[en] A phenomenological equation of state of strongly interacting matter, including strange degrees of freedom is presented. It is shown that the hyperon and kaon interactions must be included, in order to obtain a reasonable description of the deconfinement transition at high baryon densities. The consequences of kaon condensation on the nuclear matter - quark matter phase diagram are explored. The relative particle abundances obtained in an isentropic expansion of a blob of quark-gluon plasma are presented for different initial conditions. Implications for ultra-relativistic heavy-ion collisions are briefly discussed. (orig.)