How Does the Wine Fermentation Process Happen?

How Does the Wine Fermentation Process Happen?

The wine fermentation process is accomplished by yeast converting grape juice into alcohol and carbon dioxide. Here are the basic steps:

1. Grape Harvest
Grapes are harvested at a certain level of ripeness depending on the type of wine and the desired flavor profile.

For white wine, grapes can be picked earlier, for red wine later.

2. Crushing and Pressing
For red wine: Grapes are crushed and fermented with their skins.

For white wine: After the grapes are crushed, the skins are removed and only the juice is fermented.

3. Fermentation Begins
Natural yeasts or selected cultured yeasts are added to the grape juice (must).

The yeast begins to convert the sugar in the grape juice into alcohol and carbon dioxide.

In red wines, regular stirring is done to remove color and tannins from the skins.

4. Fermentation Process
Temperature:

White wine: 10-15°C (slower, to preserve aromas).

Red wine: 22-30°C (faster, to extract tannins and colors).

The fermentation period usually lasts 1-3 weeks.

Carbon dioxide is released in the form of bubbles, indicating that the process is active.

5. Second (Malolactic) Fermentation (Optional)
In red wines, the apple acid is usually converted into softer lactic acid.

This process gives the wine a softer and creamier flavor profile.

6. Resting (Maturation) of the Wine
After fermentation is complete, the wine is separated from the lees and matured in steel tanks, oak barrels or bottles.

This process can take from a few months to a few years.

7. Filtering and Bottling
The wine is freed from the lees and filtered if necessary.

Before bottling, preservatives such as sulfur dioxide (SO₂) are added to protect against spoilage.

At the end of this process, the wine is ready to be consumed, gaining balanced taste, aroma and alcohol content. 🍷