Table 2.
Rel. abundance TD [%]c | Rel. abundance SPME [%]c | ||||||||
---|---|---|---|---|---|---|---|---|---|
Peak label | Compound | Level of confidencea | Chemical formula | Key ions (m/z) | RTb | 150 °C | 250 °C | Median | SD |
CO2 | Carbon dioxide | 2 | CO2 | 44 | 9.27* | High | High | ||
H2S | Hydrogen sulfide | 2 | H2S | 34 | 12.09* | High | High | ||
COS | Carbonyl sulfide | 2 | COS | 60 | 11.51 | 24.48 | 4.56 | 4.59 | 1.41 |
H2O | Water | 2 | H2O | 18 | 12.93* | High | High | high | 0,00 |
SO2 | Sulfur dioxide | 2 | SO2 | 48, 64 | 15.51 | 14.31 | |||
Ea | Ethanal | 2 | C2H4O | 44 | 15.58 | 1.40 | 1.91 | 1.75 | |
MT | Methanethiol | 2 | CH4S | 48 | 15.70 | 7.80 | 5.04 | 3.97 | 0.46 |
Bu | But-1-ene | 1 | C4H8 | 56 | 16.21 | tr | 1.84 | tr | |
Eo | Ethanol | 3 | C2H6O | 45 | 17.26 | tr | tr | ||
Pa | Prop-2-enal | 2 | C3H4O | 56 | 17.55 | 0.35 | 0.33 | 0.00 | |
CS2 | Methanedithione | 2 | CS2 | 76 | 17.63 | 43.20 | 45.80 | 9.08 | 1.63 |
Pa' | Propanal | 3 | C3H6O | 58 | 17.68 | 0.35 | 0.54 | 0.42 | |
ET | Ethanethiol | 2 | C2H6S | 29, 47, 62 | 17.70 | tr | 0.43 | 0.69 | 0.27 |
MSM | (Methylsulfanyl)methane | 2 | C2H6S | 47, 62 | 17.79 | tr | 0.13 | 1.56 | 0.49 |
Po | Propan-2-one | 2 | C3H6O | 43, 58 | 17.84 | 3.89 | 1.87 | 7.28 | 2.48 |
Ba | But-2-enal | 3 | C4H6O | 70 | 18.46 | 0.64 | 0.87 | 0.00 | |
Ox | Oxolaned | 2 | C4H8O | 72 | 19.27 | tr | 11.28 | 4.71 | 3.64 |
Bo | Butan-2-one | 3 | C4H8O | 72 | 19.38 | tr | 3.06 | 1.23 | |
Hex | n-Hexane (RT standard) | C6H14 | 19.68 | ||||||
TP | Thiophene | 2 | C4H4S | 84 | 19.89 | tr | 0.64 | 0.53 | 0.04 |
B | Benzene | 2 | C6H6 | 78 | 19.97 | 0.38 | 0.52 | 0.33 | |
Ac | Acetic acid | 3 | C2H4O2 | 60 | 20.10 | 20.63 | 8.89 | 1.71 | 0.29 |
MB | 3-methylbutan-2-one | 3 | C5H10O | 86 | 20.44 | 0.69 | 0.00 | ||
Mxp | 1-Methoxypropan-2-ol | 3 | C4H10O2 | 45,47 | 20.72 | 4.01 | 0.00 | ||
Pe | Pentanal | 3 | C5H10O | 44,58 | 20.73 | tr | |||
MDSM | (Methyldisulfanyl)methane | 2 | C2H6S2 | 94 | 20.91 | 7.70 | 3.58 | ||
To | Toluene | 2 | C7H8 | 91 | 21.36 | 4.05 | 1.08 | ||
TL | Thiolane | 2 | C4H8S | 60, 88 | 21.41 | 1.20 | |||
MP | 4-Methylpentan-2-one | 3 | C6H12O | 43, 58, 85 > 100 | 21.63 | 5.23 | 0.90 | ||
Ha | Hexanal | 3 | C6H12O | 56, 82 | 22.17 | 2.53 | 0.15 | ||
MEDS | (Methyldisulfanyl)ethane | 2 | C3H8S2 | 108 | 22.34 | 1.31 | 0.38 | ||
Xy I | p-Xylene | 2 | C8H10 | 91, 106 | 22.91 | tr | |||
Xy II | m-Xylene | 2 | C8H10 | 91, 106 | 22.99 | 1.04 | 0.32 | ||
Pac | 1-Methoxyprop-2-yl acetate | 1 | C6H12O3 | 72, 87 | 23.19 | 1.15 | 0.06 | ||
Xy III | o-Xylene | 2 | C8H10 | 91, 106 | 23.37 | tr | |||
Sty | Styrene | 1 | C8H8 | 91, 104 | 23.41 | tr | |||
CH | Cyclohexanone | 3 | C6H10O | 98 | 23.66 | 1.97 | 1.28 | ||
Hp | Heptanal | 3 | C7H14O | 55, 70 | 24.27 | 1.09 | 0.07 | ||
BA | Benzaldehyde | 2 | C7H6O | 77, 106 | 25.09 | 0.89 | 16.23 | 3.78 | |
MTSM | (Methyltrisulfanyl)methane | 2 | C2H6S3 | 126 | 25.18 | 11.44 | 7.07 | ||
TMB I | 1,3,5-Trimethyl benzene | 1 | C9H12 | 105, 120 | 25.23 | tr | |||
TMB II | 1,2,4-Trimethyl benzene | 2 | C9H12 | 105, 120 | 25.35 | tr | |||
MH | 6-Methylheptan-3-one | 1 | C8H16O | 72, 99 | 25.95 | 2.03 | 0.00 | ||
TMB III | 1,2,3-Trimethyl benzene | 2 | C9H12 | 105, 120 | 26.04 | 2.03 | 0.68 |
See also Supplementary Fig. 2 for molecular structures.
RT retention time, TD thermal decrepitation/desorption, SPME solid phase micro extraction, SD standard deviation, tr traces.
aLevel of confidence: 3 = verified by standard, 2 = clear identification with reference spectra, 1 = tentative identification.
bRT marked by asterisks (*) are from TD-GC–MS analysis, other RT from SPME-GC–MS experiments. From 15 min RT in both methods are similar.
cCompounds present in traces (tr) and main components (CO2, H2S, H2O) were not included in relative abundance calculations.
dSmall amounts of oxolane were identified in SPME-GC–MS blanks (see Supplementary Fig. 4).