Table 4.
Comparison of volatile organic compound content of sesame oil with different treatments and sold sesame oil.
| No. | Chemical Compound | 1 Kis | Content (μm/mL) | 2 Odors | |||||
|---|---|---|---|---|---|---|---|---|---|
| C-SO | PH-SO | GPH-SO | PHM-SO | GPHM-SO | S-SO | ||||
| Pyrazines | |||||||||
| 1 | Methylpyrazine | 781 | 13.48 ± 0.12 c | 24.41 ± 0.13 c | 26.02 ± 0.21 c | 29.98 ± 0.47 b | 32.38 ± 0.29 a | 28.28 ± 0.24 b | chocolate, meaty |
| 2 | 2,5-Dimethylpyrazine | 894 | 3.44 ± 0.08 d | 13.63 ± 0.23 c | 13.52 ± 0.29 c | 16.26 ± 0.65 b | 18.23 ± 0.37 a | 16.56 ± 0.32 b | potato-like |
| 3 | 2,6-Dimethylpyrazine | 894 | 10.79 ± 0.67 e | 11.19 ± 0.89 d | 11.88 ± 0.83 c | 13.41 ± 0.73 b | 15.11 ± 0.85 a | 11.18 ± 0.56 d | roasted, nutty |
| 4 | Ethylpyrazine | 881 | 7.27 ± 0.08 a | 3.77 ± 0.31 d | 4.30 ± 0.16 cd | 4.80 ± 0.46 bc | 5.29 ± 0.08 b | 3.23 ± 0.25 d | peanut buttery |
| 5 | 2,3-Dimethylpyrazine | 894 | 1.50 ± 0.11 c | 2.89 ± 0.26 b | 2.88 ± 0.19 b | 3.64 ± 0.15 ab | 3.86 ± 0.28 a | - | cocoa-like |
| 6 | 2-Ethyl-5-methylpyrazine | 994 | 9.03 ± 0.24 d | 8.80 ± 0.23 d | 8.75 ± 0.53 d | 10.56 ± 0.28 b | 11.74 ± 0.66 a | 9.80 ± 0.33 c | grassy |
| 7 | Trimethyl-pyrazine | 1008 | 8.06 ± 0.32 e | 10.39 ± 0.37 d | 10.49 ± 0.18 d | 12.48 ± 0.58 b | 13.03 ± 0.18 a | 11.29 ± 0.47 c | roasted |
| 8 | 3-Ethyl-2,5-dimethylpyrazine | 1107 | 4.85 ± 0.17 d | 6.33 ± 0.53 c | 6.15 ± 0.09 c | 7.55 ± 0.56 b | 8.41 ± 0.32 a | 7.38 ± 0.64 b | roasted |
| 9 | 2,3-Dimethyl-5-ethylpyrazine | 1102 | - | - | - | - | - | 5.23 ± 0.52 a | roasted, nutty |
| 10 | 2-Ethenyl-6-methylpyrazine | 984 | 0.52 ± 0.02 d | 0.73 ± 0.02 c | 0.72 ± 0.03 c | 1.03 ± 0.04 b | 1.15 ± 0.06 a | - | - |
| 11 | 2-Acetyl-3-methylpyrazine | 1130 | 5.78 ± 0.14 a | 3.49 ± 0.27 d | 3.34 ± 0.47 d | 4.04 ± 0.28 c | 4.56 ± 0.25 b | 4.23 ± 0.41 bc | grain-roasted |
| Furans | |||||||||
| 12 | 2-Pentyl-furan | 1040 | 0.15 ± 0.02 c | 0.11 ± 0.01 d | 0.30 ± 0.02 a | 0.31 ± 0.03 a | 0.27 ± 0.01 b | 0.25 ± 0.01 b | fruity |
| 13 | 1-(2-Furanyl)-ethanone | 878 | 1.75 ± 0.08 b | 1.49 ± 0.29 cd | 1.55 ± 0.08 c | 1.78 ± 0.09 b | 1.92 ± 0.09 a | 1.45 ± 0.16 d | coffee aroma |
| 14 | 2-Furanmethanol, acetate | 1009 | 0.46 ± 0.01 d | 0.56 ± 0.04 c | 0.58 ± 0.04 c | 0.63 ± 0.06 b | 0.72 ± 0.05 a | - | - |
| 15 | 2-Furanmethanol | 885 | 1.32 ± 0.06 d | 2.54 ± 0.08 c | 2.51 ± 0.05 c | 2.99 ± 0.12 b | 3.42 ± 0.14 a | 2.58 ± 0.21 c | cooked sugar |
