For identification of the volatile organic compounds (VOCs) present in the distillates, GC-MS/O was performed using a Trace GC Ultra and a Trace dual stage quadrupole (DSQ) mass spectrometer (both Thermo Fisher Scientific GmbH) equipped with a DB-FFAP column (30 m × 0.32 mm, 0.25 μm film thickness, J&W Scientific, Waldbronn, Germany). Measurements were performed following the method described in detail by Bickel Haase et al. (2021) (link). Samples were evaluated by three trained panellists.
Further GC-MS/O determinations were performed using an Agilent GC-MSD (Agilent Technologies, Waldbronn DE). Aliquots (2 μL) of the samples were injected in pulsed splitless mode at 250 °C by means of an autosampler PAL RSI 85 (CTC Analytics AG, Zwingen, Switzerland). At the end of the column (DB-FFAP, 30 m × 0.25 mm, 0.25 μm film thickness, J&W Scientific), the effluent was split 1:1 by a Y-splitter. Two deactivated fused silica capillaries led either to an odor detection port (235 °C) or a mass spectrometer. The oven temperature was 40 °C at the beginning, raised at 6.0 °C/min after 2 min to 235 °C, and held for 5 min. The flow rate of the helium carrier gas was 2.0 mL/min in constant flow. Mass spectra were generated in the positive electron impact (EI) ionization mode at 70 eV (Scan 35–400 m/z).
Further GC-MS/O determinations were performed using an Agilent GC-MSD (Agilent Technologies, Waldbronn DE). Aliquots (2 μL) of the samples were injected in pulsed splitless mode at 250 °C by means of an autosampler PAL RSI 85 (CTC Analytics AG, Zwingen, Switzerland). At the end of the column (DB-FFAP, 30 m × 0.25 mm, 0.25 μm film thickness, J&W Scientific), the effluent was split 1:1 by a Y-splitter. Two deactivated fused silica capillaries led either to an odor detection port (235 °C) or a mass spectrometer. The oven temperature was 40 °C at the beginning, raised at 6.0 °C/min after 2 min to 235 °C, and held for 5 min. The flow rate of the helium carrier gas was 2.0 mL/min in constant flow. Mass spectra were generated in the positive electron impact (EI) ionization mode at 70 eV (Scan 35–400 m/z).