he HS-SPDE of the aroma compounds was carried out employing a 2.5 ml HS-syringe with a polydimethylsiloxane active charcoal (PDMS/AC) coated needle (Chromtech, Germany). The samples were incubated at 60 °C for 15 min under agitation (500 rpm). After incubation, 1 ml of the headspace was sampled at 100 μl/s by moving the syringe plunger up and down five times. The needle was then desorbed and the headspace injected into the GC column at 50 μl/s.