It seems that everything old is new again for boutique wineries: gravity feed, no yeast inoculation, fermenting in wood vats or concrete—and, now, basket presses.

“It is ironic, is it not?” said Randy Ullom, the head of winemaking for Kendall-Jackson. “We use them everywhere. We are even testing cement tanks. It’s all quite old fashioned.”

Ullom added, “Basket presses are quite gentle. We use them for blended reds and Pinot Noir.”

He said that press manufacturers have developed excellent automatic systems for applying pressure and made the presses easier to clean. Most use stainless steel rather than the wood slats of old presses, for example.

Stainless steel baskets also allow wineries to use the press for both red and white wines, if desired, though most winemakers interviewed don’t use basket presses for white wines.

Ullom said there is a loss of yield compared to membrane presses, but that is more than compensated by the quality and usefulness of the press.

K-J isn’t alone. Many leading winemakers use basket presses, and others have developed ways to have membrane presses mimic the action of traditional basket presses.

A summary of advantages
Anita Oberholster, the cooperative extension specialist in enology at the Department of Viticulture and Enology at the University of California, Davis, summarized the appeal of modern stainless-steel, large-volume basket presses while admitting there are no real metrics available comparing them to other presses.

“Several winemakers prefer a basket press for their premium wines.…They feel the wines have less solids and extract less of the bitter, rougher phenolics. This leads to fewer steps for clarification, preserving positive aroma profiles and a finer and softer tannin profile due to less phenolic extraction,” she said.

However, this is all based on general feedback from winemakers with no rigorous research. “Scientifically this could possibly be due to the fact that the basket press is a softer press than even the bladder press, resulting in less damage to seeds and thus less extraction from them.”

She explained, “Seeds contain more low-molecular-weight phenolics compared to the skin tannin. These low-molecular-weight phenolics and tannins have a higher bitter-to-astringency ratio than the large-molecular-weight tannins in the skins. Higher contribution of skin tannins to wine tannins have been correlated with a softer mouthfeel and finer tannin perception.”

She added, “There seems a loss of 5%-10% yield using the basket press compared to the bladder press, indicating softer pressing but also lower efficiency. Conversely, the basket press seems to be quicker compared to horizontal presses due to the larger drainage surface.”

Reports from winemakers
Mario Monticelli is the winemaker for Trinchero Napa Valley, the Trinchero family’s high-end winery in St. Helena, Calif. He formerly worked with renowned winemaker Philippe Melka on such high-end wines as Vineyard 29 and Quintessa.

Monticelli uses a Bucher Vaslin basket press for all his red wines, which sell for up to $95. “We use the free-run juice and evaluate the lightly pressed juice. The hard press is shipped out” to other wineries including the company’s second line, Napa Cellars.

He says the must has always gone dry by the time he presses it, typically after 20 to 35 days.

He gets about 130 gallons per ton from the press (including free-run, of course.) “We could get 20-30 gallons more with a bladder press, but that’s not important for us for these wines. Quality is the priority.”

Monticelli doesn’t use the basket press for whites. “We’d get far lower yields,” he said. For white winegrapes, he uses a bladder press at another winery location.

Charles Thomas, winemaker at Quintessa in Napa Valley, Calif., has two basket presses. One is a larger Bucher Vaslin JLB. “We see both better yield and quality as long as we handle the grapes gently. If you do this, you’re less likely to get excess tannins and excessive solids.”

He said that the single direction of pressing and lack of shearing from tumbling seems to reduce solids and tannins.

Like others interviewed, Thomas has fully automated controls on the presses. He also ferments to dryness before pressing and uses a cycle time of less than an hour. He admits that he gives up a few gallons per ton of heavy press juice but he doesn’t use that anyway.

Like Monticelli, Thomas presses his whites (Sauvignon Blanc) elsewhere with a membrane press. “I tried it with whites once, and it was a big pain. You can place the berries in a nylon basket, but it’s easier to use a bladder press for them.”

Thomas finds it best to simply dump grapes into the basket from above rather than shoveling them in. “Get the gate on the tank higher than the basket,” he advised. Alternately, an elevator conveyor is the best approach.