| 16 | 2-Acetylfuran | 925 | - | - | - | - | - | 1.65 ± 0.12 a | sweet, popcorn |
| 17 | 5-Methyl-2-furancarboxaldehyde | 920 | 5.28 ± 0.14 c | 5.44 ± 0.28 c | 5.43 ± 0.29 c | 6.42 ± 0.42 b | 7.09 ± 0.18 a | 5.68 ± 0.24 c | caramel-like |
| 18 | 2-Acetyl-5-methylfuran | 967 | 0.33 ± 0.02 c | 0.34 ± 0.02 c | 0.34 ± 0.01 c | 0.42 ± 0.02 b | 0.49 ± 0.01 a | - | nutty aroma |
| Sulfur compounds | |||||||||
| 19 | 4-Methylthiazole | 832 | - | - | - | 0.84 ± 0.02 b | 0.94 ± 0.03 a | - | nutty, green |
| 20 | 2,4-Dimethylthiazole | 922 | - | 0.49 ± 0.02 d | 0.48 ± 0.02 d | 0.60 ± 0.03 c | 0.72 ± 0.01 b | 0.82 ± 0.06 a | like garlic |
| 21 | Dimethyl trisulfide | 972 | 0.67 ± 0.02 d | 0.87 ± 0.02 c | 0.96 ± 0.02 b | 1.10 ± 0.06 a | 1.14 ± 0.05 a | 0.78 ± 0.05 c | fresh onion |
| 22 | 2-Methyl-2-thiazoline | - | - | - | - | - | 1.16 ± 0.08 a | sulfurous | |
| 23 | 1-(2-Thienyl)-ethanone | 1030 | 0.57 ± 0.02 a | 0.37 ± 0.02 e | 0.40 ± 0.01 d | 0.48 ± 0.02 c | 0.53 ± 0.01 b | - | Sulfurous, nutty |
| Pyrroles | |||||||||
| 24 | 1-Methyl-1H-pyrrole-2-carboxaldehyde | 1054 | 1.73 ± 0.15 d | 1.74 ± 0.13 d | 1.67 ± 0.12 e | 1.89 ± 0.10 c | 2.25 ± 0.14 a | 2.12 ± 0.16 b | - |
| 25 | 1-Ethyl-1H-pyrrole-2-carboxaldehyde | 955 | 0.73 ± 0.07 b | 0.61 ± 0.06 c | 0.59 ± 0.04 c | 0.73 ± 0.04 ab | 0.86 ± 0.06 a | 0.79 ± 0.05 a | - |
| 26 | 1-(1H-Pyrrol-2-yl)-ethanone | 1035 | 2.81 ± 0.17 a | 1.88 ± 0.13 d | 1.66 ± 0.13 e | 2.17 ± 0.19 c | 2.52 ± 0.21 b | 2.26 ± 0.14 c | walnut |
| 27 | 1H-Pyrrole-2-carboxaldehyde | 988 | 5.08 ± 0.08 c | 5.00 ± 0.04 c | 4.95 ± 0.15 c | 6.05 ± 0.19 b | 6.62 ± 0.21 a | 5.25 ± 0.15 c | - |
| 28 | Methyl pyrrole-2-carboxylate | 1066 | 0.33 ± 0.04 b | 0.14 ± 0.01 b | 0.12 ± 0.01 b | 0.15 ± 0.02 b | 0.16 ± 0.02 a | - | - |
| Pyridines | |||||||||
| 29 | 2-Methyl-pyridine | 787 | - | 0.35 ± 0.03 c | 0.54 ± 0.02 b | 0.27 ± 0.01 c | 0.71 ± 0.08 a | 0.57 ± 0.01 b | unpleasant |
| 30 | 1-(2-Pyridinyl)-ethanone | 1023 | 0.50 ± 0.05 a | 0.38 ± 0.03 c | 0.36 ± 0.02 c | 0.49 ± 0.04 ab | 0.46 ± 0.03 b | 0.59 ± 0.04 a | tobacco-like |
| 31 | Methyl nicotinate | 1054 | 0.82 ± 0.06 a | 0.47 ± 0.03 d | 0.46 ± 0.04 d | 0.58 ± 0.05 c | 0.69 ± 0.06 b | 0.27 ± 0.05 e | caramellic nutty |
| Aldehydes | |||||||||
| 32 | Hexanal | 806 | - | - | - | - | 0.88 ± 0.05 a | - | fruity, woody |
| 33 | Furfural | 831 | 6.81 ± 0.25 a | 5.22 ± 0.21 c | 5.44 ± 0.24 c | 6.10 ± 0.12 b | 6.79 ± 0.13 a | 5.14 ± 0.31 c | almond-like |
| 34 | Benzaldehyde | 982 | 1.71 ± 0.11 d | 1.79 ± 0.10 d | 1.81 ± 0.08 d | 2.18 ± 0.16 b | 2.40 ± 0.27 a | 1.92 ± 0.12 c | almond-like |
| 35 | (E)-2-Octenal | 1013 | 1.14 ± 0.04 d | 1.24 ± 0.02 bc | 1.19 ± 0.05 cd | 1.33 ± 0.07 ab | 1.37 ± 0.05 a | 1.09 ± 0.08 d | cooked rice |
| 36 | Heptanal | 917 | - | - | - | - | - | 0.78 ± 0.06 a | fatty, rancid |
| Ketones | |||||||||
| 37 | 3-Octen-2-one | 960 | - | 0.03 ± 0.01 b | - | 0.03 ± 0.01 b | 0.12 ± 0.02 a | - | fruity, lemon |
| 38 | Isophorone | 1097 | - | 0.12 ± 0.01 b | 0.12 ± 0.02 b | 0.14 ± 0.01 a | 0.16 ± 0.01 a | 0.15 ± 0.01 a | like camphor |
| 39 | 1,4-Cyclohex-2-enedione | 1044 | 0.26 ± 0.02 a | 0.20 ± 0.01 b | 0.19 ± 0.02 b | 0.24 ± 0.02 b | 0.29 ± 0.02 a | - | - |
| 40 | Acetophenone | 1029 | 1.13 ± 0.03 d | 1.60 ± 0.08 c | 1.57 ± 0.05 c | 1.84 ± 0.06 b | 2.12 ± 0.11 a | 1.75 ± 0.11 b | oranges |
| 41 | 2-Octanone | 1007 | - | - | - | - | - | 0.56 ± 0.04 a | soapy, buttery |
| Phenols | |||||||||
| 42 | 2- Methoxy-phenol | 1090 | 8.79 ± 0.14 d | 9.62 ± 0.19 c | 8.93 ± 0.11 d | 11.18 ± 0.15 b | 12.81 ± 0.28 a | 7.56 ± 0.25 e | smoky |
| 43 | Phenol | 901 | 0.61 ± 0.03 a | 0.45 ± 0.03 c | 0.42 ± 0.02 c | 0.54 ± 0.04 b | 0.63 ± 0.05 a | 0.53 ± 0.04 b | fried meat |
| 44 | 4-Ethyl-2-methoxyphenol | 1303 | 0.51 ± 0.04 a | 0.30 ± 0.02 c | 0.27 ± 0.03 c | 0.36 ± 0.02 b | 0.29 ± 0.03 c | - | slightly sweet |
| 45 | 2-Methoxy-4-vinylphenol | 1293 | 0.96 ± 0.07 b | 0.81 ± 0.04 c | 0.68 ± 0.05 d | 0.91 ± 0.06 b | 1.17 ± 0.08 a | 0.88 ± 0.06 c | roasted peanut |
| 46 | 2,3-Methylenedioxyphenol | 1245 | 0.98 ± 0.09 c | 1.42 ± 0.08 b | 1.04 ± 0.06 c | 1.44 ± 0.07 b | 1.89 ± 0.06 a | 1.53 ± 0.05 b | - |
| Alcohols | |||||||||
| 47 | 1-Octen-3-ol | 969 | 1.12 ± 0.06 c | 1.00 ± 0.08 c | 1.06 ± 0.07 c | 1.22 ± 0.05 b | 1.37 ± 0.05 a | 1.23 ± 0.05 b | strong earthy |
| 48 | 1-Octanol | 1059 | - | 0.28 ± 0.02 b | 0.33 ± 0.07 ab | 0.34 ± 0.03 ab | 0.38 ± 0.03 a | 0.24 ± 0.03 b | orange–rose |
| 49 | Benzyl alcohol | 1036 | 0.18 ± 0.02 b | 0.17 ± 0.02 b | 0.15 ± 0.01 b | 0.18 ± 0.02 b | 0.23 ± 0.01 a | 0.14 ± 0.02 b | slightly sweet |
Note: Data are presented as mean ± SD and represent mean of three independent replicates. Values with different letters (a–e) within the same row of oils were significantly different (p < 0.05). “-” means not detected. 1 Kovats indices (KI) were determined by searching the mass spectrum in the database and manual interpretation. 2 Odors indicate the odor bias of some specific flavor compounds.