It all started with Glenmorangie. They may not have been the first distillery to have tried this, but with the launch of their wood finish series in the 1990s the concept of multiple cask maturation of whisky was established in the industry. Competitors were reluctant first, but when it became clear that the new range was more than a short fad, others followed the example.
Notably Edradour and Bruichladdich along with their affiliated independent bottler Murray McDavid were among the first who embraced cask finishing, at times creating the impression that no wine or spirit cask was safe from their experiments which prompted reactions ranging from enthusiam to disgust.
More and more distilleries began to offer cask finishings or multiple maturations. The Balvenie Doublewood has even become the standard entry level bottling of that distillery, and Diageo’s Distillers Editions are strongholds in their product portfolio as well. Today we are hard pressed to name a distillery that has not done such bottlings yet.
While the use of multiple casks for maturation was originally intented to infuse the whisky with flavours of other drinks, the experiments have not stopped here. Focus is more and more on the wood itself rather than on the previous liquid contained in the cask. This industry trend has become so prominent that one could wonder if the spirit itself has become secondary.
The days where “any cask that was not leaking was a good cask”, as one distllery manager put it, are gone for good. Today, distilleries create jobs called “Master of Wood”, Glenmorangie grows the wood for their casks in the Ozark Mountains where oaks supposedly grow particularly slow. And Macallan and Dalmore proudly report about their custom-seasoned sherry casks made for them in Jerez.
Oh yes, since transport sherry casks are no longer available, sherry casks used in the Scotch whisky industry are usually custom-made. The romantic notion of genuinity and cask recycling has nothing to do with the reality where sherry casks are tailored to order in Spain. And the sherry used for “seasoning” the casks may be used for sherry vinegar afterwards. Of course in a way this is a legal cheat, but it gives the distillers greater control of the result. If it were not for that dreaded sulphur… But that is a different story.
The use of fresh or “virgin” oak casks for Scotch whisky – unthinkable of a few decades ago – is something completely normal nowadays. Such casks are used for finishing purposes or even for complete maturation like in the Bunnahabhain Darach Ur. Also smaller cask sizes have been used lately, like the 125 litre quarter casks or even the tiny 40 litre blood tubs. Extreme “Alligator” cask charring has been tried as well.
Looking at currently available bottlings of Sotch whisky, there is a remarakble number that feature “wood” in some way. Laphroaig Quarter Cask, Triple wood, PX Cask; Balvenie Doublewood, Auchentoshan Three Wood, Springwood, Heartwood; Bunnahabhain Darach Ur; Ardbeg Alligator; Glenmorangie Ealanta. The list goes on.
Why has wood become so important today?
Something is very strange here. Many experienced whisky lovers think very highly of bottlings from the past. Old Ardbegs, Bowmores, Macallans, Taliskers and even old standard blends bottled in the 1960s and 1970s are highly sought after, not only because of their rarity, but not the least because of their quality. And this was the time when wood mattered much less than today. In addition to that many of these whiskies were bottled younger than today. The Aberlour 8 yo in the square bottle is one of those classics, or the Macallan 7 year old. It seems that whisky matured quicker back then.
At least part of the answer lies in the barley. The higher the impact of the wood, the lower the relative impact of the spirit. Or to put it the other way around: It the spirit is weaker, you need more wood impact to get a decent whisky.
Today’s barley varieties have a much higher alcohol yield than the ones used decades ago. The alcohol yield is equvialent of the amount of raw starch convertible to sugar in the grain. But if you have more starch, you must have less of the other things that make up a grain of barley: mainly proteins, minerals and fats. The starch gives us the ethanol in the spirit. Its flavour is determined by those other components. Even though the chemistry behind fermentation and distillation is extremely complex it boils down to a simple equation: More alcohol, less flavour.
Six year old whisky in the 1960s was good enough to give standard blends a remarkable quality. Today’s standard blends have the same age but taste rougher and much less mature.
Most modern single malt whisky is now aged 10 years or longer. Or perhaps we should say “used to be”. Because the pendulum ist beginning to swing back again towards shorter maturation times. The number of no age statement bottlings has been steadily increasing in recent years, and many of those feature “modern wood” as explained above.
The astonishing creativity of whisky makers in using different casks for maturation is without a doubt connected to the desire to bottle whisky at a younger age (trying to ‘save’ weak casks with strong finishes is another incentive). But of course wood extraction is not the same as maturation. Some processes inside the cask have nothing to do with wood, and they take time even when you try to speed up things by the clever use of wood. This does not necessarily mean that such wood-driven whiskies are worse than spirit-driven ones. Some of them are actually wonderful. But if this trend goes on, it will be harder and harder to find good spirit-driven whiskies.