Study on the Flavor Components in Chinese Jasmine Black Tea

This study is aim to determine the major flavor components in jasmine black tea (two scenting) during scenting process. The main aroma components in the base tea are benzyl alcohol (17.73%), linalool (16.17%), benzyl acetate (7.10%), methyl anthranilate (3.40%), cis-3-hexenyl benzoate (2.88%) and benzaldehyde (2.23%). Results show that benzyl alcohol (23.77%), linalool (19.73%), benzyl acetate (18.66%), methyl salicylate (3.84%), methyl anthranilate (3.60%), cis-3-hexenyl benzoate (3.27%) and α-farnesene (2.05%) are the seven major volatile compounds of jasmine black tea. After two scenting rounds, the concentrations of the total volatile compounds were increased five-fold dozens of times in the jasmine black tea compared with the base tea. The main aroma components of jasmine black tea were absorbed from fresh Jasmine sambac flowers. Jasmine tea flavor index (JTF) was used to evaluate the jasmine black tea aroma quality. Black tea JTF index (two scenting rounds: 0.57; five scenting rounds: 1.2) is higher than the jasmine green tea (two scenting rounds: 0.42, 0.38, 0.5; five scenting rounds: 1.004), suggesting that jasmine black tea aroma quality is not lower than jasmine green tea. The total tea polyphenols, flavonoids, gallic acid, theobromine, caffeine content did not show significant difference (P>0.05) during scenting process; EGC, EGCG content decreased by 0.18%, 0.17%; ECG content increased by 0.09%.