  We study a model of quark-gluon plasma of 2+1 flavors Quantum Chromodynamics
in terms of quasiparticles propagating in a condensate of Polyakov loops. The
Polyakov loop is coupled to quasiparticles by means of a gas-like effective
potential. This study is useful to identify the effective degrees of freedom
propagating in the medium above the critical temperature. Our finding is that a
dominant part of the phase transition dynamics is accounted for by the Polyakov
loop, hence the thermodynamics can be described without the need for rapidly
increasing quasiparticle masses as $T \rightarrow T_c$, at variance respect to
standard quasiparticle models.
