Evaluation of astringency of preparations with different degree of tannin polymerisation.

Sensory and chemical methods were used for the evaluation of astringency of preparations differing in the degree of tannin polymerisation: (1) preparation of green tea (monomers), (2) preparation of grape seeds (oligomers), and (3) tannin polymers from black chokeberry fruits. The sensory and chemical astringency of the preparations was found to be diversified and occurred in the following order: tannin polymers > preparation of green tea > preparation of grape seeds. Of six modified starches under study, only two were able to negligibly neutralise the astringency sensations of tannins.