In a similar vein, Cyclopss Corp., Salt Lake City, has developed a 12-in. cylindrical countertop appliance that infuses about 1.7 gal. of water with ozone at about 0.3 ppm. Equipped with a colander, the device is designed for soaking fruits, vegetables and poultry. Cyclopss, which develops ozone-based technology then licenses it for manufacturing, expects the unit to become available within the next six months and to cost under $100. The company is also working on an under the counter, dual use ozone unit that produces ozonated water for sanitizing purposes and potable water whose ozone is removed by a carbon filter after purification.

Consumers are expected to warm up to ozone once they learn it is already widely used in municipal water treatment, food processing, and bottled water. As an oxidizing agent, ozone is 1.5 times more powerful than chlorine. Ozone kills bacteria, viruses and protozoa immediately on contact, much faster than chlorine. And because ozone works by dismantling the cell membranes, microorganisms cannot develop a resistance to it. That’s an important feature, given the discovery of chlorine-resistant strains of Cryptosporidium and Giardia, both of which have caused deaths in recent years. Some research suggests that ozone can also destroy molds and pesticide residue. And though it’s a powerful disinfectant, unused ozone soon reverts to ordinary oxygen (O2), leaving no residue or byproducts.

Ozone’s disappearing act (it has a half-life of only 20 min.), while seen as a virtue by proponents, is perceived as a drawback by others who would prefer a more stable disinfectant. One alternative under serious consideration is electrolyzed oxidizing (EO) water. Machines that produce EO water have just come on the market in the U.S.

The ROX 20TA-U water electrolyzer, sold by Hoshizaki America, Peachtree City, Ga., is aimed the commercial market—foodservice operations, hotels, hospitals, etc. Several restaurant chains are already evaluating ROX equipment in their test kitchens. The compact ROX machine (run on standard 110 V) takes ordinary tap water and a small amount of simple salt (NaCl at 0.01 percent solution), and uses electrolysis and a separating membrane to create two types of water—alkaline (11.3 pH and up) and acidic (2.7 pH and lower).

The alkaline water, which contains about 30 ppm of sodium hydroxide (NaOH), is used for cleaning and degreasing. The acidic water, which contains about 30 ppm hypochlorous acid (HOCl), has a powerful bactericidal effect and is used for sanitizing. The acidic water can be used directly on meats, fruits and vegetables, without changing taste or quality, and can also be used to sanitize cutting boards, countertops, utensils, etc. Research at Auburn University and the University of Georgia have demonstrated the ability of EO water to inactivate a number of foodborne pathogens such as E. Coli O157:H7, Listeria, and Salmonella. Hoshizaki says that uncovered EO water (kept out of sunlight) maintains its efficacy for several days, and that storing it in an airtight container keeps it for up to 30 days.

Yen-Con Hung, a professor at the University of Georgia who has performed extensive research in this area, has found that, in some cases, EO water can kill bacteria more effectively than chlorinated water. He notes that, when comparing the two solutions, there is a difference in oxidation reduction potential, even when they both have the same chlorine concentration. That’s because EO water contains additional oxidants, which is one of the a features that Hung’s research group is investigating. They are also exploring different means for optimizing the production of EO water. Results of Hung’s EO water research have been published in several scientific journals and was presented at last year’s annual meeting of the American Chemical Society.

Regardless of whether EO water has a microbiocidal edge over chlorinated water, the primary advantage of EO water is that it can be easily generated at the point of use, eliminating the need to manufacture, transport, store and mix disinfectant chemicals. The issue of accurate mixing of chemicals is of particular concern to the foodservice industry, where high employee turnover undermines training efforts.

Hung believes that once EO water generators become accepted in the commercial sector, lower cost home versions will likely emerge. The core technology is fairly simple, he notes, it’s just a matter of higher volumes driving down costs.