Whisky producers are on a ceaseless path of innovation. To make new entails some redefinition of the old. The idea that distillers are the custodians of tradition is a dated one, as the industry moves towards fresh methods to revitalise a storied past. Over the past two years, the use of unusual cask finishes has gained momentum as means to add a novel dimension to the flavours of whisky.

Cask finishing, also known as secondary maturation, is not entirely new. A whisky, after primary ageing, is transferred into a different barrel for a shorter time period in order to enhance its profile. It’s an avenue for experimentation, where distillers can toy with the influence that different wood varietals have over their whiskies. Ex-cognac barrels, port pipes and sherry butts have long been some of the most widely used options, but now, producers are going beyond and clamouring for radical (some say bizarre) choices that range from ex-amaretto to tokaji casks to finish their masterpieces.

From independent distillers…

A trend ripens when big names adopt it, but its origins tend to stem from humbler grounds. Isle of Arran, a 22-year-old independent distillery from the Island region of Scotland, was one of the very few to chart its way into the virgin waters of unusual cask finishes in 2005.

unusual cask finishes whisky
Arran distillery.

Jaclyn McKie, a representative from the distillery, was at a whisky tasting when she pinned the start of something new. A writer, in its tasting notes, had likened one of Arran’s younger expressions to calvados, an apple brandy from Normandy. The idea to finish an Arran whisky in an ex-calvados barrel struck the distillery’s production director, and so, it moved into purchasing casks from Christian Drouin, a famed calvados producer.

“It started out as a small experiment. We put our aged single malt whiskies into calvados casks for about six months, and the results were released as a small, single pass bottling. It was very well received,” said McKie.

unusual cask finishes whisky
Arran has evolved leagues despite being a relatively young player in the Scotch industry.

Since the sold-out reception, Arran has plowed its way through an army of alternative wood types, going from barrels that used to store amarone, sauternes, and even champagne. Each experiment has gained such popularity that Arran has made two unusual cask finished whiskies part of its permanent repertoire — the Arran Malt Amarone Finish, and the Amarone Malt Sauternes Finish.

…to the mainstream

A little over a decade after Arran and other small-batch distillers made forays into the field, giants like Glenfiddich and Johnnie Walker have come forth with their own permutations of such unexpected finishes.

In 2017, Glenfiddich unveiled its Experimental Series, which comprised the IPA Cask, where its whisky was finished in barrels that aged craft Indian Pale Ale, and the Winter Storm, where French oak casks that used to house Peller Estates’ ice wine saw new life as vessels for secondary maturation.

unusual cask finishes whisky
The IPA Cask manages to retain the light, fresh fruit notes of a classic Glenfiddich, with an added hoppy, bitter edge at the finish.

Within the same year, Johnnie Walker unveiled a new suite of whiskies, titled Blender’s Batch. Out of the three whiskies created, two involved alternative casks — the Johnnie Walker Wine Cask Blend and the Rum Cask Finish. Aimee Gibson, a member of the distillery’s blending team, explains that the former is a blend of “whiskies drawn from the four corners of Scotland”, of which some are matured in wine casks, and the latter finishes a mix of whiskies in casks that held Caribbean rum distilled in pot stills.

unusual cask finishes whisky
Two of the three whiskies in the 2017 Johnnie Walker Blender’s Batch suite.

As with any trend cycle, an assumption is that the entrance of major industry players signals its becoming mainstream, but Matthew Fergusson-Stewart, the Asia Pacific Regional Brand Ambassador for Glenfiddich, stresses the contrary.

“To be honest, this level of experimentation has always gone on at one level or another. It’s just that distillers are better at talking about it these days.”

Moulding tradition

The adoption of unusual cask finishes comes at a time of a declining market share for Scotch, so its not surprising that this move has made each brand more appealing to a wider market share, allowing some to dive into uncharted waters.

unusual cask finishes whisky
Glenfiddich Malt Master Brian Kinsman and Seb Jones of Speyside Craft Brewery.

For Glenfiddich, it was the craft IPA market. The distillery had to develop its own beer to mature in casks, which led to a collaboration with Seb Jones of the Speyside Craft Brewery. Fergusson-Stewart told us that this union, and the promise of the world’s first IPA cask finished whisky, helped Glenfiddich tap on a new market rife with craft beer devotees.

Consumers have also evolved into a discerning and experimental bunch, willing to venture into new flavours and unfamiliar profiles. This nudges distillers to stretch their idea of the spirit beyond its customs. “It all comes down to uncovering flavours that are going to delight consumers,” said Gibson.

This sentiment was echoed by McKie: “They’re looking for something more than the regular options they’ve been seeing forever on shop shelves.”

Unusual cask finishes achieve just that, while remaining within the strict legal guidelines that define Scotch whiskies. Each representative we spoke to emphasised that this trend did not mean distillers are dumping their craft heritage for more options, but are growing dynamically with present demands.

Beatrice Bowers
Features Editor
Beatrice Bowers writes about beauty, drinks, and other nice things. When not bound to her keyboard, she moonlights as a Niffler for novels and can be found en route to bankruptcy at your nearest bookstore. Don't tell her boss.