Surface modification to reduce dairy fouling

Abstract

Surface modification, for example through the application of a surface coating, potentially provides a solution to mitigate fouling and/or improve cleaning in a number of industrial applications. Such surface modification may alter one or more surface properties including surface roughness, surface free energy, wettability and surface charge. It is expected that altering these surface properties may influence the deposit adhesion and fouling deposition behaviour. The literature suggests that lowering of surface energy promotes reduction in fouling deposits. However conflicting results have been reported for hydrophobic surfaces. This study aims to investigate and clarify this apparent contradiction through the assessment of fouling on modified surfaces for use in the dairy industry. Stainless steel surfaces were modified by the deposition of doped Diamond-like Carbon Films (DLC). The fouling behaviour of the coated surfaces in contact with milk was investigated using a laboratory scale Flow Tube and Disk Fouling Rig. All modified surfaces were observed to result in about 15 % less in fouling deposit weight in comparison with the non-coated surface.