Dewar’s has been making waves in the blended scotch space with its cask finished series in recent years, releasing a rum cask finished expression in 2019 and following on since then with finishes in mezcal and port barrels. This month marks the unveiling of the latest edition in this series, Dewar’s Japanese Smooth, finished in mizunara oak casks.
Mizunara oak, known for imparting floral, sandalwood, and gentle spice notes to whisky, is native to the mountain forests of Hokkaido, Japan’s northernmost island. It is a rare wood type, owing to the remarkable fact that mizunara trees require multiple centuries—in the realm of 200 to 500 years—to reach full maturity. Mizunara first became useful to Japanese whisky makers in the mid-20th century, when European and American oak became unobtainable during World War II. It remained solely in the toolkit of Japan’s distillers for many decades thereafter, becoming most closely associated with Suntory’s Hibiki blend and Yamazaki single malts. The discovery of mizunara by non-Japanese distillers is only a recent phenomenon, and its use in scotch whisky has been primarily with single malts—led by Bowmore Mizunara Cask Finish. Until the arrival of Dewar’s Japanese Smooth, the lone mizunara expression in blended scotch was Chivas Regal’s Mizunara Cask Finished, released in 2019.
Working with mizunara thus was a new experience for Dewar’s master blender Stephanie Macleod. Her first mizunara casks arrived in early 2020, medium toasted by specification, fully intact, and carefully wrapped. Macleod had them filled with water for 24 hours to re-swell the wood and ensure the staves were properly joined—mizunara being a notoriously brittle wood type. Once the casks were filled with Dewar’s 8 year old, she noticed how rapidly the liquid began to transform.
“After about a month, we started seeing a change in both color and flavor profile,” says Macleod. “I wasn’t expecting anything to happen so quickly, but I was relieved that we were seeing a difference. We didn’t just want to say ‘this whisky has been in a mizunara cask’—we wanted to show the benefits of this finishing, and not just call out the name mizunara.”
The whisky was kept in mizunara barrels for three months. “With any type of finishing, we want to make sure the wood doesn’t dominate the whisky’s flavor,” notes Macleod. “After three months, I felt that we were getting a good balance of the Dewar’s character and the aspects of the mizunara oak.”
Discovering New Flavors
Notably, mizunara is among the few types of new wood available to scotch producers—the other prominent option being virgin American oak. New wood tannins can be aggressive, creating the risk of over-oaking. “But we didn’t see that [tendency] with mizunara,” says Macleod. “It was very gentle, and very subtle. Along with the Dewar’s heather and honey notes came the [mizunara’s] intense floral notes of sandalwood, spice, and syrupy-citrus notes of lychee.”
Dewar’s has also filled some of its mizunara casks for further aging, to see what else might emerge in the future. “We’re tasting them regularly to see how the whisky does when it’s been [finished] in the barrel for a year or two,” says Macleod. “We’re constantly reviewing it.”
But Macleod is proud of the fact that Dewar’s has used a relatively young whisky—its 8 year old—for the cask-finished series. “A whisky doesn’t have to be 12 years old or more to be interesting,” she says. “We’re making a statement that younger whiskies, provided they’re in good casks, can give you all the excitement and complexity of the older expressions.”
Whisky Advocate scored Dewar’s Japanese Smooth at 91 points in its Summer issue.