Tannin-protein interactions

Drawing on this and the reported specificity of tannin-protein interactions ( ) leads to the conclusion that any useful in vitro modelling of the impact of tannins on digestion must consider more than pH and the concentrations of the buffer, enzyme, substrate, and tannin. The actual enzyme-substrate system must be nutritionally realistic to control for specificities of the reaction of tannins with proteins (including enzymes) gastrointestinal mucoproteins should perhaps also be included on the same grounds. Besides all this, misleading results nay still be obtained if bile surfactants are omitted from the equation. 

Edelmann, A. and Lendl, B., Toward the optical tongue flow-through sensing of tannin-protein interactions based on FTIR spectroscopy, J. Am. Chem. Soc., 124, 14741, 2002. 

Hagerman, A.E., Tannin-protein interactions, in Phenolic Compounds in Food and their Effects on Health I. Analysis, Occurrence, and Chemistry. ACS Symposium Series 506, Ho, C.T., Lee, C.Y., and Huang, M.T., Eds., American Chemical Society, Washington, DC, 1992, 236. 

Hagerman, A.E. and Klucher, K.M., Tannin-protein interactions, in Plant Flavonoids in Biology and Medicine Biochemical, Pharmacological, and Structure Activity Relationships, Middleton, E. and Harbome, J., Eds., Alan R. Liss, Inc., New York, 1996. 

Apart from salivary proteins, other proteins have been used in the tannin-protein interaction studies due to some characteristics that make them similar to PRPs, like casein, gelatin, polyproline (Jobstl et al. 2004 Calderon et al. 1968 Luck et al. 1994 Poncet-Legrand et al. 2006 Siebert et al. 1996). Although it is not a protein, the polymer polyvinylpolypyrrolidone as also been used in these studies (Hagerman and Butler 1981 Laborde et al. 2006). Recently, an electronic tongue based on protein-tannin interactions has been developed to measure astringency (Edelmann and Lendl 2002). Despite the unquestionable importance of all these works to understand the interaction between tannins and proteins, extrapolation to the real context of wine sensory should be done with care. 

Tannin-protein interactions depend on the characteristics of the tannins size, structure, charge, etc. These interactions increase with the degree of polymerization of the procyanidins (Asano et al., 1984 Ricardo da Silva et al., 1991 Cheynier et al., 1992) and also according to their galloylation... 

Verge, S. Richard, T Moreau, S. Richelme-David, S. Vercauteren, J. Prome, J.C. Monti, J.P. First observation of non-covalent complexes for a tannin-protein interaction model investigated by electrospray ionisation mass spectroscopy. Tetrahedron Lett. 

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