• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.492-499
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• 2017

Combined treatment with gaseous and aqueous chlorine dioxide ($ClO_2$) was performed to improve the microbiological safety and quality of paprika. A single treatment of 50 ppmv $ClO_2$ gas for 30 min decreased the populations of Escherichia coli O157:H7 and Salmonella Typhimurium by 2.33 and 2.91 log CFU/g, respectively. In addition, a single treatment of aqueous $ClO_2$ (50 ppm) for 5 min decreased these populations by 1.86 and 1.37, respectively. The most dramatic effects were achieved by combined treatment of 50 ppm aqueous and gaseous $ClO_2$ for 30 min, which decreased populations of E. coli O157:H7 and S. Typhimurium by 4.11 and 3.61 log CFU/g, respectively. With regard to the qualities of paprika, no adverse effects were elicited by the combined treatment. Thus, combined treatment with aqueous and gaseous $ClO_2$ is a suitable approach that can be used to improve the microbial safety and quality of paprika.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.181-184
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• 2007

Effect of aqueous chlorine dioxide ($ClO_{2}$) treatment on quality change of mackerel during storage was examined. Mackerel treated with 0, 5, 10, and 50 ppm of $ClO_{2}$ solution, respectively was stored at $4^{\circ}C$. $ClO_{2}$ treatment decreased populations of aerobic bacteria in mackerel during storage. The number of total aerobic bacteria of mackerel treated with 50 ppm $ClO_{2}$ increased from 2.45 to 3.44 log CFU/g after 9 days of storage, while that of the control increased from 3.47 to 4.72 log CFU/g. The pH values of mackerel increased during storage, with no significant changes among treatments. Volatile basic nitrogen values of mackerel were decreased by $ClO_{2}$ treatment. Quality of mackerel treated with $ClO_{2}$ was better than that of the control during storage based on sensory evaluation. These results indicate that aqueous $ClO_{2}$ treatment could be useful for improving the microbial safety and qualities of mackerel.

• Food Science and Preservation
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• v.18 no.3
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• pp.423-428
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• 2011

Inactivation kinetic data of Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, Salmonella Typhimurium, and Salmonella Enteritidis via treatment with aqueous chlorine dioxide treatment at a specific concentration were evaluated using the first-order kinetic and Weibull models. The Weibull model showed a better fit with the kinetic data than the first-order kinetic model. The survival curves after the aqueous chlorine dioxide treatment showed $t_R$ values(time required to reduce microbial populations by 90%) of 2.49 min for E. coli O157:H7 at 5 ppm, 1.47 min for L. monocytogenes at 5 ppm, 0.94 min for S. aureus at 5 ppm, 0.87 min for S. Typhimurium at 1 ppm, and 0.08 min for S. Enteritidis at 1 ppm, according to the Weibull model.

• Preventive Nutrition and Food Science
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• v.13 no.1
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• pp.45-50
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• 2008

The effect of aqueous chlorine dioxide ($ClO_2$) treatment on microbial growth and quality of chicken leg during storage was examined. Chicken leg samples were treated with 0, 50, and 100 ppm of $ClO_2$ solution and stored at $4^{\circ}C$. Aqueous $ClO_2$ treatment significantly decreased the populations of total aerobic bacteria, yeast and mold, and coliforms in chicken leg. One hundred ppm $ClO_2$ treatment reduced the initial populations of total aerobic bacteria, yeast and mold, and coliforms by 0.93, 1.15, and 0.94 log CFU/g, respectively. The pH and volatile basic nitrogen values in the chicken leg decreased with increasing aqueous $ClO_2$ concentration, while concentrations thiobarbituric acid reactive substances (TBARS) increased during storage regardless of aqueous $ClO_2$ concentration. Sensory evaluation results revealed that the quality of the chicken leg treated with aqueous $ClO_2$ during storage was better than that of the control. These results indicate that aqueous $ClO_2$ treatment can be useful for improving the microbial safety of chicken leg during storage.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.129-133
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• 2005

