Cleanability and water resistance of surfaces in the food industry

There is so much you can achieve with coated surfaces. They add value to products, making them more competitive. Through a series of cases based on the needs of different sectors, Sirris will give you an idea about their potential. This blog post will look in more detail at the possibilities for production processes in the food industry. 

In addition to the manufacturing industry another particularly large sector also benefits greatly from the use of advanced surface functionalities: the food processing industry and producers of packaging for this sector (see previous blog) . Easy-to-clean surfaces are of primary importance in the food processing industry. Keeping equipment clean during the production process is a constant challenge. Control of all sources of contamination requires a major effort to ensure food quality and safety. Mineral products such as CaCO3, organic soils and microbiological contaminants are harmful to equipment and can often only be removed when the production is interrupted. Cleaning accounts for 15 percent of the total production time in the dairy industry. Coatings or surface treatments that facilitate cleanability can be a valuable part of a hygiene plan in a food factory.

Production process

In the food processing industry, the surfaces are mainly made of stainless steel (CRES). A typical finish of the surfaces is the staining and passivation or wet blasting of those surfaces. Surface treatments such as electropolishing or amorphising can already make surfaces more resistant to dirt and easier to clean without the need to apply a coating. What actually happens here is that the surface is very smooth, so dirt and bacteria can not easily adhere to form a biofilm. In addition to a smooth surface, coatings could also play an important role here in achieving an easy-to-clean effect. There are basically three main groups of coatings that can be considered: ceramic PVD coating, inorganic (silicium-based) coatings and fluoropolymer coatings. Which type of coating is used depends on many different factors, including abrasion resistance, chemical resistance, dimensions and complexity of the component and process temperature.

Although there are many easy-to-clean coatings on the market, they are not yet widely used in the food industry. One of the most important reasons is that the coatings must, of course, be Food Approved before they can be applied. On the other hand, it must also be possible to apply the coating to existing installations and the cost price and life span also play a role in the consideration of using coatings in the production process. Chemical resistance is also an important issue, as thorough cleaning will continue to take place in the food industry.

Two years ago Sirris carried out a benchmark study on the applicability of easy-to-clean coatings for food applications. Ten different commercial easy-to-clean coatings were examined.

Read more about it in the casebook about functional surfaces which we compose for you.

In a next blog we will have a look at the possibilities of coatings and textures in scientific applications. Would you like to stay up-to-date with our series about functional surfaces? Register here!