“It softens the harshness of the alcohol,” explains Miguel Lancha, cocktail innovator (yes, that’s really his title) for all the José Andrés properties. The aging time within the airtight leather bag also serves to bond together the ingredients, he says. “It becomes like a whole new drink.”
But bota bags aren’t the only way to infuse a drink with leather—sometimes the leather goes directly into the drink. For example, at NYC’s Saxon and Parole, leather bitters go into the on-tap Manhattan. And at Kings Biergarten in Houston, leather-infused whiskey is a key ingredient in the Lederhosen Smash.
“All of our servers wear lederhosen [traditional breeches made of leather],” explains Philipp Sitter, president of Kings Biergarten and the forthcoming Kings Bierhaus. “The concept was, ‘What if I took lederhosen and stuck it in whiskey?’”
He started by researching whether leather was even edible, and found that chemicals used to tan leather likely weren’t safe to consume. (Unfortunately, Norseman Distillery, a craft spirits producer in Minneapolis, didn’t arrive at the same conclusion; state regulators have demanded that Norseman stop selling its popular leather-aged aquavit because it was made with nonfood-grade leather.)
Sitter, meanwhile, honed in on vegetable-tanned calfskin, which is made using bark oils and other vegetable extracts. “That’s what they do with the baby shoes that are made out of leather,” Sitter notes. “Because babies are notorious for sticking their feet in their mouth and chewing on their shoes.”
Although the leather-infused whiskey is “just awful” served straight (the general consensus across the board is that you don’t want to do shots of leathered booze—it can be bitingly dry and not particularly tasty), Sitter found that it worked well when mixed with other ingredients. The final drink, the Lederhosen Smash, mixes lemon, simple syrup, fresh mint and cucumber with the leather-infused whiskey, which adds just a bit of its tanned flavor to the finish.
“We describe it as the way a new car smells—that’s how it tastes,” Sitter says. “It’s actually very pleasant.”
Similarly, at London’s Silk & Grain, which matures cocktails using various materials, including wood, metal and glass, animal hide fits right in. Dalwhinnie 15-year-old single malt scotch infused with vegetable-tanned leather appears in several drinks, including the Leather Penicillin (garnished with a leather shoelace), the Queen of Cornhill (leathered whiskey, tequila, absinthe and mint, topped with sparkling wine), and the Bloody Moira, a Bloody Mary variation with beef broth and beet root.
Although we’re not quite ready to start slicing up our favorite leather jacket to steep in tomorrow night’s cocktail, bartenders insist that leather-aging is more than just a gimmick—it’s a technique to add to the toolkit. Rojo points to the evolution of the Under My Skin cocktail when it meets ice: the once-dominant leather aroma slowly cedes to the spice and citrus notes of the spirits, while the leather adds structure that stands up to the slowly dissolving ice. “What begins aggressively ends elegantly,” he says.