Tea has a unique fresh aroma. The aroma that the tea leaves give off comes across in the tea infusion. This fragrance is also referred to as the ‘nose’ of the tea.
It is generally believed that the characteristic of various kinds of tea consist of a balance of very complicated mixtures of aroma compounds in tea.
Aromas of compounds differ according to the variety of tea, and more than six hundred different aroma compounds are found in tea.
It is quite clear that the aroma of the fermented tea has to be quite different from the aroma of green tea.
Tea leaves contain a volatile oil consisting of alcohols, aldehydes, phenols and some fatty acids.
Fresh tea leaves have a somewhat grassy smell, and the refreshing fragrances of young leaves and flower similar to lily of the valley and rose are apparent.
Some of aroma compounds identified in fresh tea leaves are mostly alcohols, including Z-2-penten-1-0l, n-hexanol, Z-3-hexen-1-ol, E-2-hexen-1-ol and linalool plus its oxides, nerol, geraniol, benzylalcohol, 2-phenylethanol, and nerolidol.
The aroma of Japanese green tea, especially first crops of spring, is characteristically refreshing with a green note caused by (Z)-3-hexenyl-(E)-2-hexenoate and hexenoate.
Main aroma components of black tea are alcoholic comp sounds such as linalool, linalool oxides, geraniol, benzyl alcohol, 2-phenylethanol, while in oolong tea, jasmine lactone, nerolidol and indole are the most abundant aroma component.
Linalool and its oxidized derivatives namely linalool oxides are the main constituents of black tea aroma. In some aroma Assam black tea, the content is as high as 60%.
Important chemical compounds of aroma in tea leaves
