Display omitted ► Preparation of Au and Au–Cu TiO2 supported catalysts from pre-formed nanoparticles. ► Cu presence allowed a remarkable increase of the catalytic behavior. ► Stability of Au–Cu catalysts was much higher than that shown by the Au material. 5-Hydroxymethyl-2-furfural (HMF) oxidation to furandicarboxylic acid (FDCA) was performed under mild reaction conditions using TiO2-supported Au and Au–Cu catalysts synthesized from pre-formed nanoparticles of different composition. Catalysts were characterized by BET, XRD and XPS. The Au3Cu1/TiO2 catalyst exhibited the best catalytic performance for FDCA yield. Moreover, after reaction, bimetallic Au–Cu catalysts with high gold content can be recovered by filtration and reused without significant loss of activity and selectivity; whereas, the monometallic gold materials are not stable.