Table 2.
Volatile chemical composition of FROs.
| Content (μg/g) | OAV | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Name | RI | Threshold | Control | Market | Pro | Lys | Glu | Arg | Control | Market | Pro | Lys | Glu | Arg | |
| 1 | 2-Ethyl pyrazine | 930 | 0.25 | 2.05 | 1.88 | / | 1.27 | / | 1.69 | 8.20 | 7.52 | <1 | 5.08 | <1 | 6.76 |
| 2 | Pentanal | 935 | 0.05 | 2.43 | / | / | / | 4.78 | 2.12 | 48.60 | <1 | <1 | <1 | 95.60 | 42.40 |
| 3 | Hexanal | 1083 | 0.07 | 2.17 | 1.28 | 1.82 | 1.45 | 1.90 | 1.98 | 31.00 | 18.29 | 26.00 | 20.71 | 27.14 | 28.29 |
| 4 | Heptanal | 1174 | 0.05 | 2.79 | / | 3.12 | / | / | 4.53 | 55.80 | <1 | 62.40 | <1 | <1 | 90.60 |
| 5 | Furan, 2-pentyl- | 1231 | 0.10 | 1.38 | 0.46 | 1.55 | / | 1.76 | / | 13.80 | 4.60 | 15.50 | <1 | 17.60 | <1 |
| 6 | (E)-2-Heptenal | 1243 | 0.04 | / | 2.07 | / | 2.60 | 2.70 | / | <1 | 51.75 | <1 | 65.00 | 67.50 | <1 |
| 7 | Pyrazine, 2-methyl | 1266 | 6.00 | 2.30 | 2.87 | 2.47 | 7.57 | 4.92 | 2.89 | <1 | <1 | <1 | 1.26 | <1 | <1 |
| 8 | 2,5-Dimethyl--pyrazine | 1320 | 2.00 | 3.82 | 4.01 | 4.28 | 4.65 | 3.90 | 3.90 | 1.91 | 2.01 | 2.14 | 2.33 | 1.95 | 1.95 |
| 9 | 2,6-Dimethylpyrazine | 1328 | 0.40 | 2.74 | 3.34 | 2.14 | 2.55 | / | 2.25 | 6.85 | 8.35 | 5.35 | 6.38 | <1 | 5.63 |
| 10 | 2-ethyl-5-methylpyrazine | 1341 | 0.02 | 1.03 | 3.41 | 5.40 | / | 4.98 | 1.98 | 51.50 | 170.50 | 270.00 | <1 | 249.00 | 99.00 |
| 11 | (E)-2-Octenal | 1345 | 0.006 | 3.10 | 2.21 | 2.05 | 1.81 | / | 0.71 | 775.00 | 552.50 | 512.50 | 452.50 | <1 | 177.50 |
| 12 | 1-Hexanol | 1360 | 0.45 | 1.45 | 2.72 | 3.08 | 3.11 | 2.85 | 2.67 | 3.22 | 6.04 | 6.84 | 6.91 | 6.33 | 5.93 |
| 13 | 2-ethyl-6-methylpyrazine | 1386 | 0.04 | 2.25 | 3.58 | 5.46 | 2.82 | 4.81 | 3.33 | 56.25 | 89.50 | 136.50 | 70.50 | 120.25 | 83.25 |
| 14 | Nonanal | 1391 | 0.26 | 3.17 | 2.27 | 2.00 | 1.19 | 2.42 | 2.82 | 12.19 | 8.73 | 7.69 | 4.58 | 9.31 | 10.85 |
| 15 | Trimethylpyrazine | 1406 | 0.29 | 0.95 | 3.43 | / | 3.53 | 2.12 | 1.14 | 3.28 | 11.83 | <1 | 12.17 | 7.31 | 3.93 |
| 16 | Acetic acid | 1452 | 0.50 | 1.50 | 1.19 | 1.49 | 0.99 | 1.48 | 1.30 | 3.00 | 2.38 | 2.98 | 1.98 | 2.96 | 2.60 |
| 17 | Furfural | 1461 | 3.00 | 3.19 | 4.69 | 4.11 | 4.58 | 3.74 | 4.01 | 1.06 | 1.56 | 1.37 | 1.53 | 1.25 | 1.34 |
| 18 | 3-Ethyl-2,5-dimethylpyrazine | 1464 | 0.08 | 0.97 | 0.74 | 2.80 | 1.63 | 2.12 | 0.57 | 12.13 | 9.25 | 35.00 | 20.38 | 26.50 | 7.13 |
| 19 | 2-Acetylfuran | 1501 | 1.00 | 0.18 | 0.92 | 1.23 | 1.97 | 1.20 | 1.14 | <1 | <1 | 1.23 | 1.97 | 1.20 | 1.14 |
| 20 | Benzaldehyde | 1508 | 0.06 | 1.57 | 2.43 | 2.29 | 5.62 | 2.12 | 2.01 | 26.17 | 40.50 | 38.17 | 93.67 | 35.33 | 33.50 |
| 21 | Furaneol | 1669 | 5.00 | 2.25 | / | 1.31 | 0.60 | 1.42 | 2.02 | <1 | <1 | <1 | <1 | <1 | <1 |
| 22 | 2(5H)-Furanone | 1767 | 0.04 | 0.91 | 1.85 | 3.42 | 4.27 | 2.32 | 1.44 | 22.75 | 46.25 | 85.50 | 106.75 | 58.00 | 36.00 |
| 23 | Benzenepropanenitrile | 2041 | 0.02 | 2.40 | 3.22 | 0.97 | 2.21 | 1.63 | 0.60 | 120.00 | 161.00 | 48.50 | 110.50 | 81.50 | 30.00 |
Note: “/” is not detect.