• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1337-1342
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• 2008

This study was conducted to investigate effects of chemical sanitizers on inhibiting foodborne pathogens, such as Listeria monocytogenes (L. monocytogenes), Salmonella Typhimurium (S. Typhimurium), and E scherichia coli O157:H7 (E. coli O157:H7), on cabbages. Cabbages were inoculated with the culture cocktail of pathogens and treated with water, 100 ppm commercial chlorine, and 50, 100, and 200 ppm chlorine dioxide ($ClO_2$) for 1, 5, and 10 min at room temperature ($22{\pm}2^{\circ}C$). Treatments with water did not significantly reduce levels of three pathogens whereas other treatments with chemical sanitizers significantly reduced levels of three pathogens. Treatment with 200 ppm $ClO_2$ for 10 min was the most effective at inhibiting pathogens and reduction levels were 1.90, 1.92, and 1.98 log CFU/g for L. monocytogens, S. Typhimurium, and E. coli O157:H7, respectively. Levels of reduction were increased with the increase of $ClO_2$ concentrations. When chemically injured cells were investigated, there were no significant differences on the levels of injured cells between before and after treatment with commercial chlorine and $ClO_2$. These results suggest that $ClO_2$ can be used as an alternative sanitizer for reducing pathogens on fresh produces.

• Korean journal of food and cookery science
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• v.24 no.4
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• pp.445-451
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• 2008

This study compared the effects of chlorine dioxide and a commercial chlorine sanitizer for inhibiting foodborne pathogens, including Salmonella enterica serovar Typhimurium, Listeria monocytogenes, and Escherichia coli O157 : H7, on lettuce leaves. The lettuce samples were inoculated with each cocktail of the three strains, and were then treated with chemical sanitizers [distilled water, 100 ppm commercial chlorine and 50 ppm, 100 ppm, 200 ppm chlorine dioxide ($ClO_2$)] for 1 min, 5 min, and 10 min at room temperature($22{\pm}2^{\circ}C$). Following inoculation of the leaves, initial populations of E. coli O157:H7, L. monocytogenes, and S. Typhimurium were approximately 5.54, 4.47, and 5.12 log CFU/g, respectively these levels were not significantly reduced by the treatment with water,whereas the 100 ppm commercial chlorine sanitizer treatment and $ClO_2$ (at all tested concentrations) were effective at reducing levels of all three pathogens. The treatment of 200 ppm $ClO_2$ for 10 min was most effective at inhibiting the three pathogens, and reduction levels of E. coli O157 : H7, L. monocytogenes, and S. Typhimurium were 2.28, 1.95, 1.76 log, respectively. The inhibitory effect of $ClO_2$ increased with increasing treatment concentration of $ClO_2$, but there was no significant difference by the treatment times. When chemically injured cells of E. coli O157 : H7 and L. monocytogenes and S. Typhimurium were examined by SPRAB and selective overlay methods, respectively, it was observed that the commercial chlorine sanitizer generated greater numbers of injured L. monocytogenes than the $ClO_2$ treatment. From the overall results, $ClO_2$ was more effective at inhibiting pathogenic bacteria compared to the commercial chlorine sanitizer therefore, it has potential to be utilized as an alternative sanitizer to increase the microbial safety of fresh produce.