The ageing time is basic to achieve a maximum quality. During the first months of fermentation and ageing, the aromas will be primary, the ones that come from the own fruit. When it reaches the 18 months approximately, the aromes are subjected to a change process where we can find some touch of fresh yeast. In longer ageings the product turns to autolisi notes (degradation of celular yeast's walls) and we achieve smocked and toasted notes, lactics or vegetables. Aromas very complex that makes a cava to have a very important and complex aroma.