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IVES 9 IVES Conference Series 9 Macrowine 9 Macrowine 2010 9 Chemistry, functionality and analysis of grape and wine macromolecules and secondary metabolites 9 Evaluation of methods used for the isolation and characterization of grape skin and seed, and wine tannins

Evaluation of methods used for the isolation and characterization of grape skin and seed, and wine tannins

Abstract

Validation of the phloroglucinolysis and RP-HPLC method showed selectivity and repeatability within acceptable limits for all investigated matrices. Recovery of polymeric phenols by SPE was also acceptable. Phloroglucinolysis on crude and purified tannin fractions was successful but in the case of grape seed tannin the results differed significantly (30 %). Generally, grape seed tannin extracts are not purified before phloroglucinolysis. These phenomena need to be investigated further.

Publication date: July 3, 2024

Issue: Macrowine 2010

Type: Article

Authors

Anita OBERHOLSTER, Lise-Marie CARSTENS, Erna H. WITBOOI

Department of Viticulture and Oenology, Stellenbosch University, Stellenbosch, ZA

Contact the author*

Keywords

phloroglucinolysis, tannins

Tags

IVES Conference Series | Macrowine | Macrowine 2010

Citation

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