Vines and vinifications
The vine (of botanical genus « vitis ») is a plant of the ampelidae family. It grows mainly in warm or temperate regions and includes a large number of species, including vitis vinifera, which provides all the grape varieties used in Europe and particularly in Burgundy.
It is a climbing shrub whose main organs are the roots and the vine stock. The life of the vine begins at the end of winter, as soon as the first suns appear. According to Baggiolini, the vegetative cycle is broken down into 10 stages. Even more care is needed for the plant.
The wine-making process
It is the whole process of wine-making, mechanical, microbiological and biochemical. The quality of the wine depends on the quality of the harvest, the respect of strict hygiene rules, the terroir and the winemaking techniques.
The grapes must be transported quickly to the winery and the wine-making equipment is cleaned and checked (wooden barrels are watered to increase their watertightness). Vinification is made in several stages which vary according to the grape variety and the wine to be produced.
The white wine-making process
As opposed to red vinification, there is, in general, no destemming to favour the extraction of the juice, not maceration to limit the tannin and colour contributions not sought after in white wine. Key phase in white wine-making, the pre-fermentations operations (natural classification by the enzymes in the grapes, etc.) are decisive.
Pressing prevents the solid materials from remaining in contact with the juice for too long: reducing the risk of transmitting herbaceous odours and bitter flavours to the wine. Sulphating: SO2 (sulphur dioxide) selects the ferments, facilitates clarification and has an anti-oxidant action.
The settling of the must removes any astringency from the wine (with the elimination of plant parts) but can, in the case of a must hat has been too clarified, slow down the fermentation. The vats can be seeded 24 hours after filling, using the BIVB’s CY 3079 yeast. This is called yeasting.
During alcoholic fermentation, the sugars are transformed into ethyl alcohol, energy, CO2 and many other components that make up the richness of the future wine. Malolactic fermentation: this is the microbiological transformation (lactic bacteria) of malic acid into lactic acid which has the effect of de- acidifying and stabilizing the wine. Transfer consists of separating the clear wine from its lees. This operation can also oxygenate he wines. In Burgundy, wines are racked only two to three times.
Destemming separates the stalk from the logs (berries). The treading breaks the skin to release the pulp and the juice.
The next two steps are sulphating (if necessary) and yeasting (optional). After a vattig period of 1 to 3 weeks at 28-30°C, the polyphenolic substances of the wine film (tannins and anthocyanins) are extracted. This is called maceration.
The organoleptic characteristics are widely revealed from the beginning of this stage. Two operations are carried out after the fermentation: draining, at the end of maceration when the wine is no longer sweet. This is a free-run wine.
Source : BIVB