## 3 Results and Discussion
### Volatile Compounds Identified by GC-MS
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**No.**} & \multirow{2}{*}{**Volatile Compounds**} & \multicolumn{3}{c}{**Relative Content (\%)**} & \multirow{2}{*}{**Odor Description \#**} \\  & & **FTL** & **BT** & **GT** & \\ \hline  & [IS-(1.alpha\_3,beta\_3,beta\_4,4.alpha\_8,8a\_eta)]-1,4- & & & & \\
23 & decakhydro-1,5,58,4 tetramethyl & 0.03 & ND & ND & — \\  & -Methanoazena-3-0 & & & & \\
24 & 2,2-Dimethyl-6-methylene-1-3,5-dihydroxy-1- & & & & \\
24 & pentenyllycyclohexan-1-perhydrol & 0.08 & 0.17 & 0.05 & — \\
25 & tert-Hexadecanethiol & 0.04 & 0.4 & 0.14 & — \\
26 & Isocalamenediol & 0.44 & ND & ND & — \\
27 & shyobunol & ND & 2.83 & 1.22 & — \\
28 & Olivetol & 3.2 & ND & ND & — \\
**sum** & & **11.86** & **24.94** & **11.58** & \\
**Ketones** & & & & & \\
1 & 2-Nonadecanone & ND & ND & 0.03 & — \\
2 & sulcatone & ND & 0.81 & 1.75 & Green, fruity \\
3 & 2,2,6-trimethyl-Cyclohexanone & 0.11 & ND & ND & — \\
4 & Isophorone & 0.1 & ND & 0.08 & Cooling, woody, sweet, green, \\  & 5 & 3,5-Octadien-2-one & ND & ND & 2.91 & Rose-like, layered-like \\
6 & 3-Nonen-2-one & ND & 0.04 & ND & — \\
7 & 4-(2,2,6-Trimethyl-bicyclo [4.1.0]hept-1-yl)-2-butanol & 0.12 & ND & ND & — \\
8 & 5,9,9-trimethyl-Spiro [3.6] deca-5,7-dien-1-one & ND & ND & 0.06 & — \\
9 & 2-Hydroxycyclopentadecanone & ND & ND & 0.06 & — \\
10 & 4-(2,6,6-trimethyl-2-cyclohex-1-yl)3-Buten-2-one & 0.49 & 0.69 & 4.8 & — \\
11 & Geranyl acetone & 1.44 & 1.2 & 1.68 & Fresh, rose-like, floral, green, \\  & 12 & \(\beta\)-Ionone & 2.79 & 4.44 & 5.76 & Floraf, woody, sweet, fruity, berry \\
13 & 4-(4-hydroxy-2,2,6-trimethyl-7-oxabicyclo [4.1.0]hept-1-yl)-3-Buten-2-one & 2.45 & 0.9 & 1.24 & — \\
14 & 1\({}^{\prime}\)-carbethoxy-1-’cyano-1,2-dihydro-3’H- & 1.4 & 0.04 & 0.89 & — \\  & Cycloprop(1,2)-5-cholesterol-1-en-3-one & **8.9** & **8.12** & **19.26** & \\
**sum** & & & & & \\
**Esters** & & & & & \\
1 & Linaly acetate & ND & 0.25 & 0.07 & Fruity, floral \\
2 & (Z)-verbenyl acetate & ND & 0.33 & ND & — \\
2-Methyl-3-methylene-1-cyclopentancarboxylic acid & 0.66 & ND & ND & — \\
3 & methyl ester & & & & \\
4 & E-2-Hexenyl benzoate & ND & ND & 0.04 & — \\
5 & Acetic acid,3-(2,2- dimethyl-6-methylene- & & & \\ cyclohexylidene)-1-methyl-butyl ester & ND & ND & 0.12 & — \\
6 & Terpinyl formate & 0.27 & ND & ND & — \\
7 & Methyl salicylate & ND & 9.75 & 6.45 & Minty, wintergreen, grass odor \\  & Formic acid, & & ND & 0.27 & ND & — \\
8 & 3,7,11-trimethyl-1,6,10-dodecetrian-3-ylester & 0.26 & ND & ND & — \\
9 & Terpinyl Acetate & ND & 0.58 & ND & — \\
10 & Undec-10-ynoic acid, tridec-2-yn-1-ylester & 0.26 & ND & ND & — \\
11 & 2,5-Octadecadiynoicacid, methyl ester & ND & 0.21 & — \\
12 & Fumaric acid, 2-pentyl tridee-2-yn-1-yl ester & ND & 0.09 & ND & — \\
13 & Undec-10-ynoic acid, dodecyl ester & ND & ND & 0.02 & — \\
14 & Z-(13,14-Epoxy-tetrade-1-1-olacetate & 1.22 & ND & ND & — \\
15 & 10-Methyl-8-tetradecen-1-olacetate & 0.05 & 0.34 & ND & — \\
16 & Dascarpardian-1-methanol, acetate & 0.13 & 0.04 & 0.06 & — \\
17 & 7-Methyl-Z-tetradecen-1-olacetate & 0.38 & 0.58 & 0.28 & — \\
18 & Dihydroactinidiolide & 2.46 & 0.94 & 0.57 & Sweet, faint floral, herbal \\
19 & Ethyl iso-allocholate & 2.15 & 1.1 & 0.38 & — \\
**sum** & & **7.58** & **14.27** & **8.2** & \\
**Alkenes** & & & & & \\
1 & Styrene & 0.19 & ND & 0.45 & Floraf \\
2 & 3-Isopropyl-1-cyclohexene & ND & ND & 0.21 & — \\
3 & D-Limonene & 13.91 & 8.06 & 2.57 & Citrus, lemon, orange-like, green \\ \hline \hline \end{tabular}
\end{table} 
Table 2: \(Cont.\)Aldehydes, alcohols, and alkenes were the major volatiles in FTLs. The most abundant compounds were d-limonene, hexanal, linalool, and phenylethyl alcohol. D-limonene was responsible for the fruit odor, and the other three were the vital aroma compounds imparting floral odor in tea [1]. Heptanal has a grassy odor, and methyl salicate has a minty odor. They are the major contributors of green odor [31].