Cabernet Sauvignon aromatics

Murat, M. L., Tominaga, T., Dubourdieu, D. (2001a). Assessing, the aromatic potential of Cabernet Sauvignon and Merlot musts used to produce rose wine by assaying the cysteinylated precursor of 3-mercaptohexan-l-ol. J. Agric. Food Chem., 49, 5412-5417. 

Methods to measure cysteinylated aroma precursors in must were developed by Peyrot des Gachons et al. (2000) and Murat et al. (2001b). They allowed the location of thiol precursors to be determined in Sauvignon blanc grapes (Fig. 8B.7). Around 80% of P-4MSP is in the juice and 50% of P-3SH in the skin. The skin contact improves the must aromatic potential, but its main effect is on the P-3SH content (Fig. 8B.8). Similarly, in Cabernet Sauvignon and Merlot grapes, 60% of the P-3SH is located in the skins This method has been also applied to study the influence of... 

Arriagada-Carrazana, J.P., C. Saez-Navarrete, and E. Bordeu. 2005. Membrane filtration effects on aromatic and phenolic quality of Cabernet Sauvignon wines. J. Food Engirt. 68 363-368. 

Certain heterocyclic compounds are also important aromatic substances in wines, such as pyrazines in Cabernet Sauvignon and Sauvignon Blanc wines (see Section 8.2.11.1.7) and both enantiomers of 3-hydroxy-4,5-dimethyl-5if-furan-2-one (sotolon), which occur in white wines, sherries and are a key component of the typical aroma of aged Port wines. The precise chemical reactions leading to the formation of bouquet substances are not yet widely known. There are two types of reactions that produce bouquet constituents oxidation, which is characterised by the presence of aldehydes and acetals (e.g. in Madeira-type wines) and reduction (such as in quality table wines after a period of bottle maturation the flavour of low-quahty wines does not improve under the same conditions, but instead maturation often leads to a loss of freshness). During wine aging, glycosides of terpenic alcohols and... 

Climatic conditions evidently have an infiuence on all grape constituents—in particular, secondary metabolites such as phenohc compounds and aromatic substances. Studies on these substances are incomplete and have often been carried out with very different techniques—especially extraction. Table 10.9 gives an example of the phenohc composition of Cabernet Sauvignon grapes at the time of harvest for the 1983, 1984 and 1985 vintages. The skin anthocyanin content is higher in quality vintages. This relationship is not valid for tannins. 

Qnality cnltivars snch as Cabernet Sauvignon and Pinot Noir lose much of their aromatic substance and phenolic compound finesse in warm climates. Figme 10.22 indicates the phenological behavior diversity of these two varieties in the different viticultural regions of the world. In a warm climate, characterized by average monthly temperature always above 10°C (for example, Perth, Australia), the duration of development is particularly short—notably at maturation. Conversely, the cycle grows longer in cool and humid temperate climates (French vineyards and in Christchurch, New Zealand). 

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