## 2 Results and Discussion
### Key Aroma Compounds Identified of Three Black Teas
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**No**} & \multirow{2}{*}{**Aroma**} & \multirow{2}{*}{**LRI a**} & \multirow{2}{*}{**Odor**} & \multirow{2}{*}{**Quality d**} & \multicolumn{2}{c}{**JJM**} & \multicolumn{2}{c}{**KM**} & \multicolumn{2}{c}{**DH**} & \multirow{2}{*}{**ID e**} \\  & & **Compounds** & **DB-5 b** & **Innova c** & **Quality d** & **AI** & **FD** & **AI** & **FD** & **AI** & **FD** & **AI** & **FD** \\ \hline
39 & Hotrienol & 1119 & 1614 & Lavender & 2.4 & 8 & 1.1 & 4 & 1.9 & 8 & RI, MS, A \\
40 & pyrrole-2- & 1029 & 1618 & Burnt, roasted, smoky & 5.2 & 128 & 6.9 & 256 & 4.9 & 64 & RI, MS, A \\
41 & Spaclostral & 1241 & 1625 & Tropical saffron, herbal & 4.1 & - & 5.8 & - & - & - & RI, MS, A \\
42 & (1R)-(-)- & - & 1634 & Sweet, minty & 3.6 & - & - & - & - & - & RI, MS, A \\
43 & Benzeneca & 1048 & 1654 & Floral, honey & 3.9 & 256 & 8.1 & 128 & 4.9 & 128 & RI, MS, A \\
44 & Fairfuryl alcohol & 1075 & 1665 & Sweet, caramel & 4.7 & 64 & - & - & 3.5 & 32 & RI, MS, A \\
45 & methylmonane- & 2/4-dione & 1445 & 1680 & Hay like & - & - & 5.5 & 64 & 3.6 & 16 & RI, MS, A \\
46 & Neral & 1247 & 1684 & Lemon peel, citrus & 4.6 & 64 & 5.3 & 64 & - & - & RI, MS, A \\
47 & Alpha- & 1199 & 1693 & Lilac, woody, & 2.2 & 16 & 1.8 & 8 & 1.8 & 8 & RI, MS, A \\
48 & Bernzyl acetate & 1164 & 1732 & Fruity, floral & 3.9 & 16 & 4.2 & 32 & - & - & RI, MS, A \\
49 & Naphthalene & 1209 & 1751 & Balmy & 0.8 & 8 & 1.1 & 16 & 0.9 & 8 & RI, MS, A \\
50 & Methyl & 1204 & 1785 & Wintergreen & 5.7 & 512 & 6.2 & 256 & 8.7 & 512 & RI, MS, A \\
51 & Nerol & 1230 & 1793 & Neroli, citrus & 3.9 & 64 & 4.4 & 128 & - & - & RI, MS, A \\
52 & Hexanoic acid & 986 & 1802 & Fatty, cheesy & 2.2 & 32 & 1.9 & 32 & 1.7 & 32 & RI, MS, A \\
53 & \(\beta\)- & 1386 & 1822 & Floral, fatty & - & - & 4.5 & 16 & - & - & RI, MS, A \\  & \(\alpha\)- & & & & & & & & & & \\
54 & Methylbenzyl & 1051 & 1827 & Fresh sweet & 4.6 & 64 & 2.1 & 32 & - & - & RI, MS, A \\  & alcohol & & & & & & & & & & \\
55 & Geraniol & 1235 & 1841 & Sweet, floral & 5.1 & 256 & 6.1 & 512 & 3.8 & 128 & RI, MS, A \\
56 & \(\alpha\)-Ionone & 1439 & 1858 & Woody & - & - & 2.1 & - & - & - & RI, MS, A \\
57 & Benzyl alcohol & 1030 & 1876 & Floral & 2.9 & 64 & 4.5 & 64 & 3.1 & 32 & RI, MS, A \\
58 & Phenylethyl & 1110 & 1912 & Rose, floral & 5.2 & 128 & 5.5 & 256 & 6.5 & 512 & RI, MS, A \\  & alcohol & 1019 & 1914 & Green, fruity & 3.6 & 64 & 4.3 & 128 & 3.8 & 128 & RI, MS, A \\
59 & (E)-2-hexenoic acid & - & 1917 & Fruity, sweet & 3.3 & 64 & 4.1 & 128 & 3.6 & 128 & RI, MS, A \\
60 & 2-Acetyl & 1065 & 1928 & Musty, sweet & 1.5 & 16 & 3.2 & 64 & 2.8 & 64 & RI, MS, A \\  & pyrrole & & & & & & & & & & \\
62 & 2-Denyi-2- & & 1281 & 1941 & Floral, black & 3.2 & - & 2.9 & - & 4.7 & - & RI, MS, A \\
63 & \(\beta\)-Ionone & 1494 & 1947 & Woody, floral & 3.6 & - & 3.4 & - & 3.7 & - & RI, MS, A \\
64 & cis-Jasmone & 1391 & 1955 & Woody, herbal & 3.9 & - & 4.5 & - & - & - & RI, MS, A \\
65 & 2-Formyl-1H- & 1015 & 1983 & Musty, beefy & 3.1 & 32 & 3.5 & 64 & 2.2 & 16 & RI, MS, A \\  & pyrrole & & & & & & & & & & \\
66 & 4-Methoxyben & 1251 & 2004 & Sweet, warm & - & - & - & 1.9 & 16 & RI, MS, A \\
67 & Geranic acid & 1349 & 2332 & Green, woody & 1.1 & 32 & 0.6 & 8 & 0.7 & 8 & RI, MS, A \\  & Dihydroac & 1495 & 2349 & Musk & - & 64 & - & 32 & - & - & RI, MS, A \\  & tinididide & & & & & & & & & & \\
69 & Benzoic acid & 1191 & 2442 & Faint, balsam & 0.5 & 4 & 0.7 & 8 & 3.5 & 16 & RI, MS, A \\
70 & Coumarin & 1435 & 2468 & Sweet & - & 32 & - & 16 & - & - & RI, MS, A \\ \hline \hline \end{tabular}  
* LRI, linear retention index; b DB-5, non-polar GC Column; c HP-Innowax, polar GC Column; d Odor quality perceived by GC-O analysis; e identification method, aroma(A), retention indices (RI) and mass spectra (MS) agree with the authentic compounds.  
\end{table} 
Table 1: _Cont._