFU/g in lettuce, following by $4.8{\pm}1.53$ log CFU/g in red pepper, $4.5{\pm}1.65$ log CFU/g in perilla leaf and $3.4{\pm}1.27$ log CFU/g in garlic. The contamination level of coliforms and psychrophiles were highest in red pepper with maximum as 4.7 log CFU/g and 8.2 log CFU/g, respectively. Red pepper of psychrophiles showed the highest average value as $5.0{\pm}1.82$ log CFU/g followed by $4.2{\pm}1.91$ log CFU/g in lettuce, $4.7{\pm}1.55$ log CFU/g in perilla leaf and $2.4{\pm}2.10$ log CFU/g in garlic. The average number of yeasts were highest in perilla leaf with $4.4{\pm}1.41$ log CFU/g and were lowest in garlic with $0.9{\pm}1.41$ log CFU/g. The contamination level of S. aureus was detected in 27 samples among the total 40 samples with the range of 0.5-5.2 log CFU/g. In conclusion, the microbial quality of the fresh vegetables evaluated in this study was not very good. Therefore, it needs to be enhanced through the good sanitation management and production and distribution methods to improve the safety of fresh vegetables.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.464-477
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• 2013

There is a great need to develop a training program proven to change behavior and improve knowledge. The purpose of this study was to evaluate employee hygiene knowledge, hygiene practice, and cleanliness, before and after HACCP system implementation at one small-size restaurant. The efficiency of the system was analyzed using time-temperature control after implementation of u-HACCP$^{(R)}$. The employee hygiene knowledge and practices showed a significant improvement (p<0.05) after HACCP system implementation. In non-heating processes, such as seasoned lettuce, controlling the sanitation of the cooking facility and the chlorination of raw ingredients were identified as the significant CCP. Sanitizing was an important CCP because total bacteria were reduced 2~4 log CFU/g after implementation of HACCP. In bean sprouts, microbial levels decreased from 4.20 logCFU/g to 3.26 logCFU/g. There were significant correlations between hygiene knowledge, practice, and microbiological contamination. First, personnel hygiene had a significant correlation with 'total food hygiene knowledge' scores (p<0.05). Second, total food hygiene practice scores had a significant correlation (p<0.05) with improved microbiological qualities of lettuce salad. Third, concerning the assessment of microbiological quality after 1 month, there were significant (p<0.05) improvements in times of heating, and the washing and division process. On the other hand, after 2 months, microbiological was maintained, although only two categories (division process and kitchen floor) were improved. This study also investigated time-temperature control by using ubiquitous sensor networks (USN) consisting of an ubi reader (CCP thermometer), an ubi manager (tablet PC), and application software (HACCP monitoring system). The result of the temperature control before and after USN showed better thermal management (accuracy, efficiency, consistency of time control). Based on the results, strict time-temperature control could be an effective method to prevent foodborne illness.