Purpose: The aim was to evaluate the influence of pre-wash chopping on the S. Typhimurium decontamination by common washing and disinfection methods.
Methods: Vinegar (4%, v/v, acetic acid), 0.25g/l sodium dichloroisocyanurate (NaDCC), and water combined with rinsing and manual agitation were applied for 15 minutes.
Results: This study demonstrated limited efficiency of applied methods and that holding pre-wash chopped leaves at 30ºC reduced the effectiveness of all washing solutions. Scanning electron microscopy (SEM) imaging indicated initiation of biofilm formation after 24 h at 5ºC with noticeable adhesion of cells to inaccessible folds of the vein on the leaf surface. NaDCC was shown to be the most effective solution achieving log reductions of 1.92 - 3.12 on intact parsley leaves. The latter being on those held at 5ºC for 4 h; however, its effectiveness was reduced by 0.73-0.93 and 1.19 log cfu/g on chopped leaves at 5ºC and on both intact and chopped leaves at 30ºC, respectively.
Significance: In conclusion, strict temperature control and avoiding pre-wash chopping are highly recommended during handling of parsley for the optimal elimination of pathogenic microorganisms.