Table 1.
Relative percentage of volatile components in Egyptian dukkah and Syrian za’atar analyzed using headspace SPME-GCMS. Each presented value is a mean ± SD (n = 3).
| No. | RT (min) | Name | RI | EDT a | EDN b | SZT c | SZS d |
|---|---|---|---|---|---|---|---|
| 1 | 5.84 | 3-Hexen-1-ol | 807 | 0.01 ± 0.02 | 0.02 ± 0.01 | 0.02 ± 0.00 | 0.04 ± 0.01 |
| 2 | 8.01 | Linalool | 1083 | 0.32 ± 0.12 | 0.25 ± 0.12 | 0.17 ± 0.04 | 1.78 ± 0.32 |
| 3 | 8.78 | Borneol | 1162 | 0.00 ± 0.01 | 0.04 ± 0.02 | - | - |
| 4 | 8.96 | 4-Terpineol | 1170 | 0.73 ± 0.09 | 0.34 ± 0.08 | 0.17 ± 0.00 | 0.07 ± 0.01 |
| 5 | 9.03 | p-Cymene-8-ol | 1175 | 0.24 ± 0.05 | 0.24 ± 0.03 | 0.03 ± 0.01 | 0.07 ± 0.03 |
| Alcohols | Total | 1.30 | 0.89 | 0.40 | 1.97 | ||
| 6 | 4.17 | Hexanal | 734 | 0.04 ± 0.02 | 0.02 ± 0.01 | 0.01 ± 0.00 | 0.01 ± 0.00 |
| 7 | 6.70 | Benzaldehyde | 937 | 0.75 ± 0.04 | 1.43 ± 0.50 | 0.93 ± 0.03 | 0.49 ± 0.04 |
| 8 | 7.24 | n-Octanal | 984 | 0.42 ± 0.15 | 0.74 ± 0.16 | 1.98 ± 0.11 | 1.67 ± 0.29 |
| 9 | 8.09 | Nonanal | 1091 | 0.02 ± 0.00 | 0.05 ± 0.01 | - | 0.02 ± 0.00 |
| 10 | 9.59 | Cumin aldehyde | 1234 | 1.94 ± 0.36 | 1.04 ± 0.16 | 0.04 ± 0.03 | 0.54 ± 0.15 |
| 11 | 9.73 | p-Anisaldehyde | 1247 | 0.62 ± 0.15 | 0.23 ± 0.06 | 1.63 ± 0.11 | 7.51 ± 2.12 |
| Aldehydes | Total | 3.79 | 3.50 | 4.59 | 10.24 | ||
| 12 | 6.48 | Styrene | 853 | 0.18 ± 0.14 | 0.36 ± 0.11 | 0.20 ± 0.12 | 0.46 ± 0.10 |
| 13 | 7.27 | β-Cymene | 1003 | 0.02 ± 0.01 | 0.02 ± 0.02 | 0.05 ± 0.01 | 0.06 ± 0.03 |
| 14 | 7.99 | p-Dimethylstyrene | 1080 | 0.42 ± 0.16 | 0.22 ± 0.01 | 0.11 ± 0.00 | 0.22 ± 0.05 |
| 15 | 11.81 | α-Curcumene | 1461 | 0.85 ± 0.36 | 0.56 ± 0.10 | 0.20 ± 0.05 | 0.13 ± 0.04 |
| Aromatics | Total | 1.46 | 1.17 | 0.56 | 0.88 | ||
| 16 | 6.87 | n-Caproic acid | 955 | 0.72 ± 0.11 | 1.66 ± 0.09 | 0.43 ± 0.04 | 0.34 ± 0.03 |
| 17 | 8.74 | n-Caprylic acid | 1149 | 0.11 ± 0.04 | 0.21 ± 0.02 | 0.06 ± 0.01 | 0.04 ± 0.01 |
| Carboxylic acids | Total | 0.83 | 1.87 | 0.50 | 0.37 | ||
| 18 | 9.49 | Fenchyl acetate | 1226 | 0.02 ± 0.01 | 0.02 ± 0.01 | 0.02 ± 0.02 | 0.01 ± 0.00 |
| 19 | 10.60 | Terpinyl acetate | 1339 | 0.24 ± 0.08 | 1.96 ± 0.25 | 0.01 ± 0.01 | 0.13 ± 0.03 |
