36E-37 |
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C. J. DOONA1, F. E. Feeherry1, and K. Kustin2. (1) U.S. Army Natick Soldier Center, U.S. Army Research, Development and Engineering Command, Combat Feeding Innovative Science Team, Kansas St., Bldg. 36, Rm. E-108, Natick, MA 01760, (2) Dept. of Chemistry - Emeritus, Brandeis Univ., South St, Waltham, MA 02254 Globalization of the supply chain for Fresh Fruits and Vegetables (FFVs) requires extending shelf-life by eliminating contaminating pathogens and spoilage microorganisms. Chlorine dioxide is a broad-based biocide that is commonly used in aqueous sprays or washes to preserve FFVs or to disinfect food processing equipment. Technologies that controllably generate chlorine dioxide in situ warrant exploration for their ability to enhance microbial destruction and extend shelf-life. We evaluate a novel chemical system for its ability to generate chlorine dioxide gas in a closed container and eliminate harmful pathogens and tough-to-kill spores. Specifically, we manipulate the rates of chlorine dioxide formation by this chemical system to ensure the inactivation of Listeria monocytogenes (LM), Escherichia coli (EC), Staphylococcus aureus (SA), and spores of Bacillus stearothermophilus (BT). Inoculated suspensions of LM, EC, and SA cells or BT spores (106 - 108 CFU/mL) were exposed to chlorine dioxide gas chemically generated at low temperatures (< 55° C) and humidities in a closed container. Samples were exposed to various concentrations of biocide and for various times. Surviving colonies were enumerated using the appropriate recovery media. Chlorine dioxide gas generated in situ (ppm to millimolar levels) eliminated contaminating pathogens and spores (> 106) in 2 to 60 minutes of exposure depending on the reaction conditions. SA was the least resistant microorganism, and BT was the most resistant to chlorine dioxide. Biological indicator vials and swab kits confirmed the capability of chlorine dioxide to eliminate BT spores on surfaces, similar to its effects on the surfaces of FFVs. Chemically-generated chlorine dioxide gas is a broad-based biocide that can efficiently eliminate high inoculum levels in a closed container device. This apparatus can be used in place of liquid sprays or washes to rapidly decontaminate surfaces and ensure the microbiological safety and extended shelf-life of globally-distributed FFVs.
Session 36E, Fruit & Vegetable Products: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |