Evaluating the Effects of Ozone Nanobubble Treatments on Postharvest Quality of Fresh Peaches

Sanitation is a crucial postharvest operation that aims to reduce the microbiological load of harvested produce. Currently, in the southeastern United States, peach packing houses use chemical oxidizers, such as sodium hypochlorite (NaOCl) in their hydrocooling systems to treat the fruit and suppress foodborne pathogens postharvest. This study aims to evaluate the effectiveness and efficiency of a novel sanitation technology called high-oxygen water (HOW) as an alternative to NaOCl. It is based on the generation of stable nanobubbles of oxygen (O2) in water in combination with gaseous ozone (O3) without the need for chemicals. The suspended solution has the potential to reduce microorganism loads during the exposure period and prevent the growth of microorganisms during storage. This technology could serve as an effective sanitation treatment for peaches during hydrocooling. Peaches were treated using HOW at various concentrations of dissolved oxygen (10, 20, and 30 mg<middle dot>L-1) combined with saturated (approximately 8 mg<middle dot>L-1) O3. These treatments were compared with a standard NaOCl treatment (50 mg<middle dot>L-1 of free chlorine). Our team evaluated the effects of HOW by assessing postharvest fruit quality changes and decay incidence over time. The results indicated that while HOW treatments showed potential in maintaining postharvest quality, high concentrations of O3 were detrimental to fruit quality, causing increased decay incidence compared with the NaOCl treatment.