What Comes After Picking?

Fall is officially here, and in wine country it is accompanied by the harvest season. For winemakers it’s an exhausting and stressful time because the work doesn’t stop after picking is complete.

First, the timing of picking the grapes is one of the most intense and unnerving times for grape growers. Pick too soon and risk underripe grapes, wait too late and risk destructive weather changes. Many grape growers determine when to pick by measuring the Brix, which is the sugar level in the grape which determines the potential alcohol percentage of the final wine. The higher the sugar, the higher the alcohol potential in the wine.

Other winemakers measure the acid or pH level in the grapes to decide when they are ripe enough.

And still others, pick by the taste profile they desire, which is something that requires many years of experience because they’re predicting how the taste and tannin in the grapes at the time of picking will produce the intended style of wine in the end product.

Grapes need to be picked when temperatures are cool for many reasons. As the temperature rises grapes are more likely to burst open which puts them at risk for oxidation and spoiling. This is why picking often starts in the middle of the night or early morning before the sun rises, especially in warmer climates like Sonoma and Napa.

Additionally, since grapes must then be transported to the winery or crushing facility, winemakers also need to account for the time the grapes will be in a vehicle and potentially exposed to warmer temperatures.

Once grapes arrive to the winery or crushing facility, they are usually sorted and MOG is removed, which refers to material other than grapes like twigs, leaves and bugs.

I was able to experience sorting a couple years ago at a friend’s winery as you can see in the photo below.

After sorting, grapes used to make white wine are typically destemmed, crushed and pressed immediately, so that the juice and skins do not spend time together. Whereas grapes for making red wine will be destemmed and crushed, but then the grapes skins, juice and seeds, which is called the must, will be left to macerate for a certain period of time before being pressed. This is one of the junctures in the process where each winemaker’s artistic and unique touch impacts the final wine. Some will allow only a few days of maceration and others will extend it into fermentation. The amount of time they choose is influenced by grape variety, as well as how much color and tannin the winemaker wants to extract.

Regardless of the type of grapes and the process chosen, the next several days is a critical time. The winemaker and the cellar masters and staff will be closely monitoring the temperatures of the juice and gently overseeing either manual or machine stirring of the must, which can be carried out many ways.

Once the fermentation process has finished, red wines will be pressed if they weren’t before. Then the winemaker chooses how to begin the aging process of the wines. Often red wines are moved into barrels and white wines may move into barrel, clay or stainless-steel tanks depending on the style of wine being made and again, this is the winemaker’s artistry more than science. Some may choose to put a portion in barrel and a portion in stainless-steel and then blend them after aging.

All wines will be left to age for a few months, even light body white wines like Sauvignon Blanc will spend at least six months aging before being bottled. Many red wines will spend a minimum of 12 months, but usually longer before being bottled.

Lastly, many winemakers will continue to age wines in the bottle before releasing them. For instance, in Spain, wines labeled Reserva must spend a minimum of 36 months for total aging time, 12 of which must be in barrel. The United States doesn’t have laws like this, so it’s the winemakers choice of how long to hold on to a vintage before releasing it.

Of course, there are multitude of additional steps carried out to create the intended style and quality of wine the winemaker seeks, but we can’t divulge all their secrets;)