Jan 01, 2021 · SPME headspace vials (20 mL screw neck, vial ND18 clear 75,5 × 22,5 mm round bottom, SU860097) and silicone/ Polytetrafluoroethylene (PTFE) screw caps (SU860101) were purchased from Bellefonte, PA, USA). SPME liner (2637501) was purchased from SUPELCO (Bellefonte, PA, USA). 2.2. Sample collection