Akademska digitalna zbirka SLovenije - logo
E-viri
Celotno besedilo
Recenzirano
  • Possible explanation for li...
    Işık, Sefa; Aytemiş, Zeynep; Çetin, Bülent; Topalcengiz, Zeynal

    Journal of food safety, August 2022, 2022-08-00, 20220801, Letnik: 42, Številka: 4
    Journal Article

    The purpose of this study was to determine the efficacy of spray application of chlorinated water before harvest on the population of Salmonella enterica Typhimurium and Escherichia coli O157:H7 on radish microgreens. The transfer of abiotic surrogate to radish microgreens was also evaluated to track possible pathogen contamination spread by inoculating seed and growth media. During growth, microgreens inoculated with strains of pathogens were sprayed with chlorinated water at three different concentrations (0.50, 1.00, and 2.00 ± 0.05 ppm free chlorine). Spray application of chlorinated water was performed on microgreens once (day 9), twice (day 8 and 9), three (day 7, 8, and 9), and four times (day 6, 7, 8, and 9). Microgreens were harvested 12 hr after the last application of chlorinated water. Salmonella and E. coli O157:H7 populations were reduced with the increase in chlorine concentration. Chlorinated water reduced Salmonella and E. coli O157:H7 populations up to 1.1 log CFU/g (p < .05) and 0.9 log CFU/g (p > .05), respectively. Images taken under UV illumination provided the visualization of abiotic surrogate spread on cotyledon and upper hypocotyl (all edible parts) of radish microgreen plants regardless of seed or growth media inoculation. Scanning Electron Microscopy showed the presence of abiotic surrogate and generic E. coli on microgreen leaves. Spray application of chlorinated water during microgreen growth may help to reduce microbial load but cannot be used as the only control measure. Pre‐harvest factors as contaminated irrigation water and growth media may cause transfer of pathogens on microgreens. Post‐harvest treatments of microgreens to reduce pathogen populations are not preferred due to fragile structure of immature seedlings. This study demonstrates the potential use of chlorinated water before harvest to reduce population of pathogens while eliminating adverse effect of post‐harvest safety treatments. However, this study also shows that spray application of chlorinated water before harvest cannot be used as only control measure due to vast contamination spread of microorganisms simulated with abiotic surrogate.