Cask Finished Whisky

CASK FINISHED WHISKY: The Final Frontier WORDS ° Ben Davidson

Whisky in all its guises continues to be the favourite spirit amongst bartenders and board directors alike. It’s appeal with the trend-setting bartenders of the world’s finest bars and their ability to communicate about the differences to their customers has continued to recruit new devoted fans to the category every year. There are now armies of ambassadors, whisky zealots and ‘malt advocates’ who passionately share their knowledge about their new favourite whisky to consumers and friends. (I should know, because I’m one of them). At the same time, at the top-end of the market, luxury whiskies continue to grow, as the prestige associated with rare and expensive whisky becomes more apparent with a deeper understanding and appreciation of the care that goes into making a 50 year old Scotch whisky and why they can command prices of over $50,000 a bottle.

The unabated growth in whisky as a category has lead to shortages of aged stocks and over the last few years there have been a plethora of new whisky blends containing younger whiskies to replace their rarer ‘guaranteed aged’ older siblings. This increased demand has led to the need to innovate within the category to create new ‘expressions’ that contain younger whiskies that enhance the master brand while attracting new consumers to the category.

“Whisky has a story that is both romantic and practical, emotional yet rational; it’s part artistry, part science and once initially hooked, it becomes intriguing, then quietly captivating and eventually can border on obsession, as it’s the classic scenario of the more you know, the more you want to find out.”

Being that whiskies are made from a simple mash of cereal grains, yeast and water there is a surprising number of distinctly different flavour profiles across the broad category. The key variables being – the different percentages of the grains used in the mash, the type and shape of still and the qualities of the water used for dilution, that gives rise to initial varying flavours. However, it’s in the final step in the process - ageing and maturation, where the whisky develops most of its distinct character and flavour.

Perhaps it was the cost savings of used American oak barrels that were the main reason for adopting them for ageing whisky in the late 19th century. So much so, that the term ‘traditional casks’ is used to describe the now common practice of using ex-bourbon barrels for the ageing of most whiskies. It was subsequently discovered that the softer, more gentle uptake of the woody characters was better and it promoted subtle vanilla and sweet coconut notes in the whisky due to the caramelisation of the lignin and wood sugars. Similarly, the shipping of Sherry from Spain to the UK was usually done in large 500 litre European oak ‘butts’ up until the 1980s, which were re-used at the point of destination as a great vessel for ageing whisky. The remnants of

the sherry in the casks proved to enhance and accentuate dried fruit and nutty characters in the whisky.

It has been said, in whisky circles, that distillation is a science and blending matured whiskies is an art and that as much as 80 per- cent of the final flavours in a whisky emerge and develop from and in the oak cask it rests in. Of course, it’s vitally important to get your newmake spirit right, because ageing can’t cover up a bad tasting spirit. The usage of different types of cask made from different species of oak and the flavours they promote has been understood for a while, and there are ‘house’ styles that have emerged favouring one type of cask over another. Aberlour A’bunadh is aged exclusively in ex-oloroso sherry casks for its maturation, giving it dried fruit, dark cacao, oak varnish-like aromas, whereas, others in Speyside like The Glenlivet 12 year old have gone for exclusive ex-bourbon casks, with the whisky bursting with pineapple, vanilla and tropical fruits aromas.

The majority of whiskies, however, don’t just use a single type of oak anymore. Most are vatted from a variety of different barrels and casks with a little sprinkling of whisky from butts, pipes and puncheons to add some spice! With most casks being ex-bourbon barrels there is approximately only 5 per cent of casks coming from an ex-sherry, European oak origin. Sherry butts are ten times the price of an exbourbon barrel.

‘Finishing’ a whisky, (apart from something you enjoy doing on a regular basis), is the term given to the creative process where the whisky is matured further in a cask of different origin, usually anywhere from a few months to a few years, to impart a new flavour to the whisky.

Usually, the first cask is an American oak, ex-bourbon barrel to give it a good base and the second cask is often European oak that may have been used to mature a different spirit like rum or Cognac, oloroso sherry or other fortified wines like port, Madeira, or wines such as pinot noir or ex- Bordeaux red casks and even beer casks like stout and IPA and even a ginger beer cask finish!

Some of the earliest and well-known ‘special finish’ whiskies include the Balvenie ‘Doublewood’, and the Glenmorangie fortified wine finished range.

So, in the spirit of innovation and creating n ew products for the new legions of whisky lovers the producers have been quietly developing an array of ‘finished’ whiskies to add a new dimension to their range and to give their fans a new expression to get excited about.

