Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/30/2014
Publication Date: 11/7/2014
Citation: Olanya, O.M., Annous, B.A. 2014. Combining biocontrol with chlorine dioxide and other intervention technologies for inactivation of foodborne pathogens on produce. Attendance and presentation @ 9th Dubai International Food Safety Conference.Meeting Abstract. 11/9-11/2014, Dubai Conference Center, Dubai, United Arab Emirates.
Technical Abstract: Produce contamination incited by Salmonella enterica, Escherichia coli O157:H7 and Listeria monocytogenes are of considerable importance to food safety. Post-harvest intervention measures can reduce or eliminate contamination and enhance food safety. In this reserach, the effectiveness of biocontrol microbes and gas-phase antimicrobials (chlorine dioxide) on the survival and inactivation of foodborne pathogens were investigated on produce. The efficacy of Pseudomonas chlororaphis (Pc) and P. fluorescens (Pf) for biocontrol of Salmonella enterica serovars Montevideo, Typhimurium and Poona on spot-inoculated tomatoes were evaluated. Subsequent to the application of Pc or Pf on stem scars of tomatoes, these were inoculated with the Salmonella serovars listed above. Similarly, tomatoes previously inoculated with Salmonella strains were stored at 13 deg C, prior to treatment with 0.4 mg/L of gaseous chlorine dioxide for 2 and 4 hrs, respectively. The application of P. chlororaphis on produce reduced Salmonella serovars from 5.83 (untreated control) to 2.59 log CFU/g of bacteria. Gaseous chlorine dioxide was more efficacious for inactivation of Salmonella on tomatoes. At 4 hrs of gaseous chlorine dioxide treatment (0.4 mg/L, 90% R.H., at 13 deg C), the populations of S. Montevideo and S. Typhimurium that survived were 0.82 and less than 0.01 log CFU/g of produce respectively; relative to bacterial numbers of 5.42 and 5.37 log CFU/g of produce for the untreated control. The survival of pathogenic bacteria exposed to chlorine dioxide at 2 hrs was similar to 4 hrs. Post-harvest application of chlorine dioxide and sequential protection by P. chlororaphis as well as other intervention technologies can enhance control of Salmonella and other foodborne pathogens on produce.