Quantitative analysis of survival of Staphylococcus aureus or Listeria innocua on two types of surfaces: Polypropylene and stainless steel in contact with three different dairy products

The survival of Listeria innocua and Staphylococcus aureus on two types of surface: polypropylene and stainless steel were investigated after contamination with milk products. Sheets were incubated at 12 °C or 25 °C during 8 days. The survival and growth of the two strains were possible but different according to milk origins, temperature and surface. L. innocua attached to stainless steel in cheese curd reached approximately 3.6 ± 0.2 Log CFU cm−2 at 12 °C but was not detected at 25 °C after 8 days. The result was different on polypropylene with 3.0 ± 0.5 Log CFU cm−2 in cheese curd at 25 °C. S. aureus growth is more limited by cheese curd than L. innocua on the two surfaces at the two temperatures tested.