UNDERSTANDING OAK MATURATION

The use of oak casks as the preferred vessel to mature whisky in didn’t happen overnight. It was a realisation through trial and error that whisky was improved by resting in oak barrels. As luck would have it, the most abundant varieties of oak trees from North America and Europe have the key elements needed to keep a whisky for a long time; strength, density, porosity and unique chemistry that gives rise to complex and delicious flavours over time. Because the oak is defined as a ‘pure wood’, it is ideal for the purpose, as long as it’s rested and ‘weathered’ for a couple of years to allow for the bitter compounds to oxidise and transform, before the casks are made and whisky added. The key variables here are the growth rate of a tree, the natural seasoning of the wood and the level of toasting or charring during the coopering process.

Once in the cask there is a lot of interactivity between the oak and the spirit. Complex processes take place over extended periods of time which aren’t fully understood, however the role of oxygen and temperature are important variables.

There are four processes that take place over the long maturation process:

• EXTRACTION: the process where the spirit is dissolving and absorbing the sweet wood sugars, tannin, lignin, oak lactones and colour from the oak staves in the cask. Increases as temperature increases.

• SUBTRACTION: where the cask can help remove unwanted flavours in the spirit like sulphur and organic nitrogen compounds.

Also, helps eliminate ‘immature’ flavours from the spirit.

• INTERACTION: where there is a complex interplay between the spirit, oak and air that aids in the conversion of organic compounds like tannins into acetals, lignins breaking down into soluble lipids and acids being transformed into fruity esters.

• OXIDATION: is the key factor that promotes the most complex flavours. The slow breathing of atmospheric oxygen through the cask staves is made more active by the presence of tannins. The result is the creation of fragrant, almost ethereal aromas that lie at the heart of any good whisky. In a cooler climate, there is more influence of oxidation and hence fruity aromas and slower oak absorption, whereas in a warmer climate the balance is tipped toward faster oak absorption and not as much time for oxidation to fully develop.

MAIN TYPES OF OAK USED FOR MATURATION

NORTH AMERICAN • White Oak – Quercus alba

Commonly known as White Oak, it’s the species used in the maturation of most American whiskies. It’s a very strong wood with coarse grain structure and a density of .75gm/cubic cm. Said to have a higher percentage of tannins, especially vanillin, and is also higher in lignin and lactones compared to other oak. Results in a more vigorous uptake of oak flavours.

EUROPEAN • ‘English’ Oak - Quercus robur

Also known as common oak and has been a prized wood for boat building and construction over the centuries. Very strong and durable oak with a coarse and irregular grain structure. Has been used extensively for sherry maturation, after which it is sometimes called ‘Spanish Oak’. Has a density of .69gm/cubic cm.

• ‘French’ Oak - Quercus petraea

Also known as Sessile oak and commonly comes from the planted forests of France. It’s known for its tighter and finer grain structure and softer tannins compared to White Oak, which gives a more gradual and softer uptake of oak flavour development. Has a density of .71gm/cubic cm.

JAPAN • Japanese Oak – Quercus mongolica

Also known as Mizunara Oak, it tends to have a slower growth rate which results in the wood being slightly lighter and weaker than White Oak. It has a high vanillin content giving good flavour to the whisky. Japanese Oak is used as a finishing cask due to its porosity. Density .68gm/cubic cm.

WHISK(E)Y TASTING CASK FINISHES

The finishing cask does impart flavour to a whisky, and there are a wide array of distilleries now producing a range of expressions that have been finished in different barrels; from multiple wood casks, to sherry, rum and even beer to add another layer of flavour and complexity to the whisky.

We thought it was fitting to bring together an eclectic group of Whisky professionals to taste how some of these ‘cask finishes’ have developed flavour and added complexity to the whiskies. For the tasting, we selected a variety of whiskies from around the world including Ireland, Scotland, the USA and Australia, all with variously different cask finishes. We wanted to see if our panel could comment on the flavour profile present and the influence of the special cask finish.

We were lucky enough to be hosted by one of Sydney’s newest and finest venues, Mjolner, a Viking themed whisky bar in the inner-city suburb of Redfern. As a treat, we were graced by not one but two Keepers of the Quaich on the panel in Ben Davidson and Sven Almenning.

