Tannin Concentration of Gyrinops Tea from Leaves of Juvenile and Mature Agarwood Trees (Gyrinops versteegii Gilg (Domke)) with Different Processing Methods

I Gde Adi Suryawan Wangiyana,

Abstract

Gyrinops tea made from leaves of agarwood (G. versteegii) trees endemic of Lombok Island can be an alternative product to optimize cultivation of G. versteegii in Lombok, Indonesia, because it could give continuing income for agarwood farmers during the long waiting period for the tree to produce agarwood. As new source of tea, G. versteegii leaves need to be investigated for it tannin content as a standard quality of tea. This study aimed to investigate tannin concentration of Gyrinops tea made from leaves of G. versteegii trees of different ages with different processing methods, by examining the effects of two different ages of the trees (1 or 5 years) and 4 methods of leaf processing (fresh leaves, dry leaves with no oxidation, dry leaves with 2 and 4 weeks of oxidation). The results indicated that Gyrinops tea made from leaves of older G. versteegii trees contains higher percentages of tannin than the tea made from leaves of the younger ones, and dry leaves contain higher percentages of tannin than fresh leaves, with a tendency of higher tannin concentration in leaves of longer duration of oxidation process, but only in leaves from older G. versteegii trees, while in the younger ones, there was no effects of oxidation duration.