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arXiv · 0810.1136

Colloidal stability of tannins: astringency, wine tasting and beyond

D. Zanchi·C. Poulain·P. Konarev·C. Tribet·D. I. Svergun
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Abstract

Tannin-tannin and tannin-protein interactions in water-ethanol solvent mixtures are studied in the context of red wine tasting. While tannin self-aggregation is relevant for visual aspect of wine tasting (limpidity and related colloidal phenomena), tannin affinities for salivary proline-rich proteins is fundamental for a wide spectrum of organoleptic properties related to astringency. Tannin-tannin interactions are analyzed in water-ethanol wine-like solvents and the precipitation map is constructed for a typical grape tannin. The interaction between tannins and human salivary proline-rich proteins (PRP) are investigated in the framework of the shell model for micellization, known for describing tannin-induced aggregation of beta-casein. Tannin-assisted micellization and compaction of proteins observed by SAXS are described quantitatively and discussed in the case of astringency.

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D. Zanchi, C. Poulain, P. Konarev, C. Tribet, D. I. Svergun. 2008-10-07. Colloidal stability of tannins: astringency, wine tasting and beyond. https://doi.org/10.1088/0953-8984%2F20%2F49%2F494224

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