Evaluation of Chlorine Dioxide Gas Residues on Selected Food Produce

In recent years, the consumption of fresh fruits and vegetables has greatly increased, and so has its association with contamination of several foodborne pathogens (Listeria, Salmonella, and Escherichia coli). Hence, there is a need to investigate effective sanitizer systems for produce decontamination. Chlorine dioxide (ClO2), a strong oxidizing gas with broad spectrum and sanitizing properties, has previously been studied for use on selected fruits and vegetables. ClO2 gas treatments show great potential for surface pathogen reduction; however its use from a residue safety standpoint has yet to be assessed. Thus, the objective of this study was to evaluate residues of ClO2, chlorite, chlorate, and chloride on selected fresh produce surfaces after treatment with ClO2 gas. A rinse procedure was used and water samples were analyzed by N, N-diethyl-p-phenylenediamine and ion chromatography method (300.0). Seven different foods-tomatoes, oranges, apples, strawberries, lettuce, alfalfa sprouts, and cantaloupe-were analyzed after ClO2 treatment for surface residues. Very low residues were detectable for all the food products except lettuce and alfalfa sprouts, where the measured concentrations were significantly higher. Chlorine dioxide technology leaves minimal to no detectable chemical residues in several food products, thus result in no significant risks to consumers.