• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.965-970
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• 2002

This study was conducted to investigate inhibition effect of sanitizers against E. coli and a hygienic condition on the surface of utensils and equipments which were used to food service. Samples swabbed using cotton were collected from the surface of stainless steel, wood and plastic utensils and equipments which were used to food service at four elementary schools in Busan and analyzed by measuring the total, coliform and Salmonella spp. count. Total plate counts were 10$^4$~10$^{5}$ CFU/100 cm$^2$ in most of utensils and equipments except plastic cutting board. There were lots of coliforms in slicer (2.8$\times$10$^1$CFU/100 cm$^2$) and peeler (1.1$\times$10$^1$CFU/100 cm$^2$). It was indicated that the sanitary condition of some utensils and equipments such as slicer and peeler should be improved promptly. To investigate inhibition effect of sanitizers against E. coli, the surface of utensils and equipments used in food service was treated at different concentration of sodium hypochlorite for 1 minute and 3 minutes, respectively. The plastic utensils and equipments were most effective aganist E. coli at 100 ppm sodium hypochlorite for 3 minutes. But the stainless steel and wood were most effective at 200 ppm sodium hypochlorite for 3 minutes. It was also treated with 70% ethyl alcohol for 10 seconds and 30 seconds, respectively. The stainless steel utensils and equipments were most effective aganist E. coli at 10 seconds, but plastic and wood were most effective at 30 seconds. Therefore, the results of this study indicated that standardization of disinfection method of utensils and equipments used in food service should be given and sanitation training for dietition should be conducted continuously.

• Journal of Food Hygiene and Safety
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• v.23 no.4
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• pp.291-296
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• 2008

The study was undertaken to provide information on the efficacy of sanitizers against bacteria with and without organic road dried on to food contact surfaces using the surface test method which EU and USA are currently implementing as one of their official test methods. Escherochia coli ATCC 10536 or Staphylococcus aureus ATCC 6538 was inoculated on to food contact surfaces, such as stainless steel, polypropylene, and silicon, which was then treated with benzalkonium chloride, sodium hypochlorite, or ethanol as a sanitizer for 5minutes at $20^{\circ}C$. Results indicated that the type of surface had little affected the efficacy of various sanitizers. In addition, 200 ppm of benzalkonium chloride or 200 ppm of sodium hypochlorite showed no definite reduction of bacterial populations in the present of organic load, while 40% ethanol showed reduction to $4\;cfu\;\log_{10}$/carrier or more in viable count in the organic load.

• Journal of Food Hygiene and Safety
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• v.22 no.2
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• pp.99-104
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• 2007

To defend putrifaction of the processed rice cake from gas-forming yeast during storage and distribution it needed to reduce and remove them. The sanitizers of ethanol and organic acids were applied on Pichia anomala, Candida tropicalis, and isolated yeasts from the putrified cut rice cake. Although growth inhibition effect by the sanitizer of 20% ethanol, 1% acetic acid, or 1% lactic acid respectively were very low, the combined sanitizer of 20% ethanol and 1% acetic acid, or 1% lactic acid showed very high sterilizing effect toward the yeasts. Six log cfu/ml of the yeast was reduced with this combined sanitizers for 30 minutes. In addition, the combined sanitizer heated from 20 to $50^{\circ}C$ had more the increased sterility. Therefore, the sanitizer of the combined ethanol with the acetic acid or the lactic acid for 30 minutes at $50^{\circ}C$ might reduce or sterilize the putrifying yeast at the processed rice cake. The result might be also applied to the effective pre-treatment of many agricultural food stuffs, against yeast, especially unsterilized stuffs, without any hazards from the special sanitizers and nutritional loss from harsh sterilization.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.1042-1047
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• 2005

Effects of sanitizers and disinfectants on microorganisms in food-processing plants were investigated. Chlorine and hydrogen peroxide were most effective, showing approximately 2-3 log reductions, among products tested, whereas alcohol showed less than 1 log reduction. Before using sanitizer and disinfectant in food processing plants, aerobic plate, coliforms, and E. coli counts were about $10^1-10^5,\;10^1-10^2$, and below $10\;CFU/cm^2$, respectively. After use of sanitizer, APC decreased to $10^1-10^2$. The result to confirm sanitizing effectiveness for 2 months using showed that Alcohol compound, QAC, hydrogen peroxide compound were effective against Staphylococcus aureus ATCC 6538 and E. coli ATCC 10536 at recommended usage concentrations, whereas effectiveness of chlorine compound decreased from 8 to 4 log 2 weeks after opening of product. Although sanitizers and disinfectants approved by law showed 5 log reduction in vitro for S. aureus ATCC 6538 and E, coli ATCC 10536, sanitizing effectiveness in food processing plants was very low, and effectiveness decreased once used product was stored.

• Journal of Software Assessment and Valuation
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• v.16 no.1
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• pp.65-79
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• 2020

As Programmable Logic Controllers (PLCs), popular components in industrial control systems (ICS), are incorporated with the technologies such as micro-controllers, real-time operating systems, and communication capabilities. As the latest PLCs have been connected to the Internet, they are becoming a main target of cyber threats. This paper proposes two sanitizers that improve the security of uC/OS-II based firmware for a PLC. That is, we devise BU sanitizer for detecting out-of-bounds accesses to buffers and UaF sanitizer for fixing use-after-free bugs in the firmware. They can sanitize the binary firmware image generated in a desktop PC before downloading it to the PLC. The BU sanitizer can also detect the violation of control flow integrity using both call graph and symbols of functions in the firmware image. We have implemented the proposed two sanitizers as a prototype system on a PLC running uC/OS-II and demonstrated the effectiveness of them by performing experiments as well as comparing them with the existing sanitizers. These findings can be used to detect and mitigate unintended vulnerabilities during the firmware development phase.

