The use of atomic force microscopy to measure the efficacies of various chemical sanitizers in removing organic matter from glass surfaces

Improper washing and sanitizing of tableware items is a significant public health risk. Residual food soils left on food-contact surfaces can harbor pathogenic microorganisms and may even allow them to form biofilms. This study investigated the effect of various sanitizers (sodium hypochlorite, quaternary ammonium compound, neutral electrolyzed water and an acidic formulation) for removal of various milk-based products (whole, 2% reduced fat, chocolate low-fat and skim milk) from underlining glass surfaces. Atomic force microscopy (AFM) was used to determine the thicknesses of the milk films left after attempts to clean the glass surfaces. Results showed that PRO-SAN® (the acidic formulation) significantly reduced the amount of residual food soil when compared with the other sanitizers. This could be due to sodium dodecylbenzene sulfonate (a surfactant) being present in the acidic formulation. The data also showed that whole and chocolate milk would be more difficult to clean when compared with 2% and skim milk.