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.
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