top of page

Fermentation Friday™: Happenings On The Crush Pad & Beyond

Cooking with wine: “The best way to execute French cooking is to get good and loaded and whack the hell out of a chicken. Bon appétit.” - Julia Child

Chateau Motelena


Winegrape harvesting begins in the vineyard, leading up to that day -walking the vine rows is important to the winemaking ecosystem. At night, especially in Sonoma and Napa, the evening’s fog carries the earthy feel along the flow, moving with the jet stream. It’s hard to explain, but a person can feel “Crush,”; it’s an innate state of being. We know it's time, even if we aren’t the farmers or vintners.

Optimal sun and placement are part of growing sweet grapes, matured by the sun to peak fruit. When it is time, anyone and everyone is up all night, examining every node to ensure a successful harvest. Once the grapes are put into a truck, they head to their county weights and measure scale for recording, then off to the crush pad! Municipal organizations track data at the “boots on the ground level” for the United States Department of Agriculture (USDA) and the state where the farm resides. That data is then sent to the USDA for collection and publishing. The winegrapes quickly leave the scales and head to the crush pad for destemming and juice extraction.

Crushing & Destemmer Technologies

By the time weights and measures pencil in the weight and estimated market values of the load, teams await the trucks in the dark of night on the Crush Pad. Everyone is on deck for crush; it’s like attending a Catholic Vigil Service on Christmas Eve. The church fills with community members to experience the connection it brings forth. Trucks gently release the load into bins, and the team runs them through the Destemmer - Crusher. It’s a combination system that gently removes the berries (winegrapes) from the stems. The stems are full of tannins, and to yield the liquid gold from the berries, the system gently separates the less desirable matter from the fruit and runs it through to a crusher downstream.

Berries - Bunches Destemmer

The team fires up the system and hand-feeds or drops with a front loader, the berries into the hopper on top, and they fall into a trommel, moving clockwise. The trommel rotates, and the de-stemmer system employs a steel shaft that moves counterclockwise with polyethylene fingertips to separate the berries from their host gently. The berries then drop through the trommel holes, and the steams are sloughed off into a composting barrel for chopping and future soil-making.

Winegrapes Harvest

The Process Of Fermentation

Once the grapes are crushed, they are deposited into a vat and off to the press. The fermentation process varies for red and white winegrapes, but the process flows are similar. Choosing the yeast fermentation times is an exacting science, and every winemaker has a specific formula and school of thought used to run the press, the type of yeast implemented, to barrel fermentation. Some winemakers have run settling tanks using sturgeon fish bladders to filter sediment and other impurities from their wine. Once the press is complete, the wine is sent to the settling tanks and then off to the vats for yeast and the malolactic (white wines) fermentation additives. The juice is contained and racked for a specified period of time for stabilization and fining.

Barrel Fermentation

Racking & Relocating

The cellar staff is responsible for managing racking through the process flows at least three times throughout the lifecycle of winemaking - sometimes more. It offers the juice an opportunity to breathe some oxygen, ridding the wine product of funky smells like sulfur and rotten eggs. The cellar staff uses a vacuum-based, positive displacement pump to move the wine from primary to secondary fermentation and then degassing. Winemakers use all or one of three types of pumps to move and rack wine: air/diaphragm pumps/centrifugal pumps/and positive displacement systems.

Wine Corks

Aging & Blending

If you’ve seen the movie Bottleshock circa 2008, you learned that white wines tend to brown during aging, and reds tend to lean toward amber or cherry red over time. The Wine Enthusiast does beautiful work on infographics and process flows. Wine blending is an art and a delicate science of percentages, estimations, and precise calculations. Most winemakers believe the earlier they blend, the more complex and others think waiting six months from processing is the right time to blend varietals. It takes a winemaker hundreds of attempts to get the right taste for the palate.

Wine Bottles


Bottling happens one of two ways: by hand or through automation at the plant. I was invited to a bottling party in Glen Ellen, California, several years ago. This family winery was large enough to sell wines by the case. Still, in the spirit of keeping it a community-based effort, the winemaker enlisted the help of friends and family during bottling. One year, I was out on the road and stopped in to see if they needed any pump equipment or motors, and I was invited to bottle. We showed up that next Saturday; it was a great experience and one I learned a lot from.

We hauled out 275 cases of empty bottles, hand-filling each one. Once filled and ready to move down the assembly line, we moved the bottles down to the people corking the bottles. Given that Spirits is a highly controlled industry, it is the responsibility of the owner to ensure the bottles are filled to the correct level. Corking is a push and load mechanism, while one cork is inserted, the other is teed up for the next. Once fully corked, the wine is put back into the cases and sent off for labeling just down the line. The owner’s wife is an artist who designed all the labels for each vintage.

Large wineries and bulk wine cooperatives manage the scales of a hundred thousand cases on a bottling line and employ up to 1000 people. The wine is pumped through a centrifugal or positive displacement pump via the tank to the bottle filler. This process helps with speed and timing in the workflow. Electrical controllers are programmed by cellar staff to manage each tollgate. Nitrogen applications are used during filling to avoid oxygen exposure and employ removal.



Pulling out the wine thief, the winemaker plunges the wine into a transparent receptacle, releasing their thumb from the air vent and pouring it into a glass for tasting. Barrel tastings are a culture in the wine valleys of California. It’s the only way winemakers taste daily to ensure aging and enological profiles. The profiles should be rich and round, with layers of fruit and oak. ⧫


18 views0 comments


Rated 0 out of 5 stars.
No ratings yet

Add a rating
bottom of page