## 4 Conclusions  
In this study, sensory evaluation and HS-SPME-GC-MS combined with rOAV were used to explore seasonal differences in the aroma quality and volatile components of Rucheng Baimao black tea. The results of sensory evaluation showed that black teas in spring, summer, and autumn all had floral aroma characteristics. The aroma quality of Rucheng Baimao spring black tea was the best, followed by autumn black tea, and summer black tea was the worst. The detection of volatile components revealed that a total of 140 volatile components were detected in black teas from different seasons. Among them, alcohols, esters, and alkanes were the main categories of volatile components. The overall trend of the relative content of volatile components was summer black tea > spring black tea > autumn black tea. The dominant volatile components in black teas of different seasons also varied. Geraniol had the highest relative content in spring black tea, linalool had the highest relative content in summer and autumn black teas, and methyl salicylate ranked second in black teas of all three seasons. The aroma index analysis indicated that the aroma quality of spring black tea was the best, followed by autumn black tea, and summer black tea was the worst, which confirmed the results of sensory evaluation. Using multivariate statistical analysis, 34 differential volatile components were screened out which could be used as potential substances to distinguish black teas of different seasons. By combining VIP \(>\) 1, \(p\) \(<\) 0.05, and rOAV \(>\) 1, 11 key differential volatile components were selected from black teas of different seasons. Geraniol, methyl salicylate, nonanal, and (\(E\))-citral accumulated the most in spring black tea, linalool, phenylacetaldehyde, benzaldehyde, phenethyl alcohol, benzyl alcohol, and \(\beta\)-ionone accumulated the most in summer black tea, and _trans_-nerolidol accumulated the most in autumn black tea. The differences in their distribution in black teas of different seasons were the material basis for the seasonal differences in the aroma quality of Rucheng Baimao black tea. The results of this study are helpful for deepening the understanding of the aroma components of Rucheng Baimao black tea and provide a certain reference for the regulation of its aroma quality. However, this study still has certain limitations. On the one hand, the influence of volatile components on the aroma quality of black tea is not merely singular. The interactions between volatile components can also have an impact on the aroma quality of black tea. On the other hand, the sensory evaluation of tea in this study mainly relies on human judgment. Although five individuals were selected in this study to reduce the subjective biases in sensory evaluation, there are still defects of being not completely objective. Based on this, in future research, it is imperative to utilize molecular sensory omics methods such as triangle tests, electronic noses, gas chromatography-olfactometry (GC-O), aroma recombination, and aroma omission to deeply explore the aroma quality of Rucheng Baimao black tea. **Supplementary Materials:** The following supporting information can be downloaded at [[https://www.mdpi.com/article/10.3390/foods14050763/s1](https://www.mdpi.com/article/10.3390/foods14050763/s1)]([https://www.mdpi.com/article/10.3390/foods14050763/s1](https://www.mdpi.com/article/10.3390/foods14050763/s1)), Table S1: Volatile components of Rucheng Baimao black tea in different seasons. **Author Contributions:** Conceptualization, H.W. and Y.Z. ; methodology, J.Z. ; software, J.Z. ; validation, J.Z. ; formal analysis, J.Z. ; investigation, J.Z. ; resources, H.W. ; data curation, J.Z. ; writing--original draft preparation, J.Z. ; writing--review and editing, H.W. and Y.Z. ; visualization, J.Z. ; supervision, H.W. and Y.Z. ; project administration, H.W. ; funding acquisition, H.W. All authors have read and agreed to the published version of the manuscript.