Glass and stainless steel (StSteel, AISI304-2R), previously cleaned with ethanol (-Eth) or with ethanol and UV-Ozone treatment (-UVO), were soiled with quartz suspensions in water and in a beta-lactoglobulin (beta-LGB) solution, and dried. The cleanability (ease of quartz particle detachment) in water was evaluated using a radial-flow cell. The soiling suspension containing beta-LGB was used as such or after heating for 4 h at 75 degrees C, which provoked coagulation of about 75% of beta-LGB. The substrate-solution interfaces were characterized by X-ray photoelectron spectroscopy (XPS) analysis of conditioned substrates and by contact angle measurements. The substrate surfaces are covered by a layer of organic contaminants which are not removed by pre-cleaning or are adsorbed from the surroundings. The presence of beta-LGB in the soiling suspension leads to protein adsorption, but a significant amount of contaminants remains at the surface. For three of the substrates tested (Glass-Eth, Glass-UVO, StSteel-UVO) the increase of cleanability when the soiling suspension contained beta-LGB may be explained by lower capillary forces acting upon drying. Capillary forces are proportional to the liquid surface tension and depend in a less important way on substrate contact angle. However the order of cleanability observed for the substrates soiled with a suspension of quartz particles in water (Glass-Eth congruent to Glass-UVO < StSteel-UVO < StSteel-Eth) and the influence of beta-LGB on the cleanability of StSteel-Eth may not be explained only by computed capillary forces. The contact angle may exert a direct influence on droplet spreading and particle-substrate contact. The organic contaminants present on the surfaces, which are often neglected by supposing model solid surfaces, may have a significant influence on cleanability through physico-chemical processes which remain to be appreciated. (C) 2015 Elsevier Ltd. All rights reserved.