The early ripe mangosteen was used for tannin extraction. The factors affecting tannin extraction such
as size of the mangosteen peels, solvent types, temperature, extraction period and the ratio of mangosteen peel
to solvent were studied. Extraction of the mangosteen peel sized 20/30 mesh with the mixture of water and
95% ethanol (1:1 v/v) at 80o
C for 2 hours and the ratio of mangosteen peel to solvent of 1:10 (w/v) gave the
highest yield of tannin. The crude extracted tannin was purified by adsorption chromatography on Sephadex
LH-20. The recovery yield of the purified tannin was 27.48% of the total tannin. The chemical test results of
the purified tannin showed that the condensed tannin was the predominant type of tannin in mangosteen peel.
Since the condensed tannin can be applied to precipitate protein, the purified tannin obtained from the
experiment was then used for protein precipitation in wine. The results from the consumer test showed that the
wine clarity and the increasing of the wineûs astringency were noticeable at 95% significance level.