A contaminant-free surface is a critical requirement of the food processing sector and electropolishing is a highly effective way to achieve the level of surface smoothness required for keeping stainless steel components scrupulously clean.
Pillsbury Australia in Melbourne's outer east is one of a growing number of food processors who have opted for electropolishing for hygienic and durable stainless steel components. Pillsbury produces the fresh pasta brand Latina Fresh. The range consists of filled pasta types like ravioli and tortellini for which the fillings are cooked during manufacture, but the consumer completes the cooking process at home. For some years now, Pillsbury has specified an electropolished finish for all its stainless steel food preparation equipment and related components such as trolleys, cooling racks and other fittings. These are manufactured by GP's Fabrications and electropolished by ASSDA member MME Surface Finishing.
As well as promoting hygiene, electropolishing enhances stainless steel's corrosion resistance. Many fittings in Pillsbury's plant have been in constant operation for eight to ten years and show no sign of surface deterioration despite exposure to steam-laden, high temperature atmospheres.
Electropolishing works by selectively removing surface metal thereby smoothing and levelling the stainless steel. This is done by immersing the component in a chemical bath to which lowvoltage electric current is added. Stock removal is controlled to a high degree of accuracy by adjusting the time, temperature and current density.
The resulting finish is free of surface flaws and impurities, giving no opportunities for deposits to lodge and contaminate the food product. A further benefit is that it makes the components easier to keep clean, allowing for longer periods of processing activity.
This article featured in Australian Stainless magazine - Issue 22, September 2002.