TY - JOUR TI - Feasibility study of novel gaseous chlorine dioxide generating method for pathogen inhibition on fresh produce DO - https://doi.org/doi:10.7282/T3CZ391G PY - 2015 AB - Based on the understanding of its generating mechanisms, this research hypothesized a novel method of ClO2(g) generation that utilizes two of the major respiration products (i.e. CO2 and moisture) naturally released from fresh produce to provide H2CO3, react with NaClO2 and generate ClO2(g). Through four consecutive experiments, this hypothesis was primarily demonstrated. Then, the basic chemistry and microbiology mechanisms related to this hypothesis were further investigated. This research demonstrated that only when the three components (i.e. CO2, moisture and NaClO2) existed in the system, ClO2(g) could be generated and exhibit complete inhibition effects against Salmonella spp. The impact of different factors including NaClO2 content, CO2 content, RH content, temperature and light conditions in the release profile of ClO2(g) and the inhibition effects against Salmonella spp. were systematically investigated. The basic chemistry mechanisms including the relationship between pH and ClO2 generation profile as well as the microbiology mechanisms including "D value" and "Z value" were obtained. To help practically apply this demonstrated hypothesis, two easy-to-use delivery systems for NaClO2 as Tyvek sachet and gum arabic paste were developed. The successful generation of ClO2(g) from both systems were confirmed through analytical methods directly and microbial inhibition experiments indirectly. The complete inhibition effects from Tyvek sachet and gum arabic paste against Salmonella spp. using real fresh tomato as the source of CO2 and moisture were observed. For Tyvek sachet, the optimal amount of NaClO2 needed in the delivery system was determined. Besides the two easy-to-use delivery systems, a promising delivery system for NaClO2 as electrospun fiber was also developed. The physical properties of different polyethylene oxide (PEO) and NaClO2 water solutions as well as the morphology and diameter distribution of fibers electrospun from these solutions were obtained and analyzed. The successful loading of NaClO2 onto the electrospun fiber was observed by scanning electron microcopy (SEM) images and the loading efficiency was calculated to be 83.9% (±3.3%). The microbial inhibition effects from electrospun fiber against Salmonella spp. was observed both under simulated conditions as well as on the surface of real fresh tomato. KW - Food Science KW - Chlorine dioxide KW - Food contamination--Prevention LA - eng ER -