| 20 | 10.84 | Geranyl acetate | 1364 | 0.19 ± 0.07 | 1.09 ± 0.00 | 0.01 ± 0.01 | 0.11 ± 0.02 |
| 21 | 11.36 | Ethyl linoleate | 1453 | 0.32 ± 0.06 | 0.16 ± 0.03 | 0.11 ± 0.01 | 0.03 ± 0.01 |
| 22 | 11.79 | Methyl linolelaidate | 1459 | 0.20 ± 0.09 | 0.06 ± 0.09 | 0.06 ± 0.01 | 0.03 ± 0.00 |
| Esters | Total | 0.97 | 3.30 | 0.21 | 0.31 | ||
| 23 | 7.35 | Cineole | 1020 | 0.25 ± 0.09 | 0.60 ± 0.06 | 0.03 ± 0.02 | 0.21 ± 0.03 |
| 24 | 9.15 | Estragole | 1188 | 35.45 ± 1.17 c,d | 28.97 ± 4.26 c,d | 2.84 ± 0.97 a,b | 9.10 ± 2.45 a,b |
| 25 | 9.42 | O-Methylthymol | 1222 | 0.01 ± 0.00 | 0.51 ± 0.40 | - | - |
| 26 | 10.02 | Anethole | 1277 | 17.43 ± 1.99 | 7.51 ± 1.94 | 13.64 ± 0.10 | 25.40 ± 14.22 |
| Ethers | Total | 53.14 | 37.60 | 16.51 | 34.71 | ||
| 27 | 4.69 | Furfural | 777 | 0.01 ± 0.02 | 0.13 ± 0.10 | 0.54 ± 0.07 | 0.52 ± 0.03 |
| 28 | 6.71 | 5-Methyl-2-Furaldehyde | 942 | 1.62 ± 0.08 | 3.07 ± 0.42 | 1.67 ± 0.16 | 0.89 ± 0.04 |
| 29 | 7.64 | Furaneol | 1043 | 0.04 ± 0.01 | 0.07 ± 0.04 | 0.36 ± 0.08 | 0.12 ± 0.03 |
| 30 | 7.83 | 5-formylfurfural | 1065 | 0.37 ± 0.00 | 2.11 ± 1.13 | 0.12 ± 0.02 | 0.13 ± 0.03 |
| 31 | 9.38 | 5-Hydroxymethylfurfural | 1211 | 0.44 ± 0.18 | 4.59 ± 3.86 | 0.08 ± 0.04 | 0.12 ± 0.02 |
| Furans | Total | 2.48 | 9.96 | 2.76 | 1.78 | ||
| 32 | 8.00 | Fenchone | 1082 | 0.03 ± 0.02 | 0.01 ± 0.01 | 0.01 ± 0.00 | 0.17 ± 0.01 |
| 33 | 8.19 | Maltol | 1103 | 0.38 ± 0.06 | 0.83 ± 0.42 | 0.03 ± 0.01 | 0.20 ± 0.01 |
| 34 | 8.64 | Camphor | 1141 | 0.47 ± 0.00 | 1.24 ± 0.17 | 0.02 ± 0.00 | 0.26 ± 0.04 |
| 35 | 9.16 | Dihydrocarvone | 1197 | 0.62 ± 0.06 | 0.48 ± 0.16 | 0.03 ± 0.02 | 0.19 ± 0.08 |
| 36 | 9.63 | Carvone | 1237 | 12.09 ± 3.30 c,d | 14.83 ± 5.58 c,d | 1.06 ± 0.30 a,b,d | 4.77 ± 1.15 a,b,c |
| Ketones | Total | 13.58 | 17.38 | 1.16 | 5.58 | ||
| 37 | 6.52 | α-Thujene | 906 | 0.10 ± 0.00 | 0.43 ± 0.35 | 0.41 ± 0.37 | 0.99 ± 0.33 |
| 38 | 6.69 | Camphene | 925 | 0.04 ± 0.04 | 0.25 ± 0.35 | 0.07 ± 0.02 | 0.05 ± 0.04 |
| 39 | 6.93 | β-Myrcene | 961 | 6.95 ± 1.89 c,d | 7.62 ± 0.57 c,d | 19.49 ± 1.01 a,b | 16.15 ± 2.79 a,b |
| 40 | 7.23 | β-Pinene | 971 | 1.89 ± 0.47 | 2.08 ± 0.17 | 5.44 ± 0.27 | 4.54 ± 0.78 |
| 41 | 7.26 | α-Terpinene | 1002 | 0.21 ± 0.06 | 0.23 ± 0.02 | 0.60 ± 0.03 | 0.51 ± 0.08 |
