Efficacy of aqueous chlorine dioxide and fumaric acid for inactivating pre-existing microorganisms and Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes on broccoli sprouts

The combined effect of aqueous chlorine dioxide (ClO2) and fumaric acid as a chemical treatment to inactivate pre-existing microorganisms was evaluated using broccoli sprouts. Broccoli sprouts were treated with distilled water, 50 ppm ClO2, 0.5% fumaric acid, and a combination of 0.5% fumaric acid and 50 ppm ClO2. Treatment with 50 ppm ClO2 and 0.5% fumaric acid reduced the initial populations of total aerobic bacteria, yeasts and molds, and coliforms in broccoli sprouts by 2.70, 2.46, and 1.71 log CFU/g, respectively. In addition, the combined treatment of 50 ppm ClO2 and 0.5% fumaric acid reduced the initial populations of Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes inoculated on broccoli sprouts by 2.39, 2.74, and 2.65 log CFU/g, respectively, compared to the control. These results suggest that the combination of aqueous ClO2 and fumaric acid can be useful as a hurdle for extending the shelf life of broccoli sprouts during storage. (C) 2008 Elsevier Ltd. All rights reserved.