Aqueous chlorine dioxide and citric acid treatment was introduced to insure microbial safety of minimally processed and refrigerated (MPR) salad. Salad samples were treated with 50 ppm chlorine dioxide and 1% citric acid. Chemical treatment decreased total aerobic bacteria, yeast and molds, E. coli, and Listeria by 3.75, 3.47, 3.41, and 3.38 log cycles, respectively, and polyphenoloxidase activity of MPR salad by 49.73%. Plain water washing of salads did not effectively decrease microbial growth. These results indicate appropriate chemical treatment provides microbial safety and quality control in MPR salad during marketing.

• Food Science and Preservation
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• v.15 no.2
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• pp.236-242
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• 2008

We investigated the optimum concentration of a $NaClO_2$ solution and the amount of gaseous $Cl_2$ for production of high yield and purity of aqueous $ClO_2$ by use of a gaseous chlorine-chlorite $ClO_2$ generator. This system produced lower concentrations of chlorine dioxide and is applicable for direct-use in food processing as a cleaner and sanitizer. The concentration of $NaClO_2$ solution and the amount of gaseous $Cl_2$ was varied from 0.01-0.1% and 100-1,000 g/hr, respectively. The concentrations of chlorite, chlorate, FAC (free available chlorine), and chlorine dioxide that were produced increased with increasing concentration of $NaClO_2$ solution and with the amount of gaseous $Cl_2$. The optimum concentration of $NaClO_2$ solution and amount of gaseous $Cl_2$ were 0.1% and 900 g/hr respectively. $ClO_2$ and FAC produced at these concentrations were 882.0 ppm and 8.0 ppm, with no detection of chlorite and chlorate. The yield and purity of $ClO_2$ were 97.0% and 96.0% respectively. Immersion-cleaning experiments showed that this protocol decreased the level of CFU/g by $10^3$- to $10^4$-fold, with a similar effect on fruit.

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.11a
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• pp.153-153
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• 2020

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.296-300
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• 2009

Generation of chlorine dioxide ($ClO_2$) was studied by the un-divided electrochemical cell system using $RuO_2$ anode material. Sodium chlorite ($NaClO_2$) was used as a precursor compound of chlorine dioxide. Effect of various operating parameters such as feed solution flow rate, initial solution pH, $NaClO_2$ and NaCl conc., and applied current density on the produced chlorine dioxide concentration and solution pH were investigated in un-divided electrochemical cell system. Produced chlorine dioxide concentration and solution pH were strongly depends on the initial solution pH and feed solution flow rate. Sodium chloride (NaCl) was not only good electrolyte, it was also used as a raw material of chlorine dioxide with $NaClO_2$. Observed optimum conditions were flow rate of feed solution (90 mL/min), initial pH (2.3), $NaClO_2$ concentration (4.7 mM), NaCl concentration (100 mM), and current density ($5A/dm^2$). Produced chlorine dioxide concentration was around 350 mg/L and solution pH was around 3.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1886-1891
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• 2013

To inactivate the microorganisms on the surface of blueberries after harvest and to secure microbial safety, a bubble-aqueous chlorine dioxide washing system was developed. After treating the freshly prepared blueberries with the bubble-aqueous chlorine dioxide washing system, the changes in the microbial populations and quality of the blueberries were determined during storage $4{\pm}1^{\circ}C$. Microbiological data indicated that the populations of total aerobic bacteria, yeast and mold decreased by 1.4 and 1.3 log CFU/g at the treatment of 20 ppm aqueous chlorine dioxide with the system, respectively. There was no significant difference in color change and weight loss during storage among treatments. In addition, this washing system could handle approximately 60 kg of blueberry per hour, resulting in labor-saving. Therefore, these results clearly suggest that the bubble-aqueous chlorine dioxide washing system could be useful in improving the microbiological safety of fresh blueberries after harvest.

• 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.