Highlights
► We studied attachment profiles of Escherichia coli K12 and Salmonella Typhimurium P6 on 3 surfaces. ► Presence of residue led to decline in attached cell levels. ► Residue also reduced surface hydrophobicity; cells became difficult to remove. ► Attachment was correlated negatively to the hydrophobicity of surfaces; not with Ra. ► Removal/monitoring of residue on surfaces is essential for safety in transportation.