How Is Wine Made?

Harvest

Getting fruit from the vineyard to the winery is the first step in the winemaking process. However, there are more decisions to be made here than you may think. First and foremost, choosing the ideal picking date is crucial. Winemakers regularly taste fruit from their vineyards throughout the year to assess acidity and sugar levels. When the time is deemed right, teams are gathered and sent out into the vines to collect the fruit. 

Harvesting can be done one of two ways: either by hand or by machine. The former takes longer, though allows for more quality control and sorting in the vineyard (if desired). The latter is generally done at larger estates that have more ground to cover.

Crushing/Pressing the Grapes

This step is slightly different, depending on whether white, rosé, or orange or red wines are being made. First and foremost, if the winemaker desires, the grape berries are removed from their stems using a destemmer. Crushing follows. For white wines, fruit is generally crushed and pressed, meaning that juice is quickly removed from contact with the grape skins. Once pressed, the juice is then moved into a tank to settle, then racked off of the sediment. 

For orange and red wines, the fruit is crushed (with or without stems) and left on the skins for a given period of time to macerate. This is what ultimately gives red and orange wines their color and tannin structure. 

Fermentation

The equation of alcoholic fermentation is simple: Yeast plus sugar equals alcohol and CO2. Fermentations can be done with either native yeasts or cultivated yeasts. Native yeast fermentations (or spontaneous fermentations) are executed with naturally present yeasts found on grape skins and in a winery’s environment. Cultivated yeast fermentations are implemented by using purchased strains of yeast and adding them to the juice to execute the process. Spontaneous fermentations tend to take much longer and are often credited with producing more complex final wines.

Aging

Several factors come into consideration when developing a wine’s aging (or élevage) regimen. First, the vessel decision is the big factor. Most winemakers will choose to age their wines in steel, cement or oak, although terra cotta or clay, glass and other vessels are also possible options.

Aging wine in steel creates a nonoxidative environment, meaning that wines are not exposed to oxygen. This tends to preserve fresh fruit-driven flavors in the wine, and no external tannins or flavor are added from wood. On the opposite side of the spectrum, oak aging creates an oxidative environment, meaning that the wine has contact with oxygen. This allows the wine to develop different levels of texture and flavors. When new oak (as opposed to neutral or used wood) is used, flavors of vanilla, baking spice, coconut and/or dill can often be tasted in the resulting wine.

Fining and/or Filtering the Wine

Post-aging, some winemakers will choose to fine and/or filter their wines to remove any residual sediment from the juice. Filtering is done through a porous material, whereas fining requires adding some sort of substance to the wine (generally bentonite, egg whites, gelatin or isinglass) to the wine and allowing the sediment to coagulate. Note that residual sediment in wine is absolutely harmless and is completely OK to drink. Winemakers who choose to fine and/or filter their wines generally only do these steps for aesthetic reasons.

Bottling

Once the wines are aged and fined and/or filtered, the wine is ultimately bottled and ready to be packaged. Some winemakers choose to additionally age their wines in the bottle for a given period of time prior to releasing them. Once bottled, the wines are labeled and sealed, with corks, screw caps or other closures, and are sent off to be delivered to your local watering hole or neighborhood retail shop.