Surface Decontamination of Fresh Produce

摘要

This study was designed to assess the efficacy of dissolved ozone (O3)rnin its role in the decontamination of fresh produce in both one and twornstage wash processes. Lettuce (‘Fiorella') was inoculated with arncombination of Escherichia coli, Listeria monocytogenes, Salmonellarncholeraesuis and Bacillus cereus. The inoculated lettuce was treated atrn1.5 ppm dissolved [O3]. The highest level of sensitivity was attributablernto L. monocytogenes during a two-stage wash process resulting in a 4-rnlog reduction in comparison with a 0.7 log reduction in the one-stagernwash process. Population reductions of B. cereus also improved withrnthe two-stage process with log reductions of 1.8. Log populationrnreductions of 1.1 were achieved for S. choleraesuis. E. coli proved thernmost resistant with reductions of only 0.2 log in the two-stage processrnachievable. Though reductions in bacterial numbers are achievable withrnthe use of a one-stage wash process, the efficacy of dissolved O3 is farrngreater when used in conjunction with an initial washing step to removernminimal amounts of bacteria and other organic debris.