Chapter 8A
Wine Aroma Precursors
Raymond Baumes
Contents
8A.1 Introduction...................... ........................................ 251
8A.2 UnsaturatedFattyAcids.................................................... 252
8A.3 PhenolicAcids............................................................ 253
8A.4 Carotenoids .............................................................. 255
8A.5 Glycoconjugates .......................................................... 257
8A.6 S-CysteineConjugates ..................................................... 260
8A.7 Precursors ofDimethylsulfide ............................................... 263
References ............................................................... 265
8A.1 Introduction
The aroma precursors herein describedare non-volatile grape aroma precursors
recognized to be related to the wine aroma varietal character. Indeed, grapes of
mostVitis viniferacultivars used in winemaking have no characteristic aroma, with
a few exceptions, such as monoterpenoids in Muscat cultivars and some other aro-
matic cultivars, and 2-alkyl-3-methoxypyrazines in Cabernet-Sauvignon and related
cultivars (Bayonove 1998). However, these grapes contain different groups of non
volatile aroma precursors: unsaturated lipids, phenolic acids, carotenoids,S-cysteine
conjugates, glycoconjugates andS-methylmethionine. These non-volatile, odorless
constituents are susceptible to transformation into volatile varietal aroma com-
pounds during the biotechnological sequence of wine, from the cellular disorga-
nization of grape berries during harvest to the maturation of wine during its storage
(Fig. 8A.1). They are generally secondarymetabolites under genetic control, some
of them associated with specific cultivars, but they are also dependent on the several
factors which define the “terroir,” e.g. situation, soil, climate, viticultural practices.
However, this chapter includes neither the main carbon, nitrogen and sulfur
substrates of yeasts, giving rise to the volatile secondary products of alcoholic
R. Baumes (B)
UMR Sciences pour l’Oenologie, 2 place Viala – 34060 Montpellier Cedex, France
e-mail: [email protected]
M.V. Moreno-Arribas, M.C. Polo (eds.),Wine Chemistry and Biochemistry,
DOI 10.1007/978-0-387-74118-511,©CSpringer Science+Business Media, LLC 2009
251