Table 2.
Comparison of previously tentatively identified PTR-MS signals6 to the results obtained in this study using GC–MS and the fragmentation pattern analysis of the PTR-MS signals.
| PTR-MS signal (M + 1) (u) | Tentative identification (PTR-MS)6 | Confirmed signals (this study) |
|---|---|---|
| 35 | Hydrogen sulphide | Hydrogen sulphide (contribution also from 2-methyl-propanethiol and some other fragment ions) |
| 49 | Methanethiol | Methanethiol (contribution also from DMDS and DMTS fragment ions) |
| 57 | Butene, acrolein | Combination of fragment ions from: 3-methyl-2-pentanone, 5-methyl-2-heptanone (agar), 2-methyl-1-propanethiol |
| 59 | Acetone | Acetone, combination of fragment ions: 3-methyl-2-pentanone, 5-methyl-2-heptanone (agar) |
| 63 | DMS | Combination of fragment ions |
| 69 | Isoprene, fragment ion (C5H9+) | Combination of fragment ions from: 3-methylbutanal, 5-methyl-2-heptanone (agar) |
| 71 | Pentene/isopentene, crotonaldehyde | Combination of fragment ions from: isoamyl propionate, ethyl isobutyrate, 3-methyl-1-butanol (agar) |
| 85 | Cyclopentanone | Combination of fragment ions from: 4-methyl-1-pentanol |
| 87 | Pentanone/methyl butanal, diacetyl, methyl butenol | 3-Methyl-1-butanal |
| 91 | Butanethiol, methylthiourea, tropylium ion/other fragment ion (C7H7+) | 2-Methyl-1-propanethiol |
| 95 | DMDS, phenol, fragment ion (C7H11+) | DMDS |
| 101 | Hexanal, acetyl acetone, MIBK | 3-Methyl-2-pentanone, combination of fragment ions from: 5-methyl-2-heptanone (agar), 4-methyl-1-pentanol, methyl metacrylate (agar), methyl isobutyrate |
| 118 | Indole, benzyl cyanide | Indole |