By seasoning an oak cask with a conditioning liquid, the scene is set for the final journey of a fine spirits maturation – it’s cask-finishing.
The beauty of cask-finishing is that it is naturally innovative. There are no hard and fast rules for matching conditioning liquids and whiskies. However, there are a number of tried and trusted combinations that are natural flavour pairings.
Make it cask-strength whisky
Firstly, it is highly recommended that whatever type of whisky is used in a finishing cask, it should be of cask-strength.
A cask-strength spirit has the same alcohol by volume (ABV) as it had when it was removed from the maturation barrel. This means it has not been diluted with water and typically has an ABV between 55 and 65%. Cask-strength spirits are often more intense and flavourful than their diluted counterparts, as the higher alcohol content preserves more of the natural flavours of the spirit.
In a finishing cask, the higher alcohol content of cask-strength whisky allows for more interaction with the barrel’s wood. This can impart additional flavours and aromas to the whisky.
Classic conditioning liquids for cask-finishing
Fortified wines are the classic conditioning liquid for whisky, as they impart a natural richness and fruitiness.
Casks seasoned with Oloroso sherry are the most common type of cask used in scotch whisky finishing as they are the most versatile and great for finishing all whisky styles ( as well as rum and cognac). Oloroso imparts deep dried fruit notes like figs, dates, spice, and nuttiness.
Pedro Ximenez (PX) is a sweeter sherry than Oloroso. Casks seasoned in PX are fantastic for finishing robust, heavily peated Islay whiskies and oaky Bourbon and Ryes.
The additional sweetness rounds off the phenolic notes of peated whiskey, producing a beautifully balanced spirit. Also, PX is the best choice if you prefer rum on the sweeter side.
Of all the different types of port, Ruby Port tends to be most used in whisky finishing. It leaves a residue of red anthocyanin pigment ingrained in the barrel’s wood that is transferred to the spirit during finishing. In addition to a red hue, Port will deliver a flavour of forest berries with dark chocolate and a fragrant character. Port compliments elegant spirits such as Cognac and Speyside malts.
Madeira wine is heated while ageing, unlike sherry, which results in caramel, dried fruits, and baking spice notes, with a vanilla aroma. Compared to sherry and port, finishing spirits in Madeira casks is less typical, but it’s becoming increasingly trendy. Spirits matured in Madeira casks take up the subtle but sophisticated aromas of spice and fruit of the Madeira Wine. It is a natural finishing choice for smooth, light floral spirits such as Cognac and Lowland malt whisky.
Matching conditioning liquids and whiskies: recommended pairings for cask-finishing
Lowland Malt and Irish Whisky
Pair with Oloroso or Madeira seasoned casks. These conditioning liquids both work well with light and floral whiskies.
Pair with Oloroso. This is a classic conditioning liquid for finishing Speyside whiskies.
However if a Speyside malt has already been matured in an Oloroso cask, finishing in Port or Madeira will add an additional layer of complexity.
Pair with Pedro Ximenez sherry (PX). The additional sweetness rounds off the phenolic notes of moderately peated whisky, producing a beautifully balanced spirit.
If the Islay is lightly peated, pair with Madeira, which provides a better balance and is less sweet.
If the whisky is heavily to moderately peated it is best paired with Pedro Ximenez sherry (PX).
For lightly peated Highland Malts, pair with Oloroso, Ruby Port or Madeira.
Best paired with Madeira or Ruby Port as the whisky benefits from red fruit notes.