Influência da origem da madeira de carvalho no envelhecimento de vinhos tintos

this work evaluates the incidences in red wines characteristics, of ageing in oak wood barrels of species from portuguese forests and from pensylvania forests. the technological assay consisted of red wine ageing in 4 barrels of portuguese oak wood and 4 barrels of american oak wood in two cooperative cellars: carvoeira and benfica do ribatejo. the control wine had ageing in bottles of 0.75 dm-3. all barrels had been supplied by the same cooperage with medium toast level. in the appreciation of the effect in red wines characteristics of ageing in barrels of oak wood of distinct species it was done the determination from general analysis and colour parameters and of the volatile composition of the wines. the sensorial characteristics of the wines had been evaluated. the variance analysis to the factors, species of oak wood and wine, was carrying out for the generality of the analysed parameters. the results show that the factors wine and species of oak wood are important in the definition of the colour and the transparency of the wines and contribute for alterations in their volatile composition. to point out that the control wine differentiates of the wines aged in oak wood for the existence, exclusively, in these last wines of the cis and trans isomers of a-metil-？-octalactone. the content in the cis isomer of this octalactone allows differentiating the wines aged in portuguese oak wood barrels from those aged in american oak wood barrels.