Abstract We study various non-equilibrium properties of a mixture comprised of pions, kaons and nucleons. The concentration of the constituents is chosen to mimic those expected in the mid-rapidity interval of CERN and RHIC experiments. The heavier kaons and nucleons are found to equilibrate more slowly than pions. These results shed new light on the influence of collective flow effects on the transverse momentum distributions of kaons and nucleons versus those of pions in ultrarelativistic nuclear collisions.