Parameters of treated stainless steel surfaces important for resistance to bacterial contamination
Use of materials that are resistant to bacterial contamination could enhance food safety during processing. 
Common finishing treatments of stainless steel surfaces used for components of poultry processing equipment were tested for 
resistance to bacterial attachment. Surface characteristics were evaluated to determine factors important for resistance. 
Disks of stainless steel were steel–ball burnished, glass–beaded, electropolished, acid–dipped, sandblasted, or left untreated. 
After treatment, the disks were incubated with bacteria from chicken carcass rinses. Bacterial growth during surface exposure 
was monitored by spectrophotometry, and bacterial counts were measured by scanning electron microscopy (SEM). The 
morphology of the surfaces was analyzed by atomic force microscopy (AFM), using disks from each of the treatments in the 
SEM studies. Changes in root mean square (RMS) roughness, center line average, bearing ratio/area, and other measurements 
corresponded to changes in bacterial contamination. Electropolished stainless steel showed fewer bacteria and biofilm 
formations than the other surfaces. The elemental composition of the surface was not changed by electropolishing. This article 
is the first to show that AFM is a rapid method for predicting the potential resistance of a surface to bacterial contamination. 
These results will aid manufacturers and processors in comparing and selecting finishes that are cost–effective and resistant 
to contamination.