Putting a Cork In It

Sparkling conversation in Oregon: Tirage liège

By Gail Oberst

Tirage liège is the French term for using a natural cork stopper during the secondary fermentation of sparkling wine production. Disciples of the method gathered recently to preach the gospel according to Amorim Cork’s research team, along with an enologist from Dom Perignon. Representatives of the Portuguese cork manufacturer and the prestigious Champagne maker wanted to inspire Oregon wine producers to adopt traditional sparkling methods, including tirage liège.

Crafting sparkling wine begins the same as with most wines: Grapes are harvested, pressed and fermented, then blended and bottled. But in traditional méthode champenoise, a secondary stage of fermentation occurs in the bottle, requiring a minimum aging on the lees. Most American sparkling winemakers seal their bottles during this second “tirage” stage with crown caps, which remain on the bottle through aging, riddling, disgorging and dosage.

However, in the secondary stage, some of the finest quality wines made use of the méthode champenoise, aging under cork instead of crown caps, until the lees are disgorged. This is known as tirage liège (French for “tirage cork”). After disgorgement, a fresh cork is added before the wire cage is attached to the finished bottle.

Using cork stoppers while sparkling wine ages on the lees produces distinct flavors and profiles. According to Francisco Campos, researcher for Amorim Cork, and Amine Ghanem, winemaker at Dom Perignon, recent innovations in cork agriculture and production also reduced imperfections in this organic process.

This spring, about 20 Oregon winemakers attended the symposium hosted at Ponzi Vineyards. They reviewed the latest research and innovations in production and farming cork aimed at bottling sparkling wine. Among those attending: Max Bruening and Julia Cresto, Ponzi Vineyards; Kate Payne Brown and Rachel Healow, Argyle Winery; Leah Lyon, King Estate Winery; Evan Rose, Stoller Family Estate; Katie Santora, Chehalem Winery; Andrew Davis, The Radiant Sparkling Wine Co. and Lytle-Barnett; Bryan Weil and Aaron Fox, Vinovate Custom Wine Services; Casey Cobble, Four Feathers Wine Services; Elaine Heide, The Allison Inn & Spa; and Kenny McMahon, Arabilis Winery.

The seminar took place as more Oregon wineries are adding sparkling wines to their production.

“The most recent census estimated sparkling wine sales accounted for nine percent of all cases of Oregon wine sold in 2023, up from four percent in 2022,” said Katie von Bargen, communications director for the Oregon Wine Board. “It’s a growing category for Oregon wine.”

In addition to Capos and Ghanem, Kenny McMahon of Arabilis, the first Oregon sparkling winemaker to use cork during the tirage liège stage, spoke to the group about his company’s methods (see “The (Bubble)Doctors Are In,” this issue).

Here are some findings reported by Ghanem and Capos:

• Innovations include two natural cork discs (2D) covering the area closest to the liquid, creates a low permeability and scalping, allowing sparkling wines to express a distinctive fruit and floral aromatic profile. Studies indicate the 2D discs maintain longer flavor profiles, compared to solid corks or aggregated corks, by allowing some, but not too much, oxygen exchange.
• Secondary fermentation with tirage corks allows for a different aroma and taste profile from crown capsule-fermented wines.
• Innovations in the Southern Portuguese cork forest farms have strengthened the organic product with genetic improvements, pest controls and fertilization.
• New manufacturing technology reduces undesired organic material from corks, improving sensory qualities, preventing cork taint while reducing volatile substances.

Combined, the variety of corks now available allow winemakers to match stoppers to the desired sparkling wine. Among influences:

• Control oxygen exposure during tirage, disgorging and aging.
• Maintain phenolic compounds in cork that contribute to antioxidant capacity and color stabilization in wines.
• Control volatile compounds (ethyl and camphor) during aging.
• Control of acids to influence bubble size and aftertaste.

How does all this impact Oregon winemakers? The state’s expanding market for sparkling wines made using traditional methods is attracting new actors to the stage. Yet, only about 10 percent of sparkling producers use cork.

Dom Perignon’s Ghanem said they were visiting Oregon wineries, attending dinners and presenting workshops to share innovations in cork and expand its use– specifically during the tirage liège phase– among sparkling winemakers.

Natural cork remains part of the magic of Dom Perignon, Ghanem said. “Cork’s ability to be elastic is important to us.” And, he added, it is important to maintaining the quality of sparkling’s future.

“Wine knowledge is meant to be shared. That’s why we’re here.”

Did you know?

Cork is the outer bark of an evergreen oak tree, Quercus suber, native to Southwest Europe and Northwest Africa. Tannins in cork are similar to those in oak wood.

Portugal is the world’s largest cork grower/producer.

Cork bark is stripped by hand from the tree, which regrows a new bark layer.

More than 5.5 million acres of cork forests grow in the Mediterranean basin.

Amorim, one of the world’s largest cork producers, manufactures 3 million natural corks daily, and 10 million cork discs for a total of 6 billion corks per year.

Gail Oberst has been a Northwest writer, editor and publisher for decades. Among her favorite gigs was business editor for the News-Register, and editor pro temp for three months for the Oregon Wine Press. Inspired by the OWP, she founded the Oregon Beer Growler with her family, later selling it to Oregon Lithoprint. She continues to edit and write a wide range of articles for magazines, and weekly and regional newspapers. Recently, she published her first fiction novel, Valkyrie Dance, available on Amazon, and is working on her second, San Souci. She lives with her husband, Michael Cairns, a retired ecologist, in Independence, Oregon. They have four grown children and seven grandchildren.