Chapter 9D
Influence of Phenolics on Wine Organoleptic
Properties
Celestino Santos-Buelga and Victor de Freitas
Contents
9D.1 Introduction...................... ........................................ 529
9D.2 TheColorofRedWines.................................................... 530
9D.2.1 Origin and Components..... ........................................ 530
9D.2.2 Copigmentation ................................................... 531
9D.2.3 ChangesDuringWineMaturationandAging........................... 541
9D.3 Astringency .............................................................. 550
9D.3.1 AstringencyPerception ............................................. 550
9D.3.2 InteractionsBetweenProteinsandTannins............................. 551
9D.3.3 TanninStructuresandTheirInfluenceinWineAstringency ............... 554
9D.3.4 ProteinStructures.................................................. 555
9D.3.5 Changes in Tannin Composition and Astringency During Wine Aging ...... 556
9D.3.6 Polysaccharides and Astringency............................... ...... 557
9D.3.7 Experimental Studies of the Interactions Between Proteins and Tannins,
andAstringency....................................................559
References ............................................................... 560
9D.1 Introduction
In his reference paper about the polymeric nature of wine pigments published in
1971, Somers stated “the chemistry of wine phenolics, which entirely responsible for
wine colour and tannin character, is still largely a matter of speculation”. Although
relevant advances in the knowledge of the structures of wine pigments and tan-
nins and the reactions taking place during aging have been made since then, that
statement still applies. Many gaps still exist regarding the precise nature of the
compounds and mechanisms that determine red wine color expression and astrin-
gency perception and their changes during wine life. These aspects have not been
fully elucidated and their control continues basically as an empirical matter and still
constitutes “a major challenge in oenological research” (Somers 1971).
C. Santos-Buelga (B)
Unidad de Nutrici ́on y Bromatolog ́ıa, Facultad de Farmacia, Universidad de Salamanca, Campus
Miguel de Unamuno s/n, E-37007 Salamanca, Spain
e-mail: [email protected]
M.V. Moreno-Arribas, M.C. Polo (eds.),Wine Chemistry and Biochemistry,
DOI 10.1007/978-0-387-74118-520,©CSpringer Science+Business Media, LLC 2009
529