Experience in Walla Walla
Gilles Nicault, the winemaker at Long Shadows in Walla Walla, Wash., uses a Diemme 23 basket press for all of the red wine produced at the winery, which has many famed winemaker partners. Nicault said that two partners, Melka and John Duval, recommended he get the basket press.

Nicault can operate the press either manually or automatically; it uses hydraulic pressure. “It presses and releases in cycles and has a sensor so it won’t press too hard. It’s very gentle,” he said. “By comparison, every time you press in a membrane press, you get dirtier juice. The grapes in the basket press help filter the juice.”

It’s difficult to compare the output from basket and membrane presses, Nicault said, since you have to let the solids settle out of the membrane-pressed wine. “Even so, the yield isn’t as high, but you can apply 6 bar of pressure compared to only 1.6 bar on a membrane press.” He added, “I could extract every drop, but I don’t want to do that.”

A full cycle takes about 1.5 hours. Nicault keeps the free-run juice separate from various fractions of the press wines and evaluates each separately. Some he uses for a second label, Nine Hats, referring to the nine winemakers who are partners in the Long Shadows venture.

Nicault uses a membrane press for Riesling. “It’s very difficult to press whole clusters like we use for Riesling in a basket press,” he stated.

Another artisan winemaker who uses a basket press is Darice Spinelli at Far Niente in the Napa Valley. She has both basket and membrane presses and has the chance to compare them. “The basket press isn’t useful for whites,” she stated. “We don’t destem the grapes, so we can only get about 2 tons of grapes into the 5-ton press.”

She uses the basket press for Cabernet and Merlot but finds it doesn’t do as well for larger berries with thin skins like Zinfandel and Syrah. “Pockets of grapes in the middle never break apart,” she complained.

She “definitely” finds fewer solids with the basket press due to lack of tumbling. “The juice from the membrane press is a little more subdued and earthy.”

She finds the juice has excellent fruit flavor. “I like the character of the press wine. It’s cleaner, brighter fruit. It depends on the year, but I can often add it back to the overall blend.” That can be an advantage in a light year when they need more wine.

On the other hand, she said that yields are much lower, even if you compare the output to settled juice from a membrane press. In some cases, if a lot of grapes come in at once, she has to use the bladder press as well as the basket press. “The basket press can only handle 5 tons, while the bladder press can take 18 tons.”

No need for a basket press?
Some winemakers have developed ways to obtain the advantages of basket presses using membrane presses.

Doug Fletcher, who supervises winemaking for Terlato Wine Group, which includes Chimney Rock and Rutherford Hill in Napa Valley, Sanford in Santa Barbara and Alderbrook in Sonoma County, worked with press manufacturer Diemme to do this. The press program applies pressure in steps, delaying application of the next pulse until the must is expelled. They also can avoid the tumbling action that is felt to rough up berries and seeds and extract more solids.

Stephanie Putnam, winemaker for Raymond Vineyards in Napa Valley, is another who takes this approach: “We don’t have a basket press at the winery right now.  What we do is mimic a basket press with our bladder presses, which essentially gets us exactly what we’re looking for—more gentle squeezing without any turning of the press.” 

She added, “From what I understand, those who have basket presses feel that the quality of the ‘press fractions’ is much higher with less bitterness, so it allows them to use more of the press fractions versus a normal press.” 

She added, “For bladder presses, the big improvement is the creation of what they call ‘stepping’ functions that allow the winemakers to manipulate the programs to keep constant pressure and remove tumbling sequences,
if desired.”

“We do press fractions on our bladder presses, and the characteristics of the year dictate how we use them. Sometimes the press wine is quite nice and with a little fining is useable for our other programs.”

Some other winemakers don’t see what the fuss is about. They don’t use presses for their better wines. Jason Exposto of Futo Wines has a basket press, but he doesn’t use it for his high-end wines (though he does use it to extract press wine for other purposes.) “It’s not part of our program,” he said, though he has found a basket press to be excellent for other tasks such as dessert wines that he’s made elsewhere.

Doug Fletcher goes even further. “I haven’t used press wine in our top wines for years,” he said. “We just use the free-run juice.”