## 2 Results
### Identification of Arona-Active Compounds in Citrus Blend Black Teas  
Active aromatic compounds were assessed in equal amounts of mixed samples from each group using GC-O/MS. Table 3 shows that at least three panelists recognized 61 active aromatic compounds (Supporting Information Tables S3-S5). By comprehensively combining the findings of panelists, we assigned 17 components to class A (fresh and green scents), 29 to class B (floral, fruity, or sweet scents), 9 to class C (herbal or woody scents), 2 to class D (bakery scents), and 4 to class E (unpleasant odor). The compounds in classes A and B might have directly contributed to the overall aroma quality of the citrus black teas owing to their similar scent types to sensory evaluation findings that all these samples have the obvious smell of fresh, fruity, sweet, and floral scents. Among them, heptanal (fresh, green; AI, 2.33-2.6), limonene (lemon-like, fruity, fresh; AI, 2.0-2.33), linalool (floral; AI, 2.57-3.29) and trans-\(\beta\)-ionone (floral; AI, 2.67-2.75) were detected in all groups. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Class [1]**} & \multirow{2}{*}{**No.**} & \multirow{2}{*}{**Compounds**} & \multicolumn{3}{c}{**Aroma Intensity**} & \multirow{2}{*}{**Order Characteristic**} \\ \cline{5-6}  & & & **CG** & & **BG** & **LG** \\ \hline \multirow{8}{*}{A} & 1 & Hexanal * & & 2.00 & 2.00 & Fresh \\  & 2 & Heptanal * & 2.60 & 2.57 & 2.33 & Fresh, Green \\  & 3 & \(\beta\)-Myrecne * & 3.17 & 2.00 & & Green, Metallic \\  & 4 & \(\beta\)-Pineinee * & & 2.71 & 3.17 & Green, wood \\  & 5 & Carveol * & & 2.00 & Fresh \\  & 6 & (\(E\),\(E\))-2,6-Dimethyl-2,4,6-octatriene & & 2.25 & & Fresh, Floral \\  & 7 & Citronellal & 2.50 & & Green, Wood \\  & 8 & 3,6-Dihydro-4-methyl-2- & & & & Green \\  & 8 & (2-methyl-1-propenyl)-2\(H\)-pyran & & & & Green \\  & 9 & 3-(Methylthio)-nonanal & & & 3.00 & Green, Wood \\  & 10 & Terpinen-4-ol * & & 2.83 & & Fresh, Wood \\  & 11 & Verbenol & & & 2.00 & Fresh, Herbal \\  & 12 & Ethyl octanoate & 3.00 & & & Green, Waxy \\  & 13 & 2-(\(n\)-Propyl)-pyrazine & 1.50 & & & Green, Limon-like \\  & 14 & 4-(1-Methylethyl)-benzaldehyde & 2.71 & & & Fresh, Herbal \\  & 15 & Bornyl acetate & 2.33 & & & Fresh, Wood \\  & 16 & Decanoic acid ethyl ester & & 2.33 & & Green, Fatty \\  & 17 & Dodecanal & 2.60 & & & Green, Waxy \\ \hline \multirow{8}{*}{22} & 18 & Ethyl butyrate & 2.67 & & & Fruity \\  & 19 & (\(E\))-2-Hexenal * & 2.43 & 1.33 & & Fruity \\  & 20 & Octanal * & 2.67 & & & Lemon-like, Fresh \\  & 21 & Nerol * & & 2.00 & & Floral, Sweet \\  & 4,6,6-Trimethylbicyclo[3.1.1] & & & & & Fruity \\  & 22 & hept-3-en-2-one & & & & \\  & 23 & Limonene * & 2.33 & 2.00 & 2.20 & Lemon-like, Fruity, \\  & 24 & Benzeneacetaldehyde * & 2.60 & & 2.25 & Floral \\  & 25 & \(\alpha\)-Pinee * & & & 3.17 & Floral \\  & 26 & Linalool * & 3.29 & 2.57 & 3.14 & Floral \\  & 27 & \(p\)-Mentha-1,8-dien-7-ol & 2.17 & & 2.20 & Floral, Green \\  & 28 & \(\alpha\)-Terpineol * & & 2.00 & 2.33 & Floral \\  & 29 & Decanal & 2.83 & & & Sweet \\ B & 30 & (\(Z\))-3,7-Dimethyl-2,6-octaI & & & 2.29 & Lemon-like, Fresh \\  & 31 & Geranoid * & & & 2.86 & Lemon-like, Fresh \\  & 32 & Linaly acetate * & & 2.57 & & Citrus-like, Herbal \\  & 33 & (\(E\))-3,7-Dimethyl-2,6-Octadienal & & & 2.40 & Lemon-like \\  & 34 & 3-Phenyl-2-propenal & 3.33 & & & Sweet, Wood, \\  & 35 & Citral & & & 2.67 & Lemon-like \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Active aromatic compounds identified in citrus blend black tea. The AI was notably highest for geranyl acetate (class B; AI, 3.29), \(\beta\)-pinene (class A; AI, 3.17), \(\alpha\)-pinene (class B; AI, 3.17), linalool (class B; AI, 3.14), 3-(methylthio)-nonanal (class A; AI, 3.0), most of which were in class B. In addition to the concentrated distribution of odorants in class B, more compounds in LG belonged to classes D and E, which differed with the other groups. GC-O/MS analysis identified 27, 23, and 29 active aromatic compounds in CG, BG, and LG, respectively.