Improved Pathogen Neutralization Through Nanobubbles

The major goal of this project is to validate the effectiveness of a high concentration nanobubble wash solution at cleaning postharvest fresh produce by demonstrating its novel pathogen inactivation or pathogen washing capabilities when compared to standard wash procedures and pathogen inactivation methodologies. To meet this goal, we have established the following Objectives:Conduct a series of discrete pathogen inactivation studies on the surfaces of inoculated leafy greens in wash water charged with nanobubbles. Variables will be: (i) gas mixture in the nanobubbles (ozone, nitrogen, oxygen, carbon-dioxide, air, and/or mixtures of the same); (ii) target pathogen (Salmonella,EscherichiacoliO157:H7, andListeriamonocytogenes);(iii) concentration of gas in the wash water (ranging up to 20ppm); and (iv) contact times (ranging from 30 seconds to 5 minutes). Measured outputs will be number and log reduction of pathogens on inoculated leaves.Conduct a series of discrete pathogen shedding studies from the surfaces of inoculated leafy greens in wash water charged with nanobubbles. Variables will be as set forth in Objective 1. Measured outputs will be the number and viability of pathogens in wash water sampled immediately after washing.Conduct a series of studies to measure the ability of high concentration nanobubble wash water to inactivate pathogens shed from inoculated leafy greens. Variables will be as set forth in Objective 1. Measured outputs will be the number and viability of pathogens in wash water sampled at various time intervals following introduction of the target pathogen to the wash water.Conduct appropriate control studies using chlorine wash water consistent with standard commercial-scale chlorine wash systems and methods.Should resources and time permit, conduct studies as set forth in Objectives 1 through 3 with additional produce types such as vine stock vegetables and/or root vegetables.