Analyses of Aromatic Compounds in Dangui Oolong Tea with Simultaneous Distillation Extraction and GC-MS

The aromatic components in Dangui Oolong Tea were extracted with Simultaneous Distillation Extraction(SDE) and analyzed with gas chromatography-mass spectrometry(GC-MS). Results showed that the aromatic components in Dangui Oolong Tea were different obviously from which in green tea, write tea and black tea, although they were made from the same variety of tea leaves. The aromatic components in Dangui Oolong Tea were mainly alcohols(44.27%), esters(22.15%) and hydrocarbon compounds(12.29%); others were aldehydes(8.19%), ketones(3.98%) and nitrogenous compounds(3.28%), respectively. The composition of aromatic components between green, black and white tea were different, which were alcohols(54.62%), esters(18.92%)and hydrocarbon compounds(18.11%)in green tea; alcohols(47.78%), aldehydes(26.08%) and esters(11.07%)in black tea; alcohols(49.64%), aldehydes(17.25%%)and esters(11.12%)in white tea, respectively. The variety of aromatic compounds detected from Dangui Oolong tea were nerolidol(27.1%), Geraniol(4.04%), β-linalool, trans-linaloloxide(10.94%), 3-hexenyl ester(Z)-Hexanoic(1.25%), phenylacetaldehyde(6.01%), Benzaldehyde(0.81%), beta.-Ionone(2.78%), cis-Jasmone(0.57%), Butanoic acid, 3-methyl-, Indole(1.64%), 2-phenylethyl ester(2.47%),(Z)-3-Hexen-1-ol; 3-hexenyl ester(1.56%), Tetradecane(2.02%), Farnesen(15.63%)and so on. The data showed that the aromatic composition of Dangui Oolong tea was remarkably different from other Dangui teas.