Evaluation of different methods for determination of properties of chlorine-based sanitizers

Chlorine-based sanitizers, such as electrolyzed oxidizing (EO) water, are used for the sanitation of food contact surfaces and the prevention of cross contamination in various food processing settings. Several different chlorine species are present in EO water, and these chlorine species are important to the antimicrobial efficacy. Measurements of free and total chlorine, hypochlorous acid (HOCl), hypochlorite ion (OCl−) and chloride were conducted on chlorinated water and EO water solutions using a variety of commercially available methods. The chlorinated and EO water solutions differed by pH, initial free chlorine concentration, chloride concentration and organic compound concentration. It was discovered that these factors influenced the methods used to measure the various chlorine species by differing amounts. The data from this study will help in determining the appropriate methods of measuring free chlorine, total chlorine and chloride in chlorine-based sanitizers under various conditions.

► Different methods of chlorine species quantification were compared. ► Determination of specific free chlorine species was affected by organic materials. ► Chloride determination method performance is pH and concentration dependent. ► Suggested methods from this study can be used for hypochlorite solutions and electrolyzed water.