Demystifying Mizunara Virgin Oak

Mizunara is an oak variety that has been increasingly grabbing the attention of whisky enthusiasts. Traditionally, distillers have used American oak (Quercus Alba) and European oak (Quercus Robur) to shape the character of their spirits. However, the rare Japanese oak is becoming increasingly sought after by whisky makers.

Mizunara oak (Quercus Crispula) roughly translates to ‘water oak’ in Japanese, referring to its high water content. Compared to other oak varieties, it has to dry for a much longer period once felled. It grows in the cold climates of northern Japan, making it less abundant and notoriously difficult to work with.

Unlike American and European oak, Mizunara trees take much longer to mature – around 200 years – which makes them much less readily available, increasing their value. They also grow crooked with lots of knots which means each tree yields less timber. The wood is very porous, which means the spirit is able to interact with the wood more and take on rich flavours from the cask. However, this does create challenges, as the casks are also more likely to leak.

Despite the challenges, the increased interaction between the spirit and the cask creates an extremely rich and flavourful spirit. Unlike American oak which produces typical notes of caramel and vanilla or dried fruit and spice from European oak, Mizunara imparts flavours often associated with Japanese incense—sandalwood, coconut, and oriental spices like clove and cinnamon. There’s also a subtle floral quality, with hints of exotic fruits such as yuzu and lychee.

The GlenAllachie is known for its innovative approach to cask selection, and Mizunara oak has played an exciting role in some of The GlenAllachie’s new releases. Under the leadership of Master Distiller Billy Walker, The GlenAllachie has experimented with a wide range of cask types, from Fino and Amontillado Sherry casks to Chinquapin and Scottish virgin oak. By using Mizunara casks for secondary maturation, The GlenAllachie has been able to balance the wood’s exotic character with the distillery’s signature rich, honeyed malt style.

Commenting on the use of Mizunara, Billy said: “As a chemist, I find both cask management and blending truly fascinating. I feel incredibly fortunate to have worked with Mizunara, a very uncommon Japanese oak that provides exceptional character but, in turn, throws plenty of challenges our way. Having said that, the result is beyond worth the trials and tribulations.”

The GlenAllachie recently launched the first single malt to join the Masters of Wood series: a 17-year-old Mizunara & Oloroso Sherry Cask Finish, featuring whisky matured in rare Mizunara oak barrels combined with spirit from rich Oloroso Sherry puncheons and hogsheads.

“The flavour delivery from the Mizunara barrels, interwoven with the nutty, spicy character of the Oloroso casks, culminates in a spectacular single malt with delectable notes of apple strudel, runny honey, chocolate-covered hazelnuts and stem ginger. This is indulgence at its finest.”

While Mizunara oak barrels may be rare, expensive, and difficult to work with, the results are undeniably worth it. The addition of Mizunara oak adds depth, complexity, and a touch of elegance to whisky, rightfully establishing it as an expression worthy of the Masters of Wood series.

Watch Master Distiller Billy Walker talk through and taste the 17-year-old Mizunara & Oloroso Sherry Cask Finish here and buy your bottle here. 

TASTING NOTES

The GlenAllachie 17-year-old Mizunara & Oloroso Sherry Cask Finish – 50% ABV

• Colour: Intense Mahogany.
• Nose: Heather honey, dried orange peel and crystalised ginger, with notes of cocoa, toasted tobacco leaves and fresh vanilla pods.
• Taste: Baking spices, dried blood orange and grilled honeycomb, followed by bursts of rich cocoa, poached cinnamon apples and fig syrup, with pecans and demerara sugar.