The first stage in making cognac is harvest of this year. Then comes the vinification, a precise process that requires the greatest attention, and which we will focus on in this article.
But first, a quick reminder of the grape varieties used to make cognac, because this is where it all begins...
Cognac grape varieties
The Ugni-Blanc
The main grape variety used for cognac is Ugni-Blanc. Today, 98% of the Cognac vineyards are planted with this variety. But this variety is relatively recent and has not always been in the majority...
Folle Blanche
Before Ugni-Blanc, Folle Blanche was used! It was in the majority until the phylloxera crisis in the 1870s. Aphids ravaged the vines, destroying many hectares of plots, and it was for this reason that Folle Blanche was then put aside. Ugni-Blanc is much more resistant and gives better yields. Today, Folle Blanche accounts for 1% of the vineyard.
Ugni-Blanc and Folle Blanche are not the only grape varieties used to make cognac. We can also find Colombard, Montils and Semillon.
To produce quality cognacs and ensure good vinification, it is essential to monitor the ripeness of the grapes.
The maturity of the grapes
La phase de maturation, au mois de septembre, est la dernière phase avant les harvest of this year ! Cette étape doit être contrôlée de très près afin de produire des vins adaptés ensuite.
Elise, who is in charge of the production side of the estate, closely controls the ripeness of the grapes. She regularly takes samples of grapes from several bunches, at different exposures, to analyse their sugar content, acidity and therefore their ripeness. There has to be a good balance between sugar and acidity. We look for acidity because it helps to preserve the wine better, given that we don't add anything to our wines (no sulphites, for example). We also need to be vigilant, as some grape varieties can be more precocious than others. Folle Blanche and Sémillon are earlier ripening than Ugni Blanc and are very susceptible to rot. Regular checks are therefore essential.
Once the grapes have reached optimum ripeness, harvesting can begin. This generally lasts between 3 and 4 weeks. Then we come to the vinification stage!
Vinification in the Charente
Vinification involves transforming grape must into wine. In the case of cognac, this involves transforming white grape musts into rather acidic wines.
There are several steps to follow to ensure good vinification.
The stages in the winemaking process
The pressing process
The grapes are pressed directly after harvesting. This stage extracts all the juice from the grapes. It is carried out using discontinuous pneumatic presses, and, thanks to low pressure, a quality juice is obtained.
Alcoholic fermentation
Once the grape juice has been harvested, the alcoholic fermentation stage begins. The juice is placed in large stainless steel vats, then yeast is added. Thanks to these yeasts, after 5 to 6 days the sugars are transformed into alcohol and we obtain the white wine.
Wine characteristics for cognac
For the cognac, nous allons rechercher de l’acidité et non un côté trop sucré. En effet, les moûts de raisin doivent être d’un faible degré d’alcool potentiel (autour de 10% vol). Cela permet une acidité élevée et donc une meilleure conservation des vins. Détail important, pour la vinification charentaise, nous ne pouvons pas ajouter de sulfites ni de sucres pendant la fermentation. C’est pour cela que la présence d’acidité est importante.
Les vins pour l’élaboration du cognac sont donc des vins blancs acides qui ne sont pas dédiés à la consommation tel quel. Ces vins sont véritablement destinés à être distillés afin d’en extraire ensuite les meilleurs arômes.