Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 10, 2005
Publication Date: July 15, 2005
Citation: Annous, B.A. 2005. Inactivation of salmonella on cantaloupe surfaces using chlorine dioxide gas treatment (abstract). Institute of Food Technologists. http://ift.confex.com/ift/2005/techprogram/paper_30689.htm. Technical Abstract: Cantaloupes have been implicated in six outbreaks of salmonellosis in the U.S. since 1990. Previous research in our laboratory has documented the inadequacy of washing processes to inactivate and/or remove microorganisms on cantaloupes, including human pathogens, due to biofilm formation and inaccessibility of microbial attachment sites to washing systems. The objective was to develop a chlorine dioxide gas (ClO2) treatment capable of reaching and inactivating human pathogens within biofilms or attached to inaccessible sites on cantaloupe surfaces. Cantaloupes were inoculated with Salmonella Poona RM 2350 to an approximate final concentration of 6 log CFU/cm2, and stored at 4°C for 24 h prior to treatment. Cantaloupes were fumigated with ClO2 for up to 6 h in a closed chamber that was developed at ERRC, using two different technologies for generating ClO2. Following treatment, residual populations of Salmonella Poona on whole cantaloupe rinds were enumerated using XLT-4 selective agar medium. There was in excess of 4.5 log CFU/cm2 reduction in Salmonella Poona populations following ClO2 treatment for 6 h. Population reductions following ClO2 treatments were similar irrespective of the technology used for generating ClO2 gas. The treatment increased the shelf life of the cantaloupes by reducing spoilage microorganism populations on the rind surface, and did not seem to have adverse effects on the quality of this commodity. The work presented here showed that ClO2 gas treatment of cantaloupes is able to inactivate Salmonella Poona attached to inaccessible sites on the rind or within biofilms. Also, this treatment was shown to extend the shelf life at 4°C and had no adverse effects on the quality of the melon.