ARS | Publication request: Surface decontamination technologies for enhancing safety and shelf life of cantaloupe

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 20, 2012
Publication Date: May 1, 2012
Citation: Annous, B.A., Burke, A.M., Sites, J.E. 2012. Surface decontamination technologies for enhancing safety and shelf life of cantaloupe [abstract]. 2012 United Fresh Produce Association and Multi-State Project S294 Annual Meeting. May 1-3, 2012, Dallas, Texas. 1:1.

Technical Abstract: Cantaloupes have been implicated in six outbreaks of salmonellosis that resulted in over 800 cases and two deaths in the U.S. since 1990. A recent multi-state outbreak of Listeria monocytogenes infection in the U.S. resulting in at least 146 illnesses and 30 deaths in 2011 came from contaminated cantaloupe. Also, Commercial washing processes for cantaloupes are critical step for minimizing cross contamination. However, these processes are limited in their ability to inactivate and/or remove Salmonella on the cantaloupe rind, due to biofilm formation and inaccessibility of microbial attachment sites to washing systems. The objective was to develop surface decontamination technologies capable of reaching and inactivating Salmonella within biofilms or attached to inaccessible sites on artificially contaminated cantaloupe surfaces. Whole cantaloupes, surface inoculated with Salmonella Poona RM 2350 to an approximate final concentration of 5-6 log CFU/cm2, were stored at 4 deg C for 24 h prior to treatment. Inoculated cantaloupes were submerged in hot water at 76 deg C for 3 min or treated with up to 2 mg/l ClO2 gas for up to 6 h in a closed chamber that was developed at ERRC. Following treatment, residual populations of S. Poona on whole cantaloupe rinds were enumerated using XLT-4 selective agar medium. There was in excess of 5 log CFU/cm2 reduction in S. Poona populations following hot water or ClO2 gas treatments. Both treatments extended the shelf life of the cantaloupes at 4 deg C by reducing the population of spoilage microorganisms on the rind surface, and had no adverse effects on the quality of the melon. These studies demonstrated that both technologies were highly effective in inactivating S. Poona attached to inaccessible sites on the cantaloupe rind.