How to Press Red Wine Grapes

Winemaker David Lecomte explains City Winery’s ventilation and lighting accessories used during the press as two teammates shovel out about 2 tons of pomace from a tank.

The City Winery team has been busy pressing wines for the past week or so.

Pressing occurs after primary fermentation, when a winemaker determines if the young wine has reached its full potential and is ready to be pressed.

In short, pressing takes place once a wine is dry — that is, the free run wine has no more sugars to be fermented.

There are two types of wines that are produced during this stage of winemaking:

  • Free run wine is the wine that runs freely from a tank once the valve is opened.
  • Press wine is the wine that is squeezed from the solids placed in a press. At City Winery, we press two rounds of wine: light press and hard press.

Take a look at the video above and the pictures below for a tutorial on how to press red wine grapes and let us know if you have questions in the comments below!

Lecomte bleeds the tank, removing all of the final liquid, which is known as free run wine.

The first step of pressing wine is bleeding the tank of all final liquid, also known as the free run wine.

Free run wine is generally the highest quality wine, as it is the most aromatically elegant and has the cleanest mouthfeel, as it does not have the cloudiness brought about by lees in press wine.

Lecomte opens the tank after the bleed.

After all of the free run wine is bled out, the tank is opened and all of the wet pomace — the grape skin, seeds and stems left in the tank — is removed.

If a good bleed is administered, a block of wet pomace will flow out when the tank is opened. If not, a fountain of juices will flow out — this could result in the loss of wine, as it could spew everywhere.

Lecomte and wine aficionado Henry Gonzalez shovel out the pomace.

Once the tank is opened, it is necessary for someone to enter the tank and shovel out the pomace. That person enters through the bottom of the tank, instead of the top of the tank, so that it is certain that he or she can get out of the tank again. As a result, a hole needs to be dug in the pomace so that he or she can enter.

At City Winery, we have a modest ventilation and lighting system set up so that the person inside can see and is able to breathe, given the large amount of carbon dioxide within the tank.

Assistant Winemaker Bill Anton carries the basket press to the crushpad using a forklift.

Once the pomace is shoveled into the basket press, it it transported with a forklift to the crushpad, where the press will take place.

Lecomte operates the press.

There are four types of wine presses — City Winery uses a basket press to press its red wines. Wikipedia explains the basket press quite eloquently:

“A basket press consists of a large basket that is filled with the [fermented] grapes. Pressure is applied through a plate that is forced down onto the fruit. The mechanism to lower the plate is often either a screw or a hydraulic device. The juice flows through openings in the basket. The basket style press was the first type of mechanized press to be developed, and its basic design has not changed in nearly 1000 years.”

A hydraulic piston applies pressure to the fruit, pressing out juices.

City Winery sets its press for two pressure points during the press: a light press and a hard press.

The light press and hard press wines, as well as the free run wines, are all kept separate, because they generally have very different taste profiles.

The light press, or “first press” wine, flows outside the press.

Free run wine is fruity and aromatic, and as you press deeper into the fruit, the resulting press wines have increased tannins and mouthfeel.

Press wines are generally put back into the tank to ferment, because they contain residual sugars that need to be fermented. Typically press wines 1 to 0 Brix (the U.S. unit for Specific Gravity) — wines are “dry” (no sugar) at -1 to -2 Brix. This final fermentation process takes a few days to complete. The winery team closely watches the end of the fermentation stage and can warm up the tank to help the existing yeast finish the fermentation.

When both the free run and press wines are dry (without sugars), they are tasted separately, and the winemaker decides if he’d like to keep the three varied wines separate or blend them.

When free run wine is well-balanced, the winemaker keeps it separate. If the tannins are too tight or the wine has a light mid-palate, though, the press wine is usually blended in.

The decision on whether to blend or not is “based uniquely on the taste of the wine,” says Winemaker David Lecomte. He noted that from a practical point of view, it would make sense to blend all of the wines together, so that his team wouldn’t have to track the wines in separate lots.

However, the focus is on making the best wines possible, so blending is based on taste, not logistics. In a case where the team is unsure of whether there is an interest in blending back the press wines with the free run, they run a blind tasting, as not to be influenced by the practicalities of running a winery.

The likelihood of blending often depends on the varietal, Lecomte noted. With Cabernet Sauvignon, he often ends up blending the light press back, because a light mouthfeel can be problematic, as he’s going for a dark fruit and jam feel.

With Pinot Noir, the emphasis is on aromatic freshness and elegance, though, and the varietal can show beautifully without a long finish or mouthfeel — as a result, the press wine is usually not blended back in.

Cellar Hand Sikou Nikate and wine aficionado Lane remove the dry pomace from the press.

When all of the pressing is finished, the dry pomace remaining is the press is removed and disposed of.

And voila, you’re closer to a finished wine product!

Images courtesy of Hank Smeal, cellar intern