On a recent visit to a bodega in Jerez, the winemaker joked that he was on his guard for Scotsmen looking for butts to pinch. Readers hoping for a column full of smutty jokes will be disappointed. I am referring of course to 500-litre sherry barrels, known as butts or, in Spanish, botas, and these Scots were respectable whisky distillers.
Scotch whisky is always matured in old barrels. Originally this would have been a matter of expedience. Most drinks in the 19th and for much of the 20th century were shipped in wooden casks so there would have been a surfeit of empties. Distillers bought them cheap and discovered that the seasoned wood improved their whisky. Claret, rum, madeira and brandy barrels would all have been used, but one drink in particular achieved a magical symbiosis with whisky – sherry. In 1864 William Sanderson, a whisky blender, wrote: “it is well-known that whisky stored in sherry casks soon acquires a mellow softness which it does not get when put into new casks”.
This went on merrily until the 1970s, when a law was passed decreeing that all sherry had to be shipped in bottles. The supply of butts dried up. There was panic on the streets of Dufftown. True, Bourbon barrels were still plentiful and cheap – Bourbon by law can only be aged in new casks – but for many whiskies the sherry character was essential. Glenfarclas, for example, use only oloroso or fino sherry butts. To begin with, desperate distillers scoured Britain buying up redundant casks from wine merchants, pubs and breweries, but these became increasingly hard to find. And so intrepid Scotsmen went to Jerez to see if the Spanish would sell them their butts.
It’s rare that sherry producers have spare barrels – they are all used for maturing sherry and rarely changed, so distillers have worked out a way to acquire the necessary wood. “Macallan own butts which are then loaned to sherry companies, and seasoned with wine to their exact specifications,” whisky writer Ian Buxton explained to me. The wines used in the seasoning process are then too oaky to be sold as sherry, so are either turned into Brandy de Jerez or vinegar. So you have a peculiar system where distillers buy barrels, store them with sherry bodegas, who sacrifice some of their wine to season the wood, before the now-empty butts are shipped to Scotland. After the whisky has absorbed enough sherry character, these casks can then be sold to, for example, rum distillers who also need seasoned barrels. You end up with a palimpsest of flavours. Each sip is a history of Britain’s insatiable alcoholic curiosity. You can see why the Scots are so keen to get their hands on those big Spanish barrels.
• Henry Jeffreys’ first book, Empire of Booze, will be published by Unbound in 2016. @henrygjeffreys
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