Mechanical abrasion with subsequent spray applications of sanitizer as a method to remove biofilms and non-biofilms from food processing surfaces

The attachment and potential growth of bacteria remaining on food processing equipment after sanitation can cause cross-contamination, which can lead to food spoilage and possible food safety concerns. The purpose of this research was to experimentally determine, as compared to conventional hydraulic spray, if air-assisted, induction-charged electrostatic sprays of sanitizers would provide a more effective means of sanitizing food contact surfaces to reduce bacterial attachment of biofilms. Initially, stainless steel, PVC and waxed cardboard were inoculated with Salmonella, Listeria monocytogenes or Escherichia coli O157:H7 and subjected to air-assisted, induction-charged electrostatic spray or hydraulic spray applications using surfactant or sanitizer. This study found that spray applications alone were not effective in removing biofilms. Further studies used mechanical abrasion with subsequent spray applications of sanitizer to reduce biofilm and non-biofilm populations of L. monocytogenes from stainless steel surfaces and showed significant reductions attributable to the techniques employed and revealed the necessity of abrasion to remove biofilms and adherent cells from stainless steel surfaces.