## 3 Results and Discussion
### Analysis of Aroma-Active Compounds Based on AEDA and MF
#### 3.4.1 AEDA Results
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & & & & & **HY EO** & \multicolumn{2}{c}{**GF EO**} \\ \cline{3-8}
**No. \({}^{*}\)** & **Compounds** & **Identification** & **Odor Characteristic** & **MF\%** & **FD** & **MF\%** & **FD** \\ \hline
20 & Geraniol & MS, RI, O & citrus, floral & 63.74 & 32 & 71.44 & 512 \\
21 & Geraniol & MS, RI, O & citrus, lemon, floral & - & - & 60.38 & 4 \\
22 & 1-Decanol & MS, RI, O & fatty & 43.30 & 1 & 50.00 & 2 \\
23 & Thymol & MS, RI, O & woody, grass & 45.07 & 1 & - & - \\
24 & Carvacrol & MS, RI, O & chicken shift & 41.46 & 1 & 60.92 & 2 \\
25 & Unknown 5 & O & fatty & 68.47 & 64 & 76.03 & 1 \\
26 & Undecanal & MS, RI, O & aldehyde & 39.53 & 1 & 33.07 & 1 \\
27 & (_E,E_)-2,4-Decadial & MS, RI, O & tallowy, peanut & 46.77 & 8 & 58.63 & 32 \\
28 & Carvyl acetate & MS, RI, O & woody, fruity & 82.92 & 128 & 53.03 & 2 \\
29 & Unknown 6 & O & stinky & 61.24 & 1 & - & - \\
30 & Citronelliy acetate & MS, RI, O & fruity & 50.00 & 8 & - & - \\
31 & Unknown 7 & O & grass & 46.77 & 8 & - & - \\
32 & Yangene & MS, RI, O & fatty & - & - & 58.09 & 4 \\
33 & Copane & MS, RI, O & raw soybean & 81.97 & 32 & 81.28 & 32 \\
34 & \(\beta\)-Elemene & MS, RI, O & herbaceous & 55.90 & 16 & - & - \\
35 & Unknown 8 & O & metallic & 39.53 & 1 & - & - \\
36 & Dodecaal & MS, RI, O & aldehyde, tailowy & 79.06 & 16 & 76.03 & 4 \\
37 & _a_-Guaine & MS, RI, O & floral, woody & 50.00 & 4 & 43.30 & 1 \\
38 & _cis_-\(\beta\)-Farmesene & MS, RI, O & poker & 81.97 & 16 & 70.99 & 2 \\
39 & _trans_-2-Dodeceal & MS, RI, O & soapy, aldehyde & 76.03 & 32 & - & - \\
40 & \(\gamma\)-Muurolene & MS, RI, O & herbaceous & - & - & 25.00 & 1 \\
41 & Germacrene D & MS, RI, O & paper, ink & 70.71 & 128 & - & - \\
42 & Valencene & MS, RI, O & sweet, herbaceous & 37.50 & 8 & - & - \\
43 & Bicyclogermacene & MS, RI, O & green & 33.07 & 1 & - & - \\
44 & Unknown 9 & O & fruity, floral & 30.62 & 1 & 63.74 & 1 \\
45 & Elemol & MS, RI, O & scipy, stinky & 41.46 & 8 & 75.00 & 16 \\
46 & Germacrene B & MS, RI, O & woody & 76.03 & 128 & - & - \\
47 & Unknown 10 & O & stinky & 55.90 & 4 & - & - \\
48 & Unknown 11 & O & stinky & 73.95 & 8 & - & - \\
49 & Unknown 12 & O & grass, fruity & 86.60 & 128 & 35.36 & 2 \\
50 & _T_-Muurolol & MS, RI, O & stinky, fishy & 89.64 & 64 & 43.30 & 2 \\
51 & _a_-Cadinol & MS, RI, O & pungent & 87.50 & 256 & 59.95 & 16 \\
52 & _\(\beta\)-Fudecsmol & MS, RI, O & sweet & 43.30 & 64 & - & - \\
53 & \(\beta\)-Shensal & MS, RI, O & fishy & 100.00 & 32 & - & - \\
54 & Unknown 13 & O & woody & 59.95 & 2 & 48.41 & 8 \\
55 & 7-Methoxycomarin & MS, RI, O & sweet, cream & 81.01 & 16 & 81.97 & 32 \\
56 & Nootkatone & MS, RI, O & woody, grapruit & 99.22 & 256 & 45.07 & 2 \\
57 & 7-Hydroxycomarin & MS, RI, O & scorched & 57.28 & 1 & 54.01 & 8 \\
58 & Unknown 14 & O & sweet & - & - & 35.36 & 16 \\
59 & Unknown 15 & O & sweet & 54.49 & 16 & 50.00 & 2 \\ \hline \hline \end{tabular} \({}^{*}\)Odorants are numbered consecutively according to their elution order from the DB-5 ms column; \({}^{*}\)-\({}^{*}\) means not smelled; Unknown compounds are not identified by MS but smelled by sniffers. EOs, essential oils; HY, Huyou; GE, grapruit; AEDA, aroma extract dilution analysis; MF, modified frequency.  
\end{table} 
Table 2: _Cont._addition, other key aroma-active compounds with FD \(>\) 16 specific to HY EO included \(T\)-muurololol (FD = 64, stinky/fishy), \(\beta\)-eudesmol (FD = 64, sweet), unknown 5 (FD = 64, fatty), \(\beta\)-sinensal (FD = 32, fishy), _trans_-2-dodecenal (FD = 32, soapy/aldehyde), dodecanal (FD = 16, aldehyde/tallowy), _cis_-\(\beta\)-farnesene (FD = 16, poker) and unknown 15 (FD = 16, sweet), while decanal (FD = 64, aldehyde/tallowy/citrus), (_E_,_E_)-2,4-decadienal (FD = 32, tallowy/peanut), citronello1 (FD = 16, floral/fresh) and elemol (FD = 16, spicy/stinky) were specific to GFEO. Interestingly, 7-methoxycoumarin (FD = 16 and 32) was detected in the GC-O experiment and showed a pleasant sweet and cream aroma, although it is a nonvolatile compound usually identified by HPLC.