Comprehensive comparison of aroma profiles and chiral free and glycosidically bound volatiles in Fujian and Yunnan white teas.

[Display omitted] • Differences on aroma profiles between Fujian and Yunnan white teas were revealed. • 28 Chiral free and glycosidically bound volatiles were identified and compared. • Linalool and α-terpineol showed the opposite major configurations in two white teas. • Glycosidically bound linalool oxides were directly quantified for the first time. • Fujian and Yunnan white teas could be distinguished based on nine key compounds. The Fujian and Yunnan provinces in China are the most representative origins of white tea. However, the key differences in the chemical constituents of the two white teas have rarely been revealed. In this study, a comprehensive comparison of the aroma profiles, chiral volatiles, and glycosidically bound volatiles (GBVs) in Fujian and Yunnan white teas was performed, and 174 volatiles and 28 enantiomers, including 22 volatiles and six GBVs, were identified. Linalool, linalyl-β-primeveroside (LinPrim), and α-terpineol presented the opposite dominant configurations in Fujian and Yunnan white teas, and the chiral GBVs were firstly quantified with significant differences in the contents of R -LinPrim and β- d -glucopyranosides of (2 R , 5 R)-linalool oxide A and (2 R , 5 S)-linalool oxide B. Moreover, discrimination functions for Fujian and Yunnan white teas were created using nine key variables with excellent reliability and efficiency. These results provide a new method for objectively distinguishing authentic white teas according to geographical origin. [ABSTRACT FROM AUTHOR]