Analysis of Grape Procyanidins and Proanthocyanidins

Another method for extraction and purification of tannins from grape seeds and skins was proposed by Vidal et al. (2003). For seeds 

4 dimer dimer digallate trimer trimer gallate tetramer 

5 trimer trimer gallate tetramer tetramer gallate pentamer 

6 trimer gallate trimer digallate tetramer tetramer gallate tetramer digallate pentamer pentamer gallate 

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