## 4 Conclusions  
In this work, the dynamic changes in the concentration of volatile compounds during the XYMJ green tea manufacturing were analyzed by HS-SPME combined with GC-MS, and the key odorants responsible for the aroma of XYMJ green tea were identified. A total of 73 volatile compounds in six different chemical classes were determined in the processed XYMJ green tea samples. The manufacturing processes resulted in the losses of total volatile compounds, which decreased by 73.3%. Among the identified volatile compounds, twenty-four aroma-active compounds, such as trans-nerolidol (10,199.4), geranylacetone (3436.5), nonanal (3190.1), (+)-\(\delta\)-cadinene (1881.0), linalool (838.0), (Z)-jasmone (465.6), cis-3-hexenyl butyrate (220.6), cis-3-hexenyl hexanoate (189.0), methyl jasmonate (125.1), and \(\beta\)-ocimene (92.4), were identified as the key odorants of XYMJ green tea based on OAV. The key odorants are mainly VTs and FADVs. Spreading significantly increased the concentrations of trans-nerolidol, trans-furan linalool oxide, methyl jasmonate, dihydroactinolide, (Z)-jasmone, geranial, phytol acetate, \(\beta\)-ocimene, \(\beta\)-myrcene and D-limonene, while significantly decreased the concentrations of nonanal, linalool, cis-3-hexenyl butyrate, cis-3-hexenyl hexane, cis-3-hexenyl valerate and cis-\(\beta\)-farnesene. Proper spreading is beneficial for the aroma formation of XYMJ green tea. Except for (+)-\(\delta\)-cadinene, copaene, cis-\(\beta\)-farnesene, (Z,E)-\(\alpha\)-farnesene and phytol acetate, the key odorants significantly decreased after fixing. The PCoA and HCA analyses suggested that fixing was the crucial process step for the aroma formation of XYMJ green tea. These findings of this study provide meaningful information for the manufacturing and quality control of XYMJ green tea.  
Conceptualization, P.Y., G.-M.W. and Z.-H.L.; methodology, J.-J.W. and Y.-S.K.; validation, P.Y., G.-Y.G. and G.-M.W.; formal analysis, P.Y.; investigation, P.Y.; resources, J.-W.Z., H.L. and X.W.; data curation, P.Y. and J.-J.W.; writing--original draft preparation, P.Y.; writing--review and editing, G.-M.W. and Z.-H.L.; visualization, Y.Z.; supervision, G.-Y.G.; project administration, Z.-H.L.; funding acquisition, P.Y. and Z.-H.L. All authors have read and agreed to the published version of the manuscript.  
Figure 8: Aroma shape of the processed XYMJ green tea samples based on the top twenty odorants with high OAVs, namely trans-nerolidol (1), geranylacetone (2), nonanal (3), (+)-\(\delta\)-cadinene (4), linalool (5), (Z)-jasmone (6), cis-3-hexenyl butyrate (7), cis-3-hexenyl hexanoate (8), methyl jasmonate (9), \(\beta\)-ocimene (10), \(\beta\)-myrcene (11), copaene (12), cis-\(\beta\)-farnesene (13), D-limonene (14), (E)-\(\beta\)-ocimene (15), dihydroactinolide (16), M-cymene (17), (Z,E)-\(\alpha\)-farnesene (18), methyl salicate (19), and geranial (20).  
**Funding:** This research was funded by the Science and Technology Project of Henan Province (212102110115, 212102110117, 222102210300), China Agriculture Research System of MOF and MARA (CARS-23), the National Key Research and Development Program of China (2019 YFD1001601), the Academic Rookie Program of Xinyang Agriculture and Forestry University (2021) and the Innovative Research Team of Xinyang Agriculture and Forestry University (20 XXJTD-003, KJCXTD-202003).  
**Institutional Review Board Statement:** Not applicate.  
**Informed Consent Statement:** Not applicate.  
**Data Availability Statement:** Not applicable.  
**Acknowledgments:** We appreciate [PERSON] from Fruit and Tea Research Institute, Hubei Academy of Agricultural Sciences and [PERSON] from College of Tea Science, Xinyang Agriculture and Forestry University for their helpful suggestions.  
**Conflicts of Interest:** The authors declare no conflict of interest.