Table 2.
MS/MS fragmentation of potential markers of coffee roasting process in negative ionization mode.
| VIP Values | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| # | RT (min) |
Molecular Formula | Tentative Identification | [M−H]− | Mass Error (ppm) | Main MS/MS Fragments | GCB vs. LRC | GCB vs. MRC | GCB vs. DRC | Roasting Trend |
| 1 | 2.2 | C10H10O4 | Hydroxycinnamic acid methyl ester derivative | 193.0483 | 11 | 65.0388 121.0280 93.0334 133.0277 |
0.78670 | 1.12365 | 1.49312 | ↑ |
| 2 | 2.5 | C16H16O8 | Caffeoylshikimic acid isomer | 335.0708 | 11 | 161.0238 135.0440 179.0333 |
1.81873 | 2.19334 | 2.41682 | ↓ |
| 3 | 2.7 | C28H38N8O5 | Hordatine A1 | 565.2902 | 11 | 59.0136 101.0589 113.0234 |
1.82774 | 2.19590 | 1.86040 | ↓ |
| 4 | 13.2 | C34H48N8O10 | Hordatine A1 hexose isomer | 727.3413 | 16 | 643.2944 113.0236 |
0.81788 | 0.95373 | 0.94533 | ↓ |
| 5 | 14.9 | Unknown | 481.2371 | 59.0133 89.0235 |
2.41084 | 2.85921 | 3.12239 | ↓ | ||
| 6 | 14.9 | C34H48N8O10 | Hordatine A1 hexose isomer | 727.3413 | 16 | 643.2942 113.0235 89.0235 |
2.32700 | 2.67836 | 2.78861 | ↓ |
| 7 | 16.4 | C27H38O12 | Ssioriside | 553.2225 | 3 | 44.9983 89.0239 59.0143 391.0400 119.0358 |
1.54553 | 2.49650 | 2.52013 | - |
| 8 | 17.7 | Unknown | 135.0436 | 67.0185 | 1.38856 | 1.31171 | 0.51246 | ↓ | ||
| 9 | 18.5 | Unknown | 135.0448 | 134.0358 89.0381 |
1.75153 | 1.26031 | 1.05637 | ↓ | ||
| 10 | 18.6 | C16H18O9 | Neochlorogenic acid * | 353.0803 | 7 | 191.0553 179.0339 135.0439 |
2.04079 | 1.59240 | 0.56977 | ↓ |
| 11 | 21.6 | Unknown | 705.3292 | 659.3259 335.2215 323.0965 |
1.80217 | 9.9 × 10−9 | 9.7 × 10−9 | ↑ | ||
| 12 | 25.1 | Unknown | 341.0528 | 89.0242 59.0138 71.0137 |
1.98371 | 2.6 × 10−8 | 2.2 × 10−8 | ↑ | ||
| 13 | 29.0 | Unknown | 242.0787 | 78.9588 168.0424 |
0.82795 | 0.43160 | 1.35421 | ↓ | ||
# Metabolite number. * Confirmed with standard ↑ The level of the compound increases with roasting. ↓ The level of the compound decreases with roasting.