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Bigger Than Whiskey: How Mizunara Oak Barrels Became a Brand

Via Vinepair

On the surface of things, mizunara oak seems like the worst material for making casks that will one day age spirits. The indigenous Japanese species takes at least 200 years to reach maturity before it can be chopped down and made into casks. The wood’s structure is inherently porous and lacks waterproofing oil enzymes, so staves must be cut along the grain to minimize leakage. Along with the species’ stubborn reluctance to grow straight and its high concentration of knots, the process brings wastage and increased cost. Even when cut along the grain, it can take coopers two or three builds, with additional staves added each time, before they’re sure the barrel is watertight. And even then, mizunara casks leak a volume of spirit each year on top of the expected angel’s share. As Jeffrey Karlovitch, master blender of Kaiyo Whisky, puts it, “We lose 3 percent to heaven, and 4 percent to hell.”

All things considered, it’s unsurprising that mizunara oak was ignored by distillers and almost exclusively tapped by Japan’s luxury furniture industry until the mid-20th century. But fast-forward two decades into the 21st century, and things have changed dramatically. Mizunara oak casks hold a place among the most coveted aging vessels in the spirits industry. More than a material for making barrels, mizunara has become a brand: Where distillers have the fortune of resting their spirit in the casks, the mizunara name is emblazoned on bottle labels, often rivaling the producers’ for size and prominence. “It’s almost bigger than brands,” Karlovitch says. “It’s that special.”

The history of using mizunara for spirits casks is one of ingenuity birthed from necessity. The commonly recounted version suggests that after World War II, import restrictions meant Japanese distillers faced a shortage of casks to age their whisky. At the same time, whisky was proving so popular with the occupational armed forces that producers had to find a domestic alternative. And so they turned to their native oak, mizunara.

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