Electropolishing for the Food & Beverage Industries
Reduce Bacteria Buildup
Over the years, the food and beverage industries have spent a lot of time and money testing varying surface finishing treatments on stainless steel to determine the most beneficial for their applications. The biggest concern is buildup of bacterial biofilms and how to prevent it from occurring. In one test conducted by the poultry and meat processing industry, various surface finishing treatments were tested for their resistance to bacterial attachment. The finishes tested were, electropolishing, mechanical polishing, grinding and sand blasting. It was determined that the electropolishing worked the best in reducing the buildup of bacteria. When the bacteria accumulate, they become increasingly difficult to remove through normal chemical washing. The smooth, electropolished surface finish improved their ability to keep the processing equipment free of contaminates such as Salmonella. The testing results were good news because it offered a way to prevent potentially devastating contamination with reduced use of chemicals and their environmental impact.
Long History with Food and Beverage Applications
Able Electropolishing has worked with the food and beverage industries since its inception in 1954. Prior to realizing the full benefits of electropolishing, a lot of the early applications were for decorative purposes. As more testing was performed, the industries became familiar with the fact that electropolishing offered much more than a decorative finish.
Many of our customers send us welded wire racks that are used in various applications from meat processing to commercial ovens. The electropolishing brightens and cleans the wire, removes the discoloration in the heat affected zones (HAZ) and greatly improves corrosion resistance. When stainless steel is welded, the heat applied to the material creates a condition known as carbide precipitation. In addition to changing the grain structure of the weldment, this condition also lowers the resistance to corrosion.
Electropolishing is specified by manufacturers of soft drinks and beer for parts that come in contact with their products. We currently electropolish a liner and cup rest made from 304 SS that are assembled on a machine for mixing and dispensing soft drinks. Since the machine is used in restaurants for self-service, the manufacturer wanted to make sure that the surfaces that are exposed to the consumer were finished properly. The electropolishing achieves a bright, smooth finish that resists product adhesion. As a result, the sticky soda can be easily removed with household cleaners and the bright electropolished finish will remain indefinitely after continuous cleaning.
Through the years, Able has electropolished thousands of deep drawn products such as trays, pots and tanks used in restaurant food service applications. One particular application involved a 304 SS drawn pan that was used for a steam table in a restaurant. Our customer was currently bead blasting to remove staining from the annealing operation used when drawing the part. They were looking for a process to replace the bead blasting that would remove the stains from annealing and create a clean appearance. In addition, due to the corrosive environment of steam and hot water they wanted to improve the corrosion resistance. Based on our recommendation, our customer sent samples that we electropolished for evaluation and testing. After seeing the improved aesthetics and performing corrosion testing, they were convinced that the electropolishing would be a good fit for their application.
