# Characterization of the Key Aroma Compounds in Different Aroma Types of Chinese Yellow Tea
## 3 Results and Discussion
### Key Aroma Compounds in Different Aroma Types of Yellow Tea
\begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline \multicolumn{1}{c}{**Compounds**} & \multicolumn{1}{c}{**CAS**} & \multicolumn{1}{c}{**RI \({}^{\prime}\)/RI\({}^{\circ}\)**} & \multicolumn{1}{c}{**Identification\({}^{\circ}\)**} & \multicolumn{1}{c}{**Concentration \({}^{\circ}\)ergL\({  
\begin{table}
\begin{tabular}{l c c c c c c c} \hline \hline \multicolumn{1}{c}{**Compounds**} & \multicolumn{1}{c}{**CAS**} & \multicolumn{1}{c}{**RI\({}^{\prime}\)/RI\({}^{\prime}\)**} & \multicolumn{1}{c}{**Identification\({}^{\prime}\)**} & \multicolumn{1}{c}{**Facial Fragance Type**} & \multicolumn{1}{c}{**High-Fixed Fragance Type**} & \multicolumn{1}{c}{**Facial Fragance Type**} & \multicolumn{1}{c}{**Cen-Like Fragance Type**} \\ \hline \multicolumn{1}{c}{**Coustering**} & \multicolumn{1}{c}{**CAS**} & \multicolumn{1}{c}{**RI\({}^{\prime}\)/RI\({}^{\prime}\)**} & \multicolumn{1}{c}{**Identification\({}^{\prime}\)**} & \multicolumn{1}{c}{**Concentration split\({}^{\prime}\)**} & \multicolumn{1}{c}{**Concentration split\({}^{\prime}\)**} & \multicolumn{1}{c}{**Facial**} \\ \hline \multicolumn{1}{c}{**Acrosphemance**} & 96-86-2 & 1062/1063 & MS, BL, STD & 199.32 + 155.91a & 36.99 + 3.09b & 2.23 + 4.33b & 11.06 + 7.62b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 79-77-47 & 1485/1484 & MS, BL, STD & 20.77 + 18.52a & 6.56 + 10.27b & 154 + 2.07b & 2.15 + 6.59b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 78-20-2 & 1159/1141 & MS, BL, STD & 7.28 + 55.3a & 0.37 + 0.41b & 0.07 + 0.15b & 42.8 + 6.72b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 585-21 & 967/980 & MS, BL, STD & 20.67 + 15.03a & 5.29 + 3.82b & 31.35 + 3.32b & 3.81 + 2.59b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & \multicolumn{1}{c}{**Facial/Distances/1**} & \multicolumn{1}{c}{**58-20**} & \multicolumn{1}{c}{**156-786**} & MS, BL, STD & 0.77 + 18.9a & 0.0 + 0.0 & 0.0 & 0.0 \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 488-104 & 1062/1063 & MS, BL, STD & 172.74 + 29.4a & 0.25 + 0.37b & 19.99 + 1.99b & 0.58 + 0.98b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 739-70-1 & 1485/1485 & MS, BL, STD & 18.46 + 5.82a & 0.34 + 1.34b & 2.49 + 1.38b & 5.88 + 2.33b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 1728-91 & 1485/1485 & MS, BL, STD & 11.72 + 15.8a & 100.8 + 0.04b & 7.98 + 0.05b & 8.94 + 0.08b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 149-77-97 & 777/88 & MS, BL, STD & 70.77 + 8.7a & 5.1 + 3.56b & 7.92 + 3.32b & 13.82 + 1.62b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 144-97-93 & 1155/141 & MS, BL, STD & 14.24 + 6.77a & 6.53 + 1.09b & 15.2 + 3.18b & 15.24 + 2.46b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 127-41-3 & 1255/1425 & MS, BL, STD & 34.35 + 5.82a & 15.55 + 1.19b & 10.42 + 0.28b & 10.08 + 0.5b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 1238-93 & 1482/1483 & MS, BL, STD & 21.66 + 23.04a & 0.17 + 0.03b & 9.58 + 0.08b & 9.59 + 0.15b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 110-90 & 988/98 & MS, BL, STD & 19.19 + 11.38a & 2.29 + 0.33b & 3.25 + 2.28 & 13.53 + 5.82b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 99-99 & 1170/1168 & MS, BL, STD & 19.11 + 0.08 & 0.11 + 0.09b & 0.08 + 0.02b & 0.08 + 0.08b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 99-99 & 1170/1168 & MS, BL, STD & 42.18 + 4.09b & 2.27 + 0.36b & 0.11 + 0.07b & 0.41 + 0.45b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 84-99 & 1869/1870 & MS, BL, STD & 14.81 + 0.09b & 0.8 + 0.52b & 0.31 + 0.11b & 0.18 + 0.07b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 69-99 & 1970/1972 & MS, BL, STD & 0.0 + 0.0 & 0.0 + 0.0 & 0.04 + 0.44b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 355-86-1 & 1184/1235 & MS, BL, STD & 13.78 + 14.61a & 0.33 + 0.24b & 1.13 + 1.29b & 0.98 + 1.84b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 355-87 & 1301-11 & MS, BL, STD & 7.00 + 7.29a & 2.23 + 3.09b & 0.82 + 1.42b & 1.85 + 2.98b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 78-20-2 & 138 & MS, BL, STD & 3.66 + 23.2a & 0.29 + 0.32b & 0.12 + 0.45b & 0.14 + 0.08b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 525-86 & 1566/1568 & MS, BL, STD & 11.31 + 0.15a & 1.36 + 0.75b & 1.51 + 0.14b & 1.48 + 0.22b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 168-36 & 1186/1185 & MS, BL, STD & 7.35 + 18.21a & 0.21 + 1.23b & 1.26 + 3.23b & 0.35 + 0.45b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 140-11 & 1169/1126 & MS, BL, STD & 14.66 + 12.5a & 2.86 + 0.48b & 0.48 + 0.31b & 0.68 + 0.5b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 123-45 & 1969/997 & MS, BL, STD & 17.06 + 18.06a & 17.99 + 18.4b & 18.33 + 0.84b & 0.94 + 0.84b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 123-58 & 128/1728 & MS, BL, STD & 6.22 + 30.87a & 0.37 + 5.2b & 0.49 + 1.60b & 3.26 + 0.41b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 115-65 & 128/1728 & MS, BL, STD & 13.32 + 7.28a & 0.137 + 4.45b & 1.37 + 4.18b & 1.41 + 0.15b \\ \multicolumn{1}{c}{**\(p\)-fluence**} & 112-90 & 1290/1296 & MS, BL, STD & 19.0 + 0.6 + 0.5 & 80.6 + 0.57b & 3.98 + 1.19b & 3.06 +Combined with the results of OPLS-DA, a total of 47 discriminative aroma compounds were identified in the four aroma types of yellow tea based on the three conditions: the values of predictive component variable importance in the projection (VIP) \(\geq\) 1.0, \(p\)\(\leq\) 0.05 and OAV \(>\) 1 (Figure 3).