THE PANEL

BEN DAVIDSON Drinks Curator, Drinks World magazine

SVEN ALMENNING Director, Speakeasy Group

JAMES BUNTIN The Whisky Ambassador

ROSS BLAINEY

Brand Ambassador, The Balvenie

ALEXANDRA DAHLENBURG

Venue Manager, Mjølner

ANDREW RATCLIFF Senior Bartender, The Baxter Inn

MATT WOOLER Founder & Curator, Dramnation

DAN WOOLLEY National Whisk(e)y Ambassador, The Exchange

LUKAS RASCHILLA Editor, Drinks World magazine

THE WHISKIES

WOODFORD RESERVE MASTER’S COLLECTION BRANDY CASK FINISH

45.2% ABV

The American oak brandy barrels that have been selected were first used to mature whiskey and then many more times for ageing brandy. Finishing fully matured Woodford Reserve in these barrels accentuates the rich dried fruit and nut character from the grain recipe and the long fermentation.

PANEL:

Sven Almenning: Very influenced on the nose by the brandy, grappaesque with some peppery after notes. Very rich and creamy on the palate. Ben Davidson: The classic Woodford sweetness is dried out a bit by the brandy cask adding a toastiness. Nice subtle brandy richness from the cask. James Buntin: There’s a massive raisin note. Similar to rum n’ raisin ‘Old Jamaica’ chocolate, it’s not far off that. It’s also quite nutty, like a pistachio. Tastes heavily brandied to me.

Andrew Ratcliff:

You can smell classic Woodford under the heavy aroma of toffee and white chocolate.

JAMESON CASKMATES STOUT CASK FINISH

40% ABV

Emerging from a conversation between Jameson head distiller and the head brewer of Cork’s Franciscan Well Brewery, Jameson Caskmates has been finished in stoutseasoned whiskey casks. While the triple-distilled smoothness is very much intact, notes of cocoa, coffee and butterscotch confirm the stout influence.

PANEL:

Dan Woolley: Sweet honey and light flavours. Pleasant, light entry with a growing intensity toward the finish. Ben Davidson: Slight malty, bitter chocolate note on the nose, but with the classic Irish whiskey, rich fruitiness. Definitely noting additional flavours and complexity compared with standard Jameson. Lukas Raschilla: Notes of honey, sweet toffee.

GLENFIDDICH EXPERIMENTAL SERIES IPA CASK

43% ABV

This is the only single malt Scotch whisky to be finished in India Pale Ale (IPA) craft beer casks, done in collaboration with a local Speyside craft brewer who designed a beer that would go into whisky casks.

PANEL:

James Buntin: I find it to be a little more spicier on the nose. Taste of apple crumble, or apple strudel. Sven Almenning: This whisky has notes of stewed apples and is quite floral. Flavours are slightly spicier than the regular Glenfiddich, traces of cacao and roasted nuts.

Alexandra Dahlenburg Ben Davidson

Andrew Ratcliff: Classic Speyside on the palate with an added sweetness and a mild spice. There’s certainly an element of hoppy bitterness on the nose. Dan Woolley: A little bit of burnt toffee coming through. Much more intense, complex sweetness than the standard Glenfiddich 12. Stewed, spiced fruits coming through. A really well-constructed whisky. Alex Dahlenburg: The pepper comes through in the back of the palate with a mid length finish. A note of floral frangipani. Matt Wooler: Super dry in the back. Soft and round with manuka honey that develops into more of an apple pie.

HELLYERS ROAD SINGLE MALT PINOT NOIR FINISH

46.2% ABV

This pinot noir finished edition is Hellyers Road Original Single Malt Whisky aged in American Oak (ex-bourbon) and then finished in French Oak (ex-pinot noir) and provides unique complexities of a Tasmanian rainforest.

PANEL:

Ben Davidson: Very unusual, savoury nose to it. The pinot noir French oak cask adds a vinous, red berry, tomato and parmesan cheese aromas and flavours. Andrew Ratcliff: Cereal and malt. Breakfast! Matt Wooler: Aromas of bread and grapes. Flavours of big cereals, malted milk. Ross Blainey: Fresh pressed grapes plus yeasty aromas. Malt and cereal flavours. Interesting nose, like fresh grape juice. Lukas Raschilla: Fresh yeast, pizza dough like flavour comes through.

MICHTER’S TOASTED BARREL FINISH BOURBON

45.7% ABV

Made by taking Michter’s US*1 Kentucky Straight Bourbon and ageing it for an additional period in a second custom made barrel. The second barrel is assembled from 18-month air-dried wood and then slowly toasted but not charred.

PANEL:

Alex Dahlenburg: Toasted wood aromas. Flavours of strawberries and cream.

Chalky with a mid finish.

Ben Davidson: Definitely getting some sweet confectionary and toasty notes there. Toasted marshmallow, campfire oak.

Matt Wooler: Huge peppermint spice, high rye, toasty and dry.

Dan Woolley: It actually smells like toasted oak on the nose, straight up.

