Whisky Magazine Issue 61
This article is 10 years old and some information provided may be time sensitive. Please check all details of events, tours, opening times and other information before travelling or making arrangements.
Copyright Whisky Magazine © 1999-2017. All rights reserved. To use or reproduce part or all of this article please contact us for details of how you can do so legally.
In the latest in his series defining whisky terms Dominic Roskrow looks at the letter C
Barley, yeast and water may be whisky's raw ingredients and the skill of the whisky maker and distiller may be crucial in placing the foundations of a great single malt. But it is two c words which steer the new make spirit towards its final taste destination – casks and charring.
Whisky of all types has to be made in oak barrels and there are two principle sources – American oak and European oak. The vast majority are American and are used first for bourbon and then passed on to distilleries in Scotland, Ireland, Japan and elsