Table 2.
Comparisons between flavour component levels during browning (180 min) and fermentation (72 h) of brown fermented milk (BFM).
| Number | Flavour Component | Browning Stage (180 min) % | Fermentation Stage (72 h) % | RI | Rt (min) |
|---|---|---|---|---|---|
| Alcohols | |||||
| 1 | 1-Hexanol | 2.42 ± 0.12 | 0.23 ± 0.09 | 867 | 14.63 |
| 2 | 1-Octanol | 0.62 ± 0.19 | 0.18 ± 0.08 | 984 | 20.24 |
| 3 | Trans-2-dodecen-1-ol | 2.41 ± 0.21 | - | 1307 | 9.10 |
| 4 | 2-Furanmethanol | 4.70 ± 0.34 | 4.54 ± 0.15 | 862 | 23.86 |
| 5 | 1-Dodecanol | 0.64 ± 0.07 | - | 1277 | 19.03 |
| 6 | Tridecyl alcohol | 2.01 ± 0.04 | 2.14 ± 0.18 | 1140 | 19.86 |
| 7 | 3,7-Dimethyl-2,6-octadiex-1-ol | 0.23 ± 0.06 | - | 987 | 10.82 |
| 8 | (2,5-Dimethyl-3-furyl) methanol | 0.20 ± 0.02 | 0.13 ± 0.02 | 1735 | 7.38 |
| 9 | 1-Nonanol | - | 0.82 ± 0.17 | 1171 | 16.85 |
| 10 | Cyclopropyl carbinol | - | 0.64 ± 0.09 | 859 | 11.48 |
| 11 | 1-Undecylalcohol | - | 0.20 ± 0.05 | 1329 | 17.36 |
| 12 | Decylalcohol | - | 0.69 ± 0.06 | 1259 | 18.94 |
| 13 | 5-Decen-1-ol | - | 0.31 ± 0.02 | 1139 | 19.34 |
| 14 | 1-Cyclododecanol | - | 0.20 ± 0.03 | 1027 | 21.29 |
| 15 | 1-Hexadecanol | - | 0.97 ± 0.12 | 1530 | 20.54 |
| Carboxylic acids | |||||
| 16 | Phthalic acid | 16.6 ± 0.68 | 1.88 ± 0.24 | 2719 | 29.47 |
| 17 | Hexanoic acid | 4.17 ± 0.44 | 5.28 ± 0.05 | 1946 | 28.99 |
| 18 | Butanoic acid | 23.46 ± 1.14 | 27.19 ± 0.32 | 801 | 23.10 |
| 19 | Octanoic acid | - | 5.73 ± 0.85 | 2189 | 34.23 |
| 20 | Acetic acid | - | 22.17 ± 1.06 | 1463 | 15.79 |
| 21 | Benzoic acid | - | 4.21 ± 0.79 | 2589 | 18.93 |
| 22 | Propionic acid | 0.72 ± 0.15 | - | 1595 | 16.48 |
| 23 | n-Decanoic acid | - | 1.76 ± 0.24 | 1349 | 40.12. |
| Aldehydes | |||||
| 24 | Tridecanal | 5.52 ± 0.82 | 1.18 ± 0.13 | 1103 | 44.12 |
| 25 | Acetaldehyde | 4.12 ± 0.24 | 3.13 ± 0.05 | 707 | 1.42 |
| 26 | Octanal | 1.60 ± 0.28 | - | 1292 | 28.34 |
| 27 | Furfural | 1.65 ± 0.08 | 1.05 ± 0.18 | 834 | 17.83 |
| 28 | 1-Nonanal | 3.22 ± 0.39 | - | 1091 | 35.30 |
| 29 | Benzaldehyde | 2.84 ± 0.33 | - | 964 | 14.92 |
| Ketones | |||||
| 30 | Acetone | - | 2.31 ± 0.12 | 812 | 6.91 |
| 31 | 5-Undecanone | - | 0.21 ± 0.12 | 1597 | 43.66 |
| 32 | 2-Tridecanone | 0.99 ± 0.19 | 0.31 ± 0.05 | 1423 | 38.23 |
| 33 | Nonanone | 0.98 ± 0.13 | 0.13 ± 0.01 | 1389 | 15.45 |
| 34 | 2-Pentadecanone | 2.75 ± 0.37 | 0.24 ± 0.04 | 2022 | 41.23 |
| 35 | 2H-Pyran-2-one | 2.71 ± 0.15 | 2.12 ± 0.02 | 1306 | 32.49 |
| 36 | Nonalactone | 0.82 ± 0.19 | 0.3 ± 0.08 | 1507 | 37.12 |
| 37 | 6-Methyl-5-hepten-2-one | 0.8 ± 0.22 | - | 845 | 22.34 |
| Others | |||||
| 38 | 2-[2-(2-methoxyethoxy)ethoxy]-2-methylpropane | - | 0.34 ± 0.09 | 1458 | 7.96 |
| 39 | 4-Dodecanolide | 0.63 ± 0.15 | - | 1302 | 15.68 |
| 40 | Dibutylphthalate | 2.82 ± 0.42 | 0.26 ± 0.06 | 2107 | 36.59 |
| 41 | Dodecane | 1.05 ± 0.30 | 0.11 ± 0.02 | 1200 | 14.58 |
All compounds were identified using MS and RI; MS: identification based on the NIST MS library; RI: identification based on retention index. Data are presented as mean values ± SDs from three independent experiments. Percentage of flavour component is based on the area normalisation. “-”, not detected.