Aroma Composition of Vitis vinifera Cv. Tannat:  the Typical Red Wine from Uruguay

The free volatiles, as well as those released from the glycosidically bound forms by enzyme hydrolysis, have been analyzed to chracterize young Tannat wines from two successive vintages. The Tannat wine showed some aroma profile peculiarities detected in the free forms but, above all, in the bound fraction for the level and profile of the norisoprenoidic fraction. Among the free volatile compunds, a rather low content of C6 alcohols with a prevalence of cis-3-hexen-1-ol on the trans form and sometimes a remarkable level of trans-2-hexen-1-ol seem to be typical for the variety. C13-norisoprenoidic and monoterpenic volatiles made up ∼42% of the total level of the volatiles observed in the glycosidase enzyme-released fraction. The other volatiles were C6 alcohols (6%) and benzenoid compounds (51%). The dominating monoterpene alcohols were the cis and trans isomers of 3,7-dimethyl-1,6-octadiene-3,8-diol (8-hydroxylinalool). The C13-norisoprenoid pattern was composed by 3-hydroxy-β-damascone, 3-oxo-α-ionol, vomifoliol, 4-oxo-β-ionol, 3-oxo-7,8-dihydro-α-ionol, 4-oxo-7,8-dihydro-β-ionol, grasshopper ketone, and 7,8-dihydrovomifoliol. Keywords: Vitis vinifera cv. Tannat wine aroma; free and bound forms; monoterpenes; norisoprenoids; shikimate derivatives