Updated: Mar 4, 2021
WHY CASK MATTERS
A cask (Scotland) or a barrel (US) is a hollow cylindrical container with a bulging centre. They are traditionally made of wooden staves and bound by wood or metal hoops.
The cask maturation of whisky is one of the most influential processes in defining the taste of whisky. In Scotland, the spirit must mature in casks for a minimum of three years before it is legally allowed to be called whisky. While the length of time for cask maturation is important, the type of the cask however is crucial. The wood of the cask adds different complex flavours to the distillery character that is already in the new made spirit.
There are five major factors that affect flavours of whisky in a cask:
Reuse of the casks (first fill vs refill)
The influence by types of predecessor liquid is our major focus for this season.
TYPES OF PREDECESSOR LIQUID
During maturation of whisky, casks that have been used to store another alcohol are used to age whisky or finish whisky. Bourbon cask and sherry cask are the most commonly seen cask type in the market. There are also casks previously contained wine, port, rum, madeira, marsala, cognac for maturing whisky. Sometimes we would hear "Virgin oak" cask, which means fresh white oak casks that have not been filled any liquid before maturing whisky.
Bourbon cask refers to the casks that formerly aged bourbon whisky, which is an American whisky made primarily from corn. In the US, bourbon whisky is legally restricted to be aged in new oak casks only. Consequently a large supply of the used bourbon casks become available, which is just perfect to meet the high demand of casks for Scotch whisky.
According to Whisky.com, there are already more than 90% of all the world's whisky matured in bourbon cask.
Bourbon casks are made of American white oak, which has high level of vanillins that produce a vanilla flavour. That results as the flavour characteristics of bourbon cask whisky as vanilla, caramel, creamy and sweetness.
Sherry cask refers to the cask formerly contained sherry wine, which is a Spanish fortified white wine from Andalusia.
In the old times, sherry wine contained by European oak cask was often shipped around the world, especially in Scotland. Once the casks were emptied in Scotland, the casks would be sold to the distillers since the sherry producer didn’t want to pay extra fee to ship them back to Spain and the casks could be sold at a great price. Therefore, the sherry casks were reused in maturing Scotch whisky.
Sherry casks are made of European oak, which contributes flavour profile of tannin, resin, clove and dried fruits to sherry cask whisky.
Wine cask refers to the casks that formerly contained or aged wine, like Burgundy, Bordeaux red wine, Chardonnay etc. Whisky can be matured solely in a wine barrel or transferred into a wine barrel at a later stage of maturation and finished in the wine barrel.
When wine is held in casks, a small amount of wine soaks into the wood - so when that cask is refilled with whisky, the aroma and flavour of the wine seeps into the whisky over time. The whisky is usually aged for years before moving to the wine cask, so it is therefore 'finished' in the wine cask.
The wine characteristic of the whisky would generally be different depending on what sort of wine barrel was used for maturation. This a great way of adapting our love of wine or whisky and blending it with the whisky industry.
In recent years, many distilleries have been turning to new casks types since it is a great way to create new flavours without totally altering the original flavour. Wine casks are one of the recent popular choices.
FOR SINGLE - TASTING SET
A Highland single malt whisky primarily matured in ex-bourbon casks, to present the characters of bourbon casks.
Age: 14 years old
Strength: 46.0% ABV
Bottler: Original bottling
NOSING: Floral, vanilla, honey, spicy, slightly smoky
PALATE: Vanilla, oily, creamy, waxy, pepper, slightly brine, leather and malty
FINISH: Long sweet with peppery, oak and slightly dry
A Highland single malt whisky primarily matured in Oloroso sherry cask, to present the characters of sherry cask.
Age: 18 years old
Bottler: Original bottling (OB)
Cask Type: Sherry cask - Oloroso
NOSING: Sugary raisins, dried fruit, sherry sweet, dark chocolate, toffee
PALATE: Cinnamon, dark fruits, plums, chocolate, little bit spicy and leather
FINISH: Caramel, dry with grape-skin, a little mint and berry
A vatting of 1999 vintage whisky finished for 4 years in Clos de Tart Burgundy casks and 1995 vintage whisky finished for 8 years in sweet fortifed Côte du Rhône wine casks.
Companta, it’s a Scots Gaelic means “Friendship”. It is the 5th Glenmorangie's annually released Private Edition range.
Bottler: Original Bottling
Cask Type: Grand Cru Burgundy & Cotes Du Rhone
NOSING: Typical red fruit like stewed plums, dark leather and damp wood, milk chocolate and spice
PALATE: Sweet and spicy, old oakness, dark chocolate, overcooked cherries, hint of winey flavour like tannin grapes and leather
FINISH: Medium-long finish, sweet, oily and mouth-coating finish