
Napa Valley, CA 94558   Browse by a state...

The winemaking process
See more guides

Winemaking is not only an art, but also a science. It combines the process of fermentation with the creativity of the winemaker. The fermentation process starts when yeast is added to grape juice. The yeast consumes the grape's sugar and converts it to alcohol and carbon dioxide.

Each grape variety has its own identifiable characteristics. However, it is the winemaker who creates the style and personality of the finished wines. There is no fixed "recipe" for making certain wines, only general guidelines.

Winemaking Harvest


Harvest time is the defining moment in the winemaking process. Grapes are harvested during the cool morning hours and moved to the winery in open bins.



Manual harvesting is the hand-picking of grape clusters from the grapevines. In the United States, grapes are traditionally picked into 30 pound boxes, and in many cases these boxes are consolidated into ½ ton bins or two-ton bins for transport to the winery. Manual harvesting has the advantage of using knowledgeable labor to not only pick the ripe clusters but also to leave behind the clusters that are not ripe or contain bunch rot or other defects. This can be an effective first line of defense to prevent inferior quality fruit from contaminating a lot or tank of wine.

Winemaking Destemming and Crusher

Destemming and Crusher

Grapes are transferred to a stemmer/crusher where the stems are removed and the grapes are crushed. Some grapes may bypass the stemmer/crusher and go directly to the press for whole berry pressing.



Winemaking Fermentation


After crushing and de-stemming, the juice from the grapes is put into the fermentation vats, where alcoholic fermentation takes place (the conversion of sugar into alcohol and CO2). During the fermentation and aging process, which takes three(3) to six(6) months, the fermentation continues very slowly. The wine is kept under an airlock to protect the wine from oxidation. Proteins from the grape are broken down and the remaining yeast cells and other fine particles from the grapes are allowed to settle. Potassium bitartrate will also precipitate, a process which can be enhanced by cold stabilization to prevent the appearance of (harmless) tartrate crystals after bottling. The result of these processes is that the originally cloudy wine becomes clear. The wine can be racked during this process to remove the lees.


Winemaking Ageing/Racking


After fermentation, the wine is transferred or "racked" into a different vessel. In some instances, the wine is aged in stainless steel tanks. In other instances, the wine is put into oak barrels where it will continue its development until bottling. After barrel ageing and prior to bottling, the wines are fined and filtered to help stabilize and clarify them.


This is the last stage before the slow and relatively lengthy ageing process. Wines are bottled in a sterile environment, and sealed with a cork.




Copyright © 2021 Savvy Wino. All rights reserved.