2012 Annual Report 1a.Objectives (from AD-416): ARS is interested in reducing food safety risks by improving fresh-cut produce wash operation. The Cooperator is interested in evaluating new anti-microbial agents on pathogen reduction. The Cooperator has the expertise and infrastructure to effectively conduct the proposed research activities. 1b.Approach (from AD-416): ARS will acquire the basic knowledge of the factors influencing sanitizer degradation, pathogen attachment and internalization during leafy greens and tomato wash process. The Cooperator will provide the expertise in chemistry, surface adsorption, and other characteristics in relation to sanitizer performance on pathogen reduction. 3.Progress Report: Both laboratory and pilot plant studies were performed to evaluate the effect of a novel produce wash aid, T128, for its ability to boost chlorine efficacy against pathogen survival and cross-contamination. Results indicate that T128 significantly increases the efficacy of chlorine on pathogen reduction on biofilms formed on stainless-steel surfaces, and cantaloupe rinds. T128 has been shown to be most effective at very low chlorine concentrations which occur primarily in the presence of high organic load. In separate studies, zein nanoparticles encapsulating two essential oils were evaluated for their physicochemical properties including morphology and chemical structure, as well as antioxidant and antimicrobial activities and their use in edible coatings on produce. Nanoparticles of zein were prepared using the liquid-liquid dispersion method to encapsulate the essential oils (EOs), thymol and carvacrol. The developed EO nanoparticles were found to be useful for incorporating in edible coatings for improving safety and quality of fresh and fresh-cut produce.