Harvest happened. 101 winemaking
I started this blog with high ambitions of posting weekly throughout the harvest, but well, that obviously did not happen... After 11 hour days/ 6 days a week, one has little motivation to write about what they’ve just been doing. That said, I have just finished my final “décuvage” so the long days are but a memory and only positive thoughts from harvest fill my thoughts.
Here’s a quick overview of the last 1.5 months in a nutshell… a general red-wine making lesson.
Harvest of grapes
When to harvest the grapes is the most important decision the winemaker makes each year. One bases this decision on the grapes' sugar maturity, phenolic maturity, aromatic maturity, acidity, and disease pressures. For example, to make sure rot, such as Botritytis, doesn't ruin the crop, the winemaker must look toward the weather report and might be forced to start picking earlier than ideal. With experience, the winemaker tastes the berries daily leading up to harvest and makes predictions about the potential resulting wine. Depending on the objectives of the winery, the grapes are either manually picked or mechanically picked.
Reception
A truck brings all of the harvested grapes to the reception area just outside of the winery and based on the size of the winery, there is a team of 1-20 people there. At wineries focusing on low-production and high-quality wines, there are 10+ people dedicated to just sorting out berries; i.e. making sure its only good berries going into the wine. Then, the berries are de-stemmed, optically- sorted (rare; very expensive), and finally, crushed.
Putting into cuves
After crushing the grapes, it is time to put them into cuves/vats. At the Chateau that I worked for this year, the grapes are put into the cuves by gravity. If wineries don’t use gravity, they use high-pressure pumps to transfer the crushed grapes to the vats. At most wineries, the wine is then sulfited and innoculated with yeast to kick-start the alcoholic fermentation (AF). That said, some wineries choose the more natural (though some would argue- risky) approach, using an indigenous yeast fermentation (wild yeast that is naturally found on grape skins), thus not inoculating with the Activated Dried Yeasts.
Pumping overs/ Push-downs
Depending on the varietal, and region of the world, pumping overs and push-downs are both used to homogenize the juice pre-fermentation and during alcoholic fermentation (AF). Generally pumping overs are more common in Bordeaux, whereas push-downs are more common in Burgundy. These techniques enhance the extraction of polyphenols, specifically anthocyanins (color compound) and tannins (complex, astringent compounds that can have wildly different gustative properties and Molecular Weights between 500 – 20,000) from the grape skins.
Décuvage:
After alcoholic fermentation, the free run and pressed wines are separated. The free run is first put into barrels or into another vat. Then a worker gets into the vat and shovels all of the grape skins and seeds into a cage, that will then be pressed to extract more wine.
Putting into Barrels
After racking and clarification, the wine is then put into barrels. Depending on the goal of the final wine, the wine will be separated into new & older oak barrels from different producers from all over the world. If the wine hasn’t finished Malolactic Fermentation (MLF) naturally, the winemaker might inoculate the wine with lactic bacteria. Lactic bacteria will then degrade the high amounts of malic acid in the wine into the less aggressive lactic acid.
Other Notes
All this occurs while taking daily density and temperature readings, quality control analyses, and daily tastings to make sure the wine’s progress is on track and that everything is microbially stable.
There you have it - Winemaking 101. Obviously, this varies wildly from winery to winery but those are the very basics of traditional winemaking.
