Shortcut: sherry casks
Name: sherry casks.
Age: As old as Christmas itself.
Ah, Christmas. Well, yes, but that’s not really the point.
Oh. What is the point? Sherry casks.
Right. And they are? You know, whiskies either aged or finished in casks which have – for some time – previously held sherry. Sherry being the fortified wine, made mostly from the Palomino grape.
Got you. Sherry; Oloroso, Fino, Manzanilla, PX… All words you’ve seen on whisky labels signalling quality but never really understood, right?
You got me. Honestly, you’re not the only one. Let’s start with Fino and Manzanilla which are essentially the same thing. Manzanilla is just Fino specifically from Sanlúcar de Barrameda, the city which is part of the autonomous community of Andalucía in southern Spain.
Interesting. What else is there to know? Fino is produced from the first very gentle pressing of the grapes, fortified to about 15% ABV. It develops under a layer of yeast, FLOR, so no oxygen is in contact with the wine. Meanwhile oloroso is produced from the second pressing and fortified to above 17% This prevents FLOR forming and oxidation makes the wine darker.
And PX? Pedro Ximinez, the type of grape used to concentrate sugar levels. PX is used to sweeten Oloroso and is often sold as cream sherries or poured over ice cream.
Like a Solero? No. Solera, on the other hand, is a system for aging sherry and other fortified wines.
Anything to do with Wall’s (ice cream)? Again, no. More to do with the floors which are usually earthen. Solera literally means bottom. Basically, younger wines in upper rows of casks are used to top up casks of older wines stored below in order to produce a consistently aged blend.
Clever. Quite. Casks in the bodega tend to be stored three-high. The proportion for oloroso sherries and wine for bottling is removed from the lowest level, about 30%. These casks are then topped up from the middle level, which is in turn topped up from level one which is then filled up with new wine.
What should I know about the casks? They will be American oak and relatively inert in terms of extraction from the wood. They would not be any good for whisky maturation, so while a handful of brands may adopt the solera system for some or all of their maturation, the actual casks used in the sherry solera system will not be reused for whisky maturation.
OK. And what exactly is the whisky industry looking for from a sherry cask? Merely a cask with a good amount of wood extractives available.
It’s always about the wood isn’t it? Yes. Specifically, oak. Sherry removes some of the less desirable components from the wood initially but has little influence on the whisky maturation. Historically, sherry for bottling in the UK was delivered in Spanish oak casks (not part of the Sherry production routine). In the 1950s, however, Spanish legislation changed the way bodegas distributed the drink.
How so? Sherry must now be bottled in Spain so casks are built for the whisky industry and seasoned with wine for some time before being shipped to Scotland for whisky maturation. They are either Spanish or American oaks, as defined by the purchaser.
What’s the difference? Once upon a time, American oak would not have been routinely available. The warehouse system used for these casks would be dunnage or, more recently, racked. After the desired time, they would be emptied and then shipped to Scotland.
When a cask arrives from the bodega, how do you know it’s of a decent quality? You don’t. There’s no real way of knowing how good (or bad) it might be at giving cask extractives. The distillery will typically try a sample after 18 months and grade accordingly. When the cask is emptied, a judgment will be made on refilling based on the maturation of the whisky.
That’s a slow process. That’s Scotch. Only time ever tells.