In the art of barrel-making, toasting is a fairly straightforward process. Prior to charring, coopers use heat to slowly break down compounds in the wood and release sought-after flavors, just like toasting a marshmallow over a campfire. Typically, coopers accomplish that by using gas ovens, electrical tubes, or woodfires. But a new Dewar’s expression was finished in a cask toasted with an unlikely tool: magma stones.
The process starts with new Limousin French oak barrels, which are loaded onto a contraption resembling a hollow cylindrical chamber, which sits horizontally above a square base with four wheels attached. The barrel lies on its side, placed over the chamber—which hovers just above the barrel’s surface without touching it—with its hoops resting on the wheels. Icelandic magma rocks are then heated up and shoveled into the chamber, toasting the barrel using indirect heat; as this happens, the wheels start to spin, turning the barrel around the chamber and ensuring that the toast is applied evenly. The process takes about an hour, a bit longer than the industry range of 9 to 40 minutes. It’s broken down into two 30-minute phases: The first half uses stones that are heated to 390°, and the second half uses much hotter stones that are heated to 480°.
Dewar’s 21 year old Magma Stone Toasted was finished in those curious casks for 6 months, and was bottled at 46% ABV. It’s currently available nationwide in limited quantities, with a suggested retail price of $140.
Using exotic rocks to toast a cask may seem like an alien concept, but it’s a practice that comes from the wine world. The idea is often credited to Thomas Moussié, founder of the Bordeaux-based Maison Moussié cooperage, who’s been doing it for over two decades. In the early 2000s, Moussié was trying to find a way to make barrels that would create wines that are fruitier and fresher without overdoing oaky or tannic notes. After taking inspiration from saunas, which produce steam via water and heated rocks, he started to experiment with toasting wine casks using stones that conducted heat well. By 2018, he gained a patent on a lava stone-toasting process, and shortly after that he patented a similar technique which used jade. In 2023 the cooperage was acquired by Independent Stave Company, and today it still offers stone-toasted casks through its Petra Collection product line.
Silkier Textures, Richer Flavors
The whole thing sounds gimmicky, but Dewar’s master blender Stephanie Macleod—who first heard about it through its use in the wine industry—believes that it makes a serious difference in whisky compared to a traditional direct-fire toast. “Stone toasting is a much more delicate and controlled process that eliminates the charred, ashy notes that can sometimes accompany traditional methods of toasting,” Macleod told Whisky Advocate. “[the stones] very slowly toast the wood and season the oak—allowing us to extract silkier textures and richer flavors from the cask.” She identifies those key flavors as cinnamon, clove, caramel, baked apple, and toasted cereal, adding that stone-toasting can also contribute refined fruit notes that aren’t readily brought out by casks toasted using fire or gas.
The release is part of Dewar’s Double Double series, which launched six years ago and has been something of a game changer for the franchise. Dewar’s has long had a major presence in the market— it was the No. 1 scotch in the U.S. until 2005, and currently it holds the No. 2 spot behind Johnnie Walker. It had largely built that success on White Label, its budget-friendly, non-age stated blend that’s a go-to for many on a regular basis. But amid the modern whisky renaissance, aficionados were overlooking Dewar’s in favor of age-stated single malts.
Despite releasing various high-quality expressions over the years, Dewar’s was never really able to shake the perception of being a beginner-friendly scotch brand for Highballs rather than one to be sipped and savored neat. But the dial moved when the first Double Double releases hit the market. The name derives from the Dewar’s tradition of aging and blending twice, the second aging being a finishing. In a four-step maturation process, master blender Stephanie Macleod separately blends parcels of aged malt and grain whisky, leaves each to marry for some time, then blends them together to marry again, before finishing the liquid in a specific cask. The line debuted in April 2019 with three expressions: 21 year old Oloroso Cask, 27 year old Palo Cortado Cask, and 32 year old PX Cask. All three were bottled in a 375 ml size, and carried prices ranging from $50–$150.
The trio was impressive, with the 32 and 21 year old each garnering a 94-point rating from our tasting panel. The 21 year old was named our No. 2 Whisky of 2019 later that year. It was a watershed moment for Dewar’s, proving it could truly work at the premium level, attracting attention from even the most discerning drinkers while holding its own against many single malt scotches in the same price range. Those expressions would go on to inspire other intriguing innovations at Dewar’s, including the similarly focused Smooth range later in 2019—which showcased cool finishes at a more affordable price point—as well as a reformulated Dewar’s 12 year old in 2022. Dewar’s would also extend the DD series with new blends over the years, including some ultra-premium blended malts and a 21 year old finished in mizunara barrels.
No Stone Unturned
Regarding this latest edition, Macleod also plans to use stone toasting for other Dewar’s projects in the future, though the process won’t be exactly the same. For example, she’s already put together another blend that was finished in casks toasted with heated jade—a breathtaking green-hued rock that’s renowned for its use in Chinese artwork and statues—that will be available in certain markets. “We’ve found that utilizing different stones, adjusting toasting durations, and employing various oak types can yield diverse flavor combinations in the final liquid,” explains Macleod.
