## 3 Results and Discussion
### Aroma Recombination and Omission Test  
To confirm the contributions of these compounds with OAVs greater than or equal to one, the aroma recombination test was designed and performed. The deodorized SBT was used as a blank matrix. An SBT sample was randomly selected as a reference for aroma recombination. Then, 21 compounds with OAVs greater than 1 were added to the deodorized tea based on the quantitative results of the reference sun-dried black tea and mixed well. The recombination sample was sealed and kept for 24 h at 4 \({}^{\circ}\)C before sensory analysis. The recombination sample and selected reference sun-dried black tea were evaluated by 10 experienced assessors according to the \"Methodology for Sensory Evaluation of Tea (Chinese Standards, GB/T 23776-2018)\" described in Section 2.7. Six odor terms, including floral, fruity, green/grass, sweet, woody, and unpleasant flavor were identified as the main aroma characteristics based on the sensory results of SBT samples. The sensory results of the recombination sample and selected reference sample are shown in Figure 2. The results showed that the odor profile of the SBT could be successfully imitated to a certain extent by combining these 21 odor-active compounds at their detected concentrations in the selected reference sample, specifically in terms of its floral, fruity, green/grass, and sweet scents. The recombination sample was more inclined to a woody scent. This phenomenon may be due to the conversion of the non-volatile components while preparing the deodorized matrix or the difference in the extraction amounts of odor-active compounds while brewing (the odor-active compounds of the recombination sample were easier to give off). Overall, the results of odor recombination further verified the accuracy of the identified key odor-active compounds in SBT. In order to deeply verify the contributions of a single odor-active compound with OAVs greater than or equal to 1 to the aroma profile of SBT, the omission test was performed by designing 25 models, in which a single odor-active compound or a group of odor-active compounds was omitted. Taking the recombination sample as a reference, 25 omission models were evaluated by triangle test, and the results are supplied in Table 3.  
Model 1 showed that 10 assessors were able to perceive the entire omission of all alcohols (including linalool, geraniol, phenylethyl alcohol, (\(E\))-nerolidol, linalool oxide II, 1-octen-3-ol, linalool oxide I, and \(\alpha\)-terpineol) with a very high significance (\(p\leq 0.001\)), indicating that these alcohols played a major role in the aroma formation of SBT. Compared with the recombination sample, the single omission of linalool (model 1-1), geraniol (model 1-2), or phenylethyl alcohol (model 1-3) showed a very high significant difference (\(p\leq 0.001\)), a high significant difference (\(p\leq 0.01\)), and significant difference (\(p\leq 0.05\)), respectively. While the single omission of (\(E\))-nerolidol (model 1-4), linalool oxide II (model 1-5), 1-octen-3-ol (model 1-6), linalool oxide I (model 1-7), or \(\alpha\)-terpineol (model 1-8) showed no significant difference (\(p>0.05\)), indicating that the effect of these compounds on the aroma profile of SBT is relatively small. Model 2 showed that 10 assessors were able to perceive the entire omission of all ketones (including (\(E\))-\(\beta\)-damascenone, \(\beta\)-ionone, dihydro-\(\beta\)-ionone, \(\alpha\)-ionone, and geranyl acetone) also with a very high significance (\(p\leq 0.001\)). The single omission of (\(E\))-\(\beta\)-damascenone (model 2-1), \(\beta\)-ionone (model 2-2), or dihydro-\(\beta\)-ionone (model 2-3) also  
Figure 2: Aroma profile of the recombination sample and the sun-dried black tea. \begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Model**} & **Odor-Active Compounds Omitted** & **No. a ** \\  & **from the Recombination Sample** & **No.