• Safe Food
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• v.2 no.1
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• pp.38-47
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• 2007

• Food Quality and Culture
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• v.3 no.1
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• pp.34-39
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• 2009

This study assessed the efficacy of aqueous chlorine dioxide ($ClO_2$) and commercial chlorine sanitizer in terms of its ability to eliminate Listeria monocytogenes, Salmonella Typhimurium, and Escherichia coli O157:H7 on radish sprouts (Raphanus sativus L.). Radish sprouts were inoculated with a cocktail containing one each of three strains of three different foodborne pathogens, then treated with distilled water (control) or chemical sanitizers (100 ppm commercial chlorine, and 50, 100, 200 ppm $C1O_2$) for 1, 5, and 10 min at room temperature ($22{\pm}2^{\circ}C$). Populations of S. Typhimurium, E. coli O157:H7 and L. monocytogenes were counted at 4.64, 6.05, and 4.29 log CFU/g, respectively, after inoculation. Treatment with water did not significantly reduce the levels of any of the three foodborne pathogens. The levels of all three pathogens were reduced by treatment with chemical sanitizers; however, the observed levels of reduction of E. coli O157:H7 and L. monocytogenes were not significant as compared with the controls. The levels of the three pathogens were reduced most profoundly when treated for 10 min with 200 ppm of $C1O_2$, and the reduction levels of S. Typhimurium, E. coli O157:H7, and L. monocytogenes were 1.17, 1.63, and 0.96 log CFU/g, respectively. When chemically injured cells were investigated using SPRAB for E. coli O157 :H7 and by selective overlay methods for S. Typhimurium and L. monocytogenes, respectively, it was noted that commercial chlorine sanitizer generated more numbers of injured pathogens than did $C1O_2$. These data indicate that $C1O_2$ treatment may prove useful in reducing the numbers of pathogenic bacteria in radish sprouts.

• Food Science and Preservation
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• v.18 no.4
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• pp.429-435
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• 2011

The demand of packaged baby leaves has been increased for its convenient use as fresh-cut produce. This investigation was aimed to explore the effects of different sanitizers on the quality parameters of 'Tah Tasai' Chinese cabbage (Brassica campestris var. narinosa) baby leaves. Thirteen days old baby leaves were harvested and washed in tap water (TW), 100 ppm chlorine solution (Cl), 2 ppm ozonated water ($O_3$), 15 ppm chlorine dioxide solution ($ClO_2$) and washing with 0.2% citric acid solution followed by 50% ethanol spray (CA+Et). The samples were then packaged in 50 ${\mu}m$ polyethylene bags and stored at $5^{\circ}C$ for 10 days. Off-odor of packaged baby leaves was not detected during storage. There was no significant difference in color parameters among the treatments. Samples treated with $O_3$ showed substantially higher electrolyte leakage throughout the storage. This treatment also rendered a higher accumulation of $CO_2$ in the packages. Samples treated with Cl and CA+Et maintained good overall visual quality with higher scores compared to that of $O_3$ and $ClO_2$. Although Cl treatment showed lower number of total aerobic count at the beginning of storage, citric acid in combination with ethanol treatment was more effective until the end of storage. The combined treatment also showed comparatively lower coliform plate count. This result indicates that citric acid wash followed by ethanol spray could be an alternative to chlorine for environment friendly sanitization of baby leaves.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.671-677
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• 2005

Conformity to legal permission standard of $5\;log_{10}$ CFU/mL reduction of foodborne pathogens or spoilage bacteria such as Escherichia coli, Staphylococcus aureus, Salmonella typhimurium, Pseudomonas aruginosa, and Enterococcus hirae was examined in 11 domestic commercial sanitizers and disinfectant. One chlorine compound, two iodophor compounds, two peroxide compounds, and three quaternary ammonium compounds (QACs) met advised standard concentration (100%), showing $7\;log_{10}$ CFU/mL reduction, and met legal standard by $5-6\;log_{10}$ CFU/mL reduction at 75% of advised standard concentration. At 10% dilution, one chlorine compound, one iodophor compound, two peroxide compounds, and two QACs satisfied legal standard.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.1
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• pp.34-39
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• 2023

Objectives: In this study, the safety of alcohol-based hand sanitizers (ABHSs) for quasi-drugs and cosmetics was investigated by analyzing the ethanol content, which is an active ingredient with a sterilizing effect, and methanol, which is toxic. Methods: Forty-one ABHSs were purchased at large supermarkets and online stores. Ethanol quantification was performed by gas chromatography-flame ionization detector, and methanol quantification was performed by headspace-gas chromatography-mass spectrometry. Results: The ethanol content of ABHS in quasi-drugs was 49.6-67.8%, which was suitable for standard manufacturing procedures for external disinfectants, and the ethanol content of ABHS in cosmetics was 9.1-61.3%. The methanol content of ABHS in quasi-drugs ranged from not detected(N.D.)-131.8 ppm, which was suitable for the methanol detection standard of ethanol raw materials in the Korean Pharmacopoeia. The methanol content of ABHS in cosmetics was 23.4-859.7 ppm, which was suitable for the detection limit of methanol in cosmetics. Conclusions: The ethanol and methanol content of ABHS was judged to be safe. When selecting an ABHS to be used for sterilization, it seems necessary to check the content of ethanol, an active ingredient, and use it according to its intended purpose.