Effect of Different Plucking Season on Aroma Quatity of Lingtoudancong Oolong Tea by Deep Fermentation

The effect of different plucking season on aroma constituents in fermentation Lingtoudancong Oolong tea was studied by gas chromatography and mass spectrometry analysis. Results showed that deep fermentation Lingtoudancong tea possessed more kinds of aroma constituents than traditional fermentation Oolong tea. The traditional fermentation Lingtoudancong Oolong tea showed higher content of linalool, α-terpineol, indole and cis-Jasmone, but less Linalool oxide content than those of deep fermentation tea. The different of characteristic aroma constituents is due to the changed contents of linalool and linalool oxide in different plucking season. The tea plucked in autumn and spring showed lower content of linalool and linalool oxide (50.98~51.72%). But tea plucked in summer showed higher content of linalool and linalool oxide (more than 69.77%). The concentration of essential constituents such as nerolidol, jasmine, indole, 4-(2,4,4-Trimethyl-cyclohexa- 1,5-dienyl)-but-3-en-2-one andα-citral are higher in autumn tea than those in the other teas. The result of sensory evaluation showed that the autumn tea is better than the others.