Behind the Scenes: What Goes Into Making Cognac Casks

Like many alcoholic beverages, the casks used to make Louis XIII cognac are integral to the flavor and quality of the high-end cognac—and it sells for $3,600.
Louis XIII is remaking the giant "tiercons" for the next generation.
Courtesy of Louis XIII
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“Today, as cellar master of Louis XIII Cognac, I have to think a century ahead,” says Baptiste Loiseau of the iconic cognac brand. He wants the brand to last for the next generation—and for that reason, he’s made some serious decisions surrounding the materials used to produce the famed beverage.

The biggest decision? Recreating the essential tiercons, massive French oak casks, which have been used to age the eaux-de-vie (a French term that directly translates to “water of life”) for the cognac since its inception in 1874. The newest tiercon in the cellar is more than 100 years old, and it’s no easy task to build one. No one at the brand has ever completely remade them.

“The methods require unique and rigorous know-how, thanks to the transmission I had with my predecessor, Pierrette Trichet,” Loiseau says. “The precautions and expertise will contribute to the special features of Louis XIII.”

Baptiste Loiseau, cellar master of Louis XIII Cognac.
Courtesy of Louis XIII

Like the production of many alcoholic beverages, the casks used to create Louis XIII cognac are integral to the flavor profile and quality of the high-end cognac. Cognac is a type of brandy, double-distilled wine made from specific grape varieties in Champagne, France, then aged in French oak barrels from one of two forests, Limousin and Tronçais. Louis XIII is a blend of 1,200 different eaux-de-vie, the raw brandy before aging, sourced entirely from the Grande Champagne cru of Cognac and left to settle for years in exclusively Limousin oak wood casks.

The casks are first filled with the youngest Grande Champagne eaux-de-vie and left to mature. Not only does the barrel impart flavor on the distilled wine, but the liquid actually helps season the wood too. Over time, the character of the oak becomes essential to the flavoring of the more high-end eaux-de-vie, allowing for richer flavors and aromas that go into the final blend of Cognac. For Louis XIII, that’s the complex fusion of earthy notes like myrrh, leather, and cigar box with fruity ones such as figs, plums, and passion fruit.

“They are filled during the maturation process and provide valuable benefits during the aging process,” Loiseau says of the tiercons. “The subtle but important exchange between the eaux-de-vie and the air over the years brings wonderful body to Louis XIII Cognac. Myriad aromas intertwine to create a magnificent final blend.”

Louis XIII has traditionally used casks made of Limousin oak, which have the right tannins and porosity for the aging of an eau-de-vie.
Courtesy of Louis XIII

Consistency is of utmost importance and what consumers have come to expect when they drop $3,650 on a 750-milliliter bottle. But when a brand like Louis XIII ages out of its tiercons—one of the few cognac makers that still use them—it can have a serious impact on the resulting flavor. To guard the brand’s reputation and quality, the master coopers have been slowly replacing staves, individual panels of wood in the barrels. “Our master coopers regularly have to sacrifice existing barrels to repair others,” Loiseau adds, noting that it’s no longer a sustainable fix. Now that they have exhausted the supply they are willing to give up, Loiseau and his team embarked on the careful and lengthy process of remaking the tiercons.

Plenty of people are involved in the project. Beyond Loiseau and his team, coopers are essential. These artisans shape and craft the final barrels from the wood with the help of hoop makers, who work the wood. Loiseau is also collaborating with the forest wardens of the Office National des Forêts as well as foresters, who are responsible for selecting the best oak trees in the Limousin forest.

“From the very beginning, the wide-grain pedunculate oak was sought out for the production of our tiercons,” Loiseau says. “This variety of oak has a large and open grain, which plays a role in how the eaux-de-vie aromas develop. It also contributes to more pronounced tannins, which suits the longer maturation process.”

For a long time, the brand had the staves replaced in the barrels, but now it’s time to completely rebuild them.
Courtesy of Louis XIII

There are a total of eight stages to make a tiercon, and each one is under strict control. For example, the wood planks are dried for three years to reach their aromatic potential before being shaped into staves for the barrels. Loiseau explains that the brand doesn’t want to change anything about the resulting cognac. Instead, the team “want to maintain the same emotion and aromatic profile” the beverage has had since its launch in the 19th century.

Loiseau is carefully following historical production methods and seeking out talented artisans to undertake the rebuilding process. “It might be the way we cut the tree into merrains (the French term for staves) or how we monitor the toasting of the cask—it has an impact on the flavor,” he says. “It is clearly teamwork.”

As in the production of many alcoholic beverages, the casks used to create Louis XIII cognac are integral to the flavor profile and quality of the high-end cognac.
Courtesy of Louis XIII

Loiseau credits the brand’s ownership under the duo of families behind Rémy Martin as one of the reasons he’s been granted the green light for such an extensive—and expensive—venture. “We can do this type of meaningful project because Louis XIII is part of a family group looking ahead for the next generation,” he says. “Louis XIII will still be there in 100 years.”

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