Download or read book Improvement of the Cleanability and Disinfection of Stainless Steel Surfaces for the Food Industry (dairy and Meat) written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In the food and catering industry, cleanability and innocuousness are decisive arguments in choosing stainless steel. All studies dealing with stainless steel cleanability raise the question of why stainless steel is easier to clean than others materials. Industrial cold rolled stainless (1 mm thick) were here investigated in terms of surface chemistry, cleanability, metal release, and corrosion resistance. As far as the surface properties are concerned, the passive film structure is different on new and aged surfaces. Our experimental results strengthen the innucuousness of industriual stainless steels for food industry applications. There, the cleaning process based on soda, nitric acid and alkaline detersives does not introduce important changes on the pitting corrosion resistance. The steel surface reactivity in foodstuffs and cleaning products is directly controlled by the bulk metal composition and the passive film structure, ensuring the properties of innucuousness, corrosion resistance and cleanability. In this work, we have clearly established a new cleaning mechanism. The cleanability mechanism can be considered as a surface peeling on stainless steels. The external layer of the passive film, which is mainly composed of iron oxyhydroxides, is gradually dissolved by the alkaline detersive. This helps the soiling removal. Moreover, electropolishing does not enhance the cleanability of flat sheets. Finally, a low surface free energy material (hydrophobic) is not favourable for cleaning as the detergency principle is no longer respected. The material surface is not complete wetted by the detersive. In this case, the cleaning and desinfecting are no longer ensured.