Deposition of two microbial strains encountered in the dairy industry(Leuconostoc mesenteroidesandStreptococcus thermophilus)to substrata with different wettabilities was studied in a parallel plate flow cell. Deposition was studied both from a bacterial suspension in water and in potassium phosphate buffer (pH 70).L. mesenteroidesadhered rather weakly and showed no clear preference for any of the substrata. Conversely,S. thermophilusadhered much better to substrata with a high wettability than to low wettability substrata. Using real‐time image analysis, it was observed that after an initially high deposition of S.thermophilusfrom water to glass, cells subsequently desorbed leaving a biosurfactant layer on the surface to which freshly cultured cells did not adhere. Presumably this layer is due to biosurfactants produced by the adhering cells themselves. Such a biological anti‐adhesive coating might have great potential for the control of microbial fouling in dairy processing.