“…Regardless of the species of a medicinal-aromatic plant, its morphological part or purpose, it is indicated that drying of medicinal-aromatic plants, which accumulate non-volatile active substances, is recommended at 50-100°C (Müller, Heindl, 2006). After drying the purple coneflower at a temperature of 40-70°C, it was determined that the higher temperature of drying agent increased losses of phenolic compounds, as well as losses of chicoric acid (Kim et al, 2000;Stuart, Wills, 2003;Lin et al, 2011). Many researchers have analysed various drying methods used for purple coneflower: freeze-drying, vacuum microwave and convection drying (Kim et al, 2000;Stuart, Wills, 2003;Lin et al, 2011).…”