Finishing Touches: Five Great Irish Whiskeys, Five Powerful Finishes

May 29, 2022

Irish whiskey offers a sometimes bewildering array of whiskey flavours, descriptions and cask types. While they’re fun to explore, the sheer number of different maturation styles, woods used and the finishes applied can make a sometimes confusing (but delicious) flavour journey.

To try and unpick where a whiskey’s flavour comes from, we have to understand the difference between maturation and finishing. And then what each finish delivers to the bottled whiskey.

Whiskey generally has a first maturation of anything from three years upwards in oak (although usually much longer) which then can be finished in a different cask such as a rum, wine or cognac cask. While there are no set rules on how long a finish has to be, it is generally anything from three to 24 months. Anything longer than this starts to become a second maturation, and that’s a whole other story.

What flavours come from ex-bourbon barrels?

A large proportion of Irish whiskey receives its first maturation in ex-Bourbon barrels. These are made from American oak and this wood species creates a rich and mellow vanilla and caramel profile when maturing bourbon. The distillery cooper chars the inside of the barrel and this turns the sugars trapped in the wood into the chemicals which our nose and palate interprets as vanilla and caramel. The barrels generally arrive in Ireland wet with bourbon – that is, some of the bourbon remains absorbed in the wood. These characteristics are amplified when they are used in Irish whiskey maturation.

What is oak maturation doing?

When spirit is distilled, it has a number of flavours, one of which is a distinct metallic overtone. During maturation, the spirit interacts with the oak and this metallic taste is reduced. It takes around seven years for the wood to remove enough of it to be almost unnoticeable. It’s a thin, unpalatable flavour that you can quickly identify in young whiskey. Further maturation increases the complexity of the whiskey and the layers of flavour within it. Once the distiller decides the whiskey is mature they can choose to bottle it or finish it in another cask type to create a more distinct flavour. But which finish should they choose?

FIVE FINISHES

To look in more detail at what a cask finish can achieve, here are five Irish whiskeys, each matured in bourbon but with five different finishes. This is just a small example of the myriad finishes on the market but a good starting point.

THE WOOD FINISH

Glendalough 7-Year-Old Mizunara Cask
Matured in: ex-Bourbon
Finished in: Mizunara

Glendalough was the first distillery in Ireland to use Mizunara to finish whiskey. Mizunara is a Japanese oak wood that is incredibly rare and terribly expensive. Not only that, it is also extremely hard to work with, explaining why it was unheard of in Irish whiskey making before Glendalough introduced it.

But, as Glendalough discovered, it has an incredible impact on whiskey, creating layers of flavour that are delicate and yet intense enough that all the complications of using the wood fall away. The whiskey it produces is delicious, adding layers of coconut, incense and spices to the whiskey. This 7-year-old single malt, bottled at 46%, is an incredible example of what a Mizunara finish can achieve. On the nose you can expect citrus bursts, lots of vanilla and chocolate while on the palate it conjures more malty chocolate, cinnamon and rich tropical fruits. The finish is heavy with brown sugar and summer fruits.

THE RUM CASK FINISH

Grace O’Malley Rum cask
Matured in: ex-Bourbon
Finished in: Jamaican and Barbados Rum casks

Rum can deliver a punch of flavour that can obliterate some whiskey but, when done well, as the team at Grace O’Malley demonstrate, it can be the perfect edge to a superior whiskey. This blend of whiskey has double- and triple-distilled malt of up to ten years of age, which has been finished in wet casks of Jamaican and Barbados rum.
Both of these rum types are full-bodied and distilled from molasses in pot stills. Rum offers one of the richest flavour profiles in spirits distillation and layers complex tropical fruit aromas like bananas and mango. The flavours it delivers are equally rich and fruity with a distinct spicy element that comes from the wood.
Grace O’Malley’s rum-finished whiskey captures all of this but wrestles these exotic flavours into a whiskey that is distinctly its own. Stuffed with flavour and personality, it is a wonderful champion of rum-cask finishes.

THE WINE CASK FINISH

Fercullen Single Grain Amarone Finish
Matured in: Ex-Bourbon
Finished in: Amarone Wine Cask

Whiskey finished in an Amarone cask is a real treat. Amarone is a rich, red wine from Valpolicella in the north-east of Italy and is famous for its dominant flavours and powerful aromas. The wine is aged in barrels for up to five years, imparting all of its pungent personality on the wood. When this is then handed over to a whiskey maker, they need to use all their skill to harness the very best from the cask.
Fercullen’s single grain is a great example, and was the first of a limited series released under the Mill House name by the Powerscourt Distillery. Bottled at 46%, this superb single grain was finished for 18 months in the Amarone cask.
On the nose you’ll discover liquorice, vanilla, honey and citrus fruits. On the palate, the single grain offers a lovely smooth and silky experience that drops notes of cinnamon and chocolate into its layers. The finish is sweet and spicy, with a rich velvet texture.

THE COGNAC CASK FINISH

Lambay Whiskey Cognac Finish
Matured in: Ex-Bourbon
Finished in: Cognac

Lambay Whiskey, finished on the island of Lambay off the north Co Dublin coast, has put cognac finishes at the heart of their brand. Working in collaboration with Camus, the renowned cognac producer in France, they have bottled a series of single malts and blends finished in their cognac casks. Distilled in Co Cork, the company ships the whiskey to Lambay island where it fills the cognac casks and leaves them to finish for around six months.
Cognac has additional flavour compounds over its brandy sibling that deliver sweet, spicy and fruit-heavy notes with a touch of bitterness that connoisseurs adore. It’s often referenced with those dark descriptors such as leather and caramel and each of these make their presence felt in the Lambay casks.
The Lambay Malt version is bottled at 43% and includes double- and triple-distilled malt whiskey, while the oak used to age the cognac is French and this offers a more distinct oak edge than the American oak of the bourbon. The cognac and bourbon blend perfectly, with elegant rolling layers of flavour from both sides of the Atlantic.

THE BEER CASK FINISH

The Bridge Single Malt St Mel’s No1 Finish
Matured in: ex-Bourbon
Finished in: St Mel’s Brown Ale

Lough Ree Distillery is in Co Longford and this whiskey is their first experiment with beer cask finishes. It joins a happy bunch of bottles from lots of distilleries that have poured their whiskey into a wide range of beer casks, conjuring great new alliances with Ireland’s favourite drink (beer). Not surprisingly, Lough Ree chose a local brewery to partner with, putting St Mel’s brewery on their first beer-finished label.
Lough Ree sourced a red wine cask from Spain and sent it to St Mel’s Independent Brewing who swiftly filled it with a dark ale for 11 months. Once bottled, Lough Ree in turn refilled the cask with six-year-old single malt and let it finish for around three months. This created a wonderful balance of flavours that led to a soft and mellow single malt with lots of sweetness, fruit and honey. Citrus notes lead to a long finish with lots of spice and dark sugar.
Bottled at 43% , it is a single cask release that garnered lots of positive attention.