According to the cosmological big bang model the universe has undergone several phase transitions (GUT, Electroweak, quark to hadron etc) at different stages of its evolution. The quark-hadron transition occurred in the universe when it was a few microsecond old and is the only transition which can be accessed in the laboratory. In this phase transition, the chiral condensate is one of the order parameter measuring the breaking of chiral symmetry and its study is important to understand the origin of the mass of hadrons. By applying real-time thermal field theory, investigating the spectral and transport properties of hadrons in medium may be considered as an indirect probe to the condensate as well as the phase transition.