Tuesday, November 10, 2015


Controlling Salmonella cross-contamination in tomatoes


Tomato Best Management Practices require Florida packers to treat tomatoes in a flume system containing at least 150 ppm of free chlorine or other approved sanitizer.

tomato.traceabilityHowever, research is needed to determine the ability of these sanitizers to prevent the transfer of pathogens from contaminated to uncontaminated tomatoes, particularly under realistic packinghouse conditions.

The goal of this research was to assess the minimum levels of sanitizer needed to prevent Salmonella cross-contamination between tomatoes in a model flume system under clean conditions and conditions where organic matter was added.

Inoculated tomatoes (ca. 8.3 log CFU per tomato) were treated along with uninoculated tomatoes in a model flume system containing 0, 10, or 25 ppm of hypochlorous acid (HOCl) under organic loading conditions of 0, 500, or 4,000 ppm of chemical oxygen demand (COD). In the absence of HOCl, uninoculated tomatoes were highly contaminated (ca. 5 log CFU per tomato) by 15 s. No contamination was detectable (

log CFU per tomato) on uninoculated tomatoes when HOCl was present, except with 10 ppm at 4,000 ppm of COD, suggesting failure of 10 ppm of HOCl as a sanitizer under very high organic loading conditions. In the presence of HOCl or peroxyacetic acid, Salmonella was undetectable (

Further validation in a larger commercial setting and using higher organic loading levels is necessary because managing HOCl at this low concentration is difficult, especially in a recirculating system. The use of less sanitizer by packers could reduce chemical and disposal costs.

Control of Salmonella Cross-Contamination between Green Round Tomatoes in a Model Flume System

Implementing Ecolox 240 or Ecolox 1200 in your flume system will prevent the cross contamination between tomatoes and maintain a more healthy environment for workers!