THE BALVENIE CARIBBEAN CASK FINISH

43%ABV

The Balvenie brand ambassador, Ross Blainey shared some insight into this expression. “This whisky spends 14 years in ex-bourbon American oak barrels, then finished for between three to six months in a barrel which previously had Caribbean rum in it. It’s a pretty short finishing time, but you get that rum character coming through in it. For me, the flavour in this, the honey that’s usually in The Balvenie changes to toffee in this. It’s got a bit of a darker, sugary note to it. There’s almost a hint of tropical fruit, like orange notes in there as well which adds another layer of complexity to it. For this,

David Stewart selected three rums for a blend from about 20 different rums that they were going to use to season the cask. The rum is put in ex-bourbon barrels and aged in Dufftown for six months.

PANEL:

Sven Almenning: Toffee, banana and porridge aromas. Tastes of sultanas, cocoa, banana and red apple, delicious! Ben Davidson: It’s like walking in Speyside listening to Bob Marley… Alex Dahlenburg: Sweet toffee and green apple.

Dan Woolley

Andrew Ratcliff: So much complexity in this whisky. Hello Speyside! Dan Woolley: Aromas of golden syrup and earthy notes. Marmalade, very light, baking spices and a long finish. I get some nice, lightly spiced marmalade coming through. Matt Wooler: Gentle and layered. Rich and spicy, then leather, white sugar and roasted apples. A journey in a glass. The short description I always use for this whisky is red toffee apples. It’s got white sugar, caramelised toffee, red apples. It’s got a little bit of coconut in the back, along with honey and leather characteristics The Balvenie is known for.

THE GLENLIVET NÀDURRA OLOROSO CASK

60.7% ABV

The Glenlivet Nàdurra range features distinctively different cask maturations.

This expression has been matured exclusively in ‘first fill’ Oloroso sherry casks and is bottled at Cask Strength.

PANEL:

Sven Almenning: Rich, Christmas cake aroma. Wow. Tastes rich and creamy, like sultanas and dark, bitter chocolate. Dan Woolley: Stewed prunes note. Flavours of quince paste, cocoa and coffee grounds. Alex Dahlenburg: The aroma is heavy in apricots and macadamia. Matt Wooler: Dark fruits, rich grapes, and nuts on the nose. Ben Davidson: Bold aromas of date and dried fruit, toasted marzipan nose tinged with varnish. Huge and powerful concentration of tastes in this delightful sherry-bomb.

THE GLENMORANGIE BACALTA

46%ABV

The eighth release in the Private Edition from Glenmorangie. The Bacalta is a single malt first matured in ex-bourbon casks, then extra matured in bespoke casks baked under the sun which once contained Malmsey Madiera – the sweetest and most prized of the Madiera wines.

PANEL:

James Buntin: Just excellent, soft fruit, honey and butter. That’s honey as! I get a lot of honey in there, creamy caramel as well. Ross Blainey: Light on the nose, sweet white bread lightly toasted and honey. Reminds me a little of Werther’s Originals. Andrew Ratcliff: Madeira all up in my nose! Exactly what it says it is. Alex Dahlenburg: Fresh honeycomb, as if you’ve just take a knife to the beehive. Dan Woolley: Brandy snap biscuits, spice and honey. Cake, oak and polish. Amazing profile. It’s like Madeira cakes. Ben Davidson: Candied orange, honey and apricot nose, with baked fruits and toasted almond. That Madeira finish has layered on some delicious concentrated dried fruitiness.

LAPHROAIG TRIPLE WOOD

48% ABV

This expression of Laphroaig Islay Whisky has been matured in three types of cask. The first maturation is in American oak, ex-bourbon barrel. The most suitable of these barrels, containing a different range of different aged spirits are transferred into small, 19th Century style quarter casks for a second maturation. The final maturation is in large European oak oloroso sherry casks.

PANEL:

Ross Blainey: A beautiful balance of smoke, wax and rich cheese. Love! Hit of coffee and bitterness, balanced with a sweet jalapeno note and a long finish that turns to chocolate. Reminds me of Bavarian smoked cheese, with the wax on the outside and the smokiness to it. Ben Davidson: Has a lovely smoked salmon oiliness to the nose, then comes a burst of rich dried fruit and smoked salted almond and maritime influence. Matt Wooler: Fruit pies, salt breeze and wood fires. All my favourite things! Sven Almenning: Rich, smoky and complex. A favourite. James Buntin: Sweet peanuts, smoke and sea spray. Dan Woolley: Sweet, savoury, smoky, with aromas of cured meats and maritime mist. Followed by flavours of tobacco, leather and a salty savouriness with stewed prunes and molasses.