What is Mizunara Oak and why you should grab a Whisky Bottle when you see it

Marketing or not, it all started right at the end of the second world war, its story is deeply rooted in Japanese history and now mizunara has become a highly sourced wood.

A traditional Japanese oak that was never a choice for whisky distillers, turned out to be one of the most prestigious oaks in whisky maturing, adding the word “Mizunara” on whisky labels by whisky makers have increase the odds for those bottles not lasting very long.

Right at the end of World War II, the land of the rising sun was facing with shortages of any kind, from medicines, food and other commodities highly needed, therefore importing foreign cask for whisky ageing was not one of the country’s top priorities.

However, back in the days, whisky was the most popular drink within the occupational armed forces, therefore whisky distillers had to improvise and come out with a solution, and the wonders of mizunara were discovered, but it was not easy as you could have imagined.

Scarcer than European and American oak, and much more expensive, its story is deeply rooted in Japanese history. In recent days whisky makers around the world are trying to get hold of this prestigious wood barrels.

Mizunara’ s challenges

Mizunara oak trees do not grow straight, they tend to have a higher moisture content and are more porous

Mizunara oak trees do not grow straight, they tend to have a higher moisture content and are more porous than other wood varieties, says Hirotsugu Hayasaka – one of the oldest and most well-known coopers in Japan whom worked over 14 years at Nikka – so these issues make the casks vulnerable to leaks.

A Mizunara tree needs about 200 years growing before it can be cut and used for casks, and some larger distilleries have access to forests due to its location, however rights are often suspended by forestry local laws to help them to regrow, as it is considered an endemic oak tree specie of Japan, and given rise in popularity the Japanese government should work hard in protecting it.

The scarce available wood is then publicly auctioned with huge demand, prices have been soaring in recent years and a cask now cost over $6,000.

Whisky makers in Japan and across the world are having tough times laying their hands as larger producers normally get to pick first. So how such an unpromising and awkward oak ended up catching the eye of some of the world’s top distilleries.

The mizunara flavours and its difference

Mizunara oak imparts distinct sweet and spicy flavours with unique aromas reminiscent of sandalwood and incense and is also responsible for coconut and vanilla characteristics. Its complex range of flavours un-matched by other oak species. The early stages of maturation, the flavour imparted from mizunara oak is remarkably intense, making this the key determine fact to age whisky into these barrels for a minimum of 15 years, unless the maker opts cask finish.

What Hirotsugu Hayasaka used to a pain is instead a gain for whisky makers and whisky drinkers willing to pat the top price.

Mizunara market today

Most mizunara aged whiskies are sold in Japan with limited releases from their makers, making it this even more difficult for whisky drinkers around the world to get their hands in some of these bottles. Suntory is probably one of the main promoters of this type of this cask and even Chichibu goes even further with all of its distillery washback’s – see whisky glossary – are made of Japanese oak.

Suntory Yamazaki 18-Year-Old has been partially aged in Japanese oak, Yamazaki Mizunara series was extremely to find.

We have see some Cognac makers also use this type of wood and probably soon enough we will start seeing other range of spirits launching new premium cask finish label options.