| 42 | 7.31 | D-Limonene | 1016 | 6.44 ± 0.76 d | 6.06 ± 1.65 d | 5.55 ± 0.56 d | 9.06 ± 0.71 a,b,c |
| 43 | 7.35 | β-cis-Ocimene | 1027 | 0.18 ± 0.02 | 0.49 ± 0.00 | 0.04 ± 0.00 | 0.15 ± 0.02 |
| 44 | 7.45 | β-Ocimene | 1033 | 0.16 ± 0.04 | 0.37 ± 0.04 | 0.04 ± 0.00 | 0.17 ± 0.05 |
| 45 | 7.58 | γ-Terpinene | 1042 | 0.24 ± 0.11 | 0.27 ± 0.06 | 0.15 ± 0.02 | 0.06 ± 0.06 |
| 46 | 8.45 | Neo-allo-ocimene | 1117 | 0.03 ± 0.02 | 0.04 ± 0.02 | 0.01 ± 0.00 | 0.02 ± 0.00 |
| Monoterpene hydrocarbons | Total | 16.23 | 17.84 | 31.78 | 31.70 | ||
| 47 | 4.68 | 2-Methylpyrazine | 763 | 0.05 ± 0.08 | 0.09 ± 0.08 | 0.05 ± 0.03 | 0.03 ± 0.00 |
| 48 | 6.49 | 2,5-Dimethylpyrazine | 876 | 0.06 ± 0.02 | 0.48 ± 0.23 | 0.47 ± 0.18 | 0.71 ± 0.46 |
| 49 | 7.70 | α-Aminoxypropionic acid | 1056 | 0.04 ± 0.06 | 0.07 ± 0.08 | 0.08 ± 0.00 | 0.03 ± 0.03 |
| Nitrogen-containing compounds | Total | 0.16 | 0.64 | 0.60 | 0.77 | ||
| 50 | 7.82 | Linalool oxide | 1062 | 0.22 ± 0.01 | 1.26 ± 0.68 | 0.07 ± 0.01 | 0.10 ± 0.01 |
| Oxides | Total | 0.22 | 1.26 | 0.07 | 0.10 | ||
| 51 | 10.10 | Carvacrol | 1287 | 3.91 ± 1.18 c | 2.67 ± 0.53 c | 37.43 ± 4.33 a,b,d | 8.84 ± 1.76 c |
| Phenols | Total | 3.91 | 2.67 | 37.43 | 8.84 | ||
| 52 | 8.57 | Pyranone | 1133 | 0.02 ± 0.00 | 0.31 ± 0.25 | 0.01 ± 0.00 | 0.02 ± 0.01 |
| Pyrans | Total | 0.02 | 0.31 | 0.01 | 0.02 | ||
| 53 | 7.25 | Pyrrole-2-aldehyde | 991 | 0.61 ± 0.16 | 0.63 ± 0.30 | 2.94 ± 0.13 | 2.49 ± 0.44 |
| 54 | 8.24 | 2-Formyl-1-methylpyrrole | 1110 | 0.03 ± 0.02 | 0.18 ± 0.04 | 0.08 ± 0.01 | 0.10 ± 0.03 |
| Pyrroles | Total | 0.65 | 0.81 | 3.02 | 2.58 | ||
| 55 | 10.53 | δ-EIemene | 1332 | 0.03 ± 0.01 | 0.11 ± 0.02 | 0.02 ± 0.00 | 0.02 ± 0.00 |
| 56 | 10.98 | Bourbonene | 1383 | 0.13 ± 0.05 | 0.18 ± 0.03 | 0.02 ± 0.01 | 0.04 ± 0.00 |
| 57 | 11.33 | β-Caryophyllene | 1416 | 1.03 ± 0.21 | 0.49 ± 0.11 | 0.36 ± 0.03 | 0.11 ± 0.02 |
| 58 | 11.34 | Himachalene | 1443 | 0.06 ± 0.02 | 0.02 ± 0.01 | 0.02 ± 0.00 | - |
| Sesquiterpene hydrocarbons | Total | 1.25 | 0.80 | 0.42 | 0.17 | ||
Different letters (a, b, c, d) indicate significant differences of the major characteristic constituents between groups.