Antimicrobial efficacy of gaseous chlorine dioxide against Salmonella enterica Typhimurium on grape tomato (Lycopersicon esculentum)

Abstract

Summary The aim of this study was to investigate the effects of gas level and treatment condition on antimicrobial efficacy of ClO2 gas against Salmonella enterica Typhimurium on grape tomato (Lycopersicon esculentum). Grape tomatoes were dip‐inoculated with inoculum of S. enterica Typhimurium TISTR 292 (ATCC 13311) (9.79 ± 0.39 log CFU mL−1) and allowed to dry before treatments. The pre‐inoculated samples were exposed to 0.15–0.85 mg of ClO2 gas, for up to 58 min. The treatments at 4 and 25 °C resulted in population reductions of S. enterica Typhimurium of up to 3.95 ± 0.22 and 7.37 ± 0.39 log CFU per fruit, respectively. The population reduction results were used to construct statistical models to predict efficacy of ClO2 gas. The second‐order equations for treatments at 4 and 25 °C had R2 of 0.87 and 0.95, respectively, and indicated that efficacy of ClO2 gas was significantly influenced by ClO2 gas level, exposure time and treatment temperature.

Fresh Produce Safety and Quality: Chlorine Dioxide’s Role

“…Several studies have investigated the disinfection of tomatoes using ClO 2 ( Praeger et al, 2018 ; Sun et al, 2019 ). For artificially inoculated human pathogens, 5–7 log reduction in microbial load has been observed with gaseous ClO 2 concentrations < 1 ppm ( Bhagat et al, 2010 ; Olanya et al, 2015 ; Netramai et al, 2016 ). For instance, a 12 min exposure to 0.5 ppm ClO 2 resulted in >5 log reduction in Salmonella and L. monocytogenes loads in hydroponically grown tomatoes ( Bhagat et al, 2010 ).…”

“…For instance, a 12 min exposure to 0.5 ppm ClO 2 resulted in >5 log reduction in Salmonella and L. monocytogenes loads in hydroponically grown tomatoes ( Bhagat et al, 2010 ). With an increased exposure time (approximately 1 h), grape tomatoes exhibited >7 log reduction in the load of Salmonella spp., at 25°C ( Netramai et al, 2016 ). Trinetta et al (2010) evaluated the efficacy of short-term exposure of high ClO 2 concentrations in the inactivation of S. enterica inoculated on tomatoes and observed that the initial populations (6 log) were reduced to 3 log, 2 log, and 1 log in response to 8 ppm ClO 2 for 60 s, 10 ppm ClO 2 for 120 s, and 10 ppm for 180 s, respectively.…”

Generation, mechanisms, kinetics, and effects of gaseous chlorine dioxide in food preservation

“…Hydrochloric acids (Netramai et al., 2016; Simonet & Gantzer, 2006), sulfuric acids (H. Lee et al., 2018), phosphoric acids (Rodgers et al., 2004), and citric acids (Kingsley et al., 2018; Young & Setlow, 2003) have all been used to generate hydrogen ions. However, volatility, byproducts, and generation rate are the major concerns for these activators.…”

“…Schematic diagrams of different gaseous ClO 2 treatment systems: (A) gaseous ClO 2 cabinet with fan (S.‐Y. Lee et al., 2006); (B) climatic chamber with ClO 2 packaging film (Netramai et al., 2016); (C) gaseous ClO 2 chamber with injection port and ClO 2 reservoir (Zhang et al., 2019); and (D) test chamber for ClO 2 inactivation (S.‐H. Park & Kang, 2015).…”

“…The embedded touch screen or attached measuring devices can be used to monitor real time ClO 2 concentrations (Annous et al, 2020;S.-H. Park & Kang, 2018). Regarding the fumigation process, gaseous ClO 2 can either spontaneously diffuse into the products to be treated, or it may be forced into product under pressure in the treatment chamber (Gómez-López et al, 2008;Netramai et al, 2016). Some approaches go further, by placing the reaction location within the generation equipment itself and produce gaseous ClO 2 by use of slow release packages or the addition of acid activators through a vacuum needle (Kingsley et al, 2018;S.-Y.…”