A Reference Guide to Cask Shapes and Sizes

With Cask 88’s celebrated ability to take you, the cask owner, on a complete journey From Cask to Glass(™), we hereby include a pretty comprehensive list of different cask sizes and types to help inform you about which vessel will be the best choice to mature your own whisky. Some of these casks are commonly used, some are vanishingly rare – each one will mature liquid in a different way and result in a very different final whisky. 

Some general rules: A bigger cask will offer less surface area per litre of contained liquid, and will thus mature its contents more slowly. This also means the

rate of Angel’s share is reduced. It’s therefore wise to leave larger casks alone for longer periods of time. Conversely, it’s best not to take one’s eye off a smaller cask – the liquid might evaporate or become too woody in a much shorter time.

It’s not just oak wood in these casks. It’s exceptionally rare for Scotch Whisky to be matured in fresh ‘Virgin Oak’ casks – almost every cask we use will have previously been used as a maturation vessel for another type of alcohol. The flavours of whatever was in the cask before the whisky will have a greater or lesser contribution to the final flavours of the matured spirit. Some cask types are more likely to have a partnership with certain types of alcohol. Having a drink of bourbon, wine, sherry or cask ale can help you decide if those flavours are something you want in your whisky’s profile. Go on – it’s research!

 

Note: Despite being a very long list, all information presented below is a simplified version of reality – make sure to get the full story when speaking to your sales manager.

Casks Alphabetically (Click on a Cask name to jump to its entry)

Barrel	Barrique	Blood Tub	Butt	Cask	Demi-Satyr	Firkin	Gorda
200l	225l	40l	500l	N/A	333l	41l	700l
Hogshead	Kilderkin	Madeira Drum	Octave	Pipe	Puncheon	Quarter Cask	Rundlet
250l	82l	650l	50l	350l	500l	125l	68l

 

Casks by Volume:

Cask – N/A

 

Sometimes, people use the word ‘barrel’ as the generic term to describe any wooden vessel used to store alcohol. We forgive them… through gritted teeth. If you wish to talk about maturation vessels in the abstract, then the word ‘cask’ is your friend. It’s usable on everything on this list. A barrel is simply a very common type of cask, in the way that a Hoover is a type of vacuum cleaner. James Dyson is already incredibly tightly wound, ready to start spinning in his grave for every time someone has called one of his appliances a ‘Dyson Hoover’. Don’t be a corpse-spinner: choose your words with care.

 

Blood Tub – 30-40l

Ew, gross. Why is this called that? Wikipedia doesn’t even know… Don’t choose it, unless you’re happy being shunned.

More of a brewers choice, commercial whisky makers avoid this impractically tiny thing. Angels’ share on this tiny tublet is extreme. It’s been used as a transport cask in the past, as it’s small enough to strap to a horse and then transport the spirit, probably while trying to avoid any…imperial entanglements.

Firkin – 41l

A small cask that can mature whisky at a pretty rapid clip. Firkins were traditionally used to hold ale, but firkins seasoned with sherry, wine or dessert wine have all been used for whisky maturation. Distressingly, an old timey use for firkins was for the storage of fish, butter or animal fats. Be sure not to choose one of those, or you’ll be all like: ‘What’s that doing in my firkin cask?!’

Octave – 50l

Quarter the size of an American Standard Barrel, the Octave cask affords very speedy maturation times. Indeed, such is the rapidity of flavour development and alcohol evaporation in an Octave, these casks are almost always used to finish a spirit that has already spent time maturing in a Hogshead. Choose an Octave for potent oaky notes, introduced without delay!

Rundlet – 68l

Another in the ‘Olde English’ set of traditional wine and beer casks (evidenced by its awkward literage) – and a frontrunner for the name of my first child, the rundlet is the most fun cask type on this list to say over and over again. A useful cask size, no doubt – if you can find a rundlet to mature whisky it, it’ll likely turn out to be an exciting brew indeed. Springbank distillery worked that out in style. Rundlet, rundlet rundlet!

Kilderkin – 82l

Nice and simple, this is a double Firkin, the last in our trio of old British cask sizes. You might also expect a Kilderkin to bring hoppy notes to a whisky, since this cask size is the favourite standard of CAMRA: the Campaign for Real Ale. Otherwise it’s probably not much different from a Quarter Cask, but considerably more fun to say. It’s also the name of a fine whisky bar on Edinburgh’s Royal Mile.

 

 

Quarter Cask – 125l

As an octave is to a barrel, a quarter cask is to a butt. A smaller size means a quicker maturation, and more oaky, woody notes in the whisky. Quarter casks mature things at an intermediate rate and can be seasoned with other spirits beforehand. A good, flexible choice for the whisky aficionado, quarter casks also have the advantage of providing enough bottles to celebrate a large event in style, without having more leftovers to deal with than is reasonable.

 

(American Standard) Barrel – 200l 

America’s bourbon industry is doing very well, and local rules ensure that once a barrel has matured bourbon once, it can never be used for the same purpose again. This means that the USA is a great producer of casks made of white oak (Q. alba), which it exports to the rest of the world for all kinds of maturations – wine, sherry, beer; the ex bourbon barrel is a friend to all. When it comes to Scotch whisky, we like to rebuild ASBs into slightly larger Hogsheads (See: Hogshead), which impart the lovely oaky, vanilla, coconutty notes that only an ex-bourbon cask can provide.

Barrique – 225l

The French have many words for types of cask and this is the most impressive sounding. It may not be the largest of vessels, but the contents of a barrique are likely to have been a very impressive French red wine. Cognac is also possible. This can add considerable punch and tannin to the flavour of your maturing whisky, so an ideal choice for those looking to show off a bit. Ooh, la la.

 

Hogshead – 230-250l

This is an absolute classic – the most tried and true maturation vessel for a Scotch Whisky. Hogsheads are in fact American Standard Barrels that have been taken apart and rebuilt with more staves for capacity. The combination of bourbon whiskey and American white oak plays beautifully with maturing Scotch, giving rise to flavours like vanilla, coconut and wild flowers. For over 90% of whiskies, this is a perfect partnership, and the only maturation vessel they’ll ever need. But it’s also very common to start a whisky maturing for 8-10 years in a ‘Hoggie’ and then re-rack it for finishing in another cask type… See: all other entries in this list.

(Note – Sherry Hogsheads are also increasingly becoming a thing).

Demi-Satyr – 333l

Obscure whisky legends tell of an attempt at the Bowmore distillery in the 19th century to cooper a barrel that could safely trap and contain Old Harry himself. The final 666 litre cask, carved from black oak and charred with sulphur worked magnificently well, interring both the dark lord, and 666l of spirit that never matured, for no angel would take their share.

The presence of this evil cask so upset the islanders, that it was later taken apart and the staves split in half, rebuilt into two complementary 333 litre casks. This one, the ‘demi-satyr’ contained the goat legs of the great beast, and was sent to do work at Macallan distillery.

Nobody knows what became of the other half, but surely no good could ever come of reuniting this cask with its sibling. Instead, it can be used to slowly mature a surprisingly smooth whisky, with notes of liquorice, brimstone and century eggs.

Pipe – 350l+ 

This describes shape more than size – a pipe is a bit longer and narrower in shape, because that’s how they do things in the longest and narrowest country – Portugal (Chile tried to get in on the action, but nobody wanted to mature alcohol inside a drainpipe).

Since they are Portuguese in origin, pipes can be expected to be soused in rich Port wine, giving sweet, spicy, red berry or jammy notes to any whisky matured therein. Delicious and intense.

Butt – 500l

 

Hehehe – butt. Ok, now that’s out of your system: this is the standard unit of Spanish sherry maturation. Traditionally made of European Oak, but often seen built from American oak too, sherry butts are as varied as the sherries that Spain produces. From dry Finos, through well-balanced Olorosos, to sweet and sticky Pedro Ximenez, sherry butts give rise to excitingly varied and rich flavours in Scotch whisky, and have done so for many years. Scotch and Sherry are partners of many seasons, and their comfortable familiarity with each other really shows.

Madeira Drum – 650l 

An elite and rare cask choice indeed – Madeira drums are huge and squat, with a low centre of gravity, possibly to make them more stable when they used to mature Madeira wine on long, hot sea voyages. Madeira is unique among dessert wines for requiring hot and humid maturation, and the use of sessile oak (Q. petraea) in cask building. Stewed fruitiness and cinnamon spiciness are a hallmark of Madeira cask matured whiskies, often overlaid with sweet honey and caramel notes.

Puncheon – 500-700l

Very large and squat, with thick staves, a good puncheon can be an absolute chad.

There are two main types of puncheon, one is commonly used to mature sherry, the other is mostly used to mature rum. Either is a fine (though hard to find) choice as a vessel for whisky maturation. Sherry has already proven what a great partner it is to whisky and rum matured whiskies, though less common, have very dedicated followings. Brown sugar, spices and tropical fruits are wonderful hallmarks of a rum finished whisky. Let in the sunshine!

Gorda – 700L

Holy hell, this is an ambitious choice. Effectively meaning ‘the big one’ in Spanish, this is an abundance of cask. Difficult to move, difficult to char and difficult to fill, Gordas are only really used as blending vessels in the USA, since they can comfortably swallow the contents of three standard barrels. Hats off if you want to mature a copious amount of single cask whisky for an extremely long time in one of these. Best put it in your will for your grandkids.

 

Your Cask – Your Whisky

If you have a cask with us at Cask 88, then the fate of the whisky is in your hands. Most whiskies will be maturing in Ex-Bourbon Hogsheads as standard, but if you’d like to arrange a re-racking into another type of cask, then have a word with one of our cask managers. Have your own impact on a new whisky like nobody has experienced before. A great cask can make a great whisky – and the possibilities are limitless.