Abstract: The effect of different plucking season on aroma constituents in Lingtoudancong Oolong tea was investigated by gas chromatography and mass spectrometry analysis. Results showed that the tea which plucked in summer possessed more kinds of aroma constituents, higher total essential oil and lower concentration of flower aroma constituents. The tea plucked in spring and autumn possessed fewer kinds of aromatic constituents, lower amounts of essential oil, but with higher concentration of characteristic aroma constituents. The difference of characteristic aroma constituents expressed in the contents of linalool and linalool oxide in different plucking season. The tea plucked in autumn and spring seasons showed lower content of linalool and linalool oxide (50.98%~51.72%). However tea plucked in summer season showed a higher content of linalool oxide, cadinol and muurolene (more than 70.33%). The concentration of essential constituents such as α-citral, indole, jasmone and nerolidol are higher in autumn tea than those in other teas. The result of sensory evaluation showed that the sensory quality score of autumn tea is higher.

Key words: lingtoudancong, oolong tea, fermentation, plucking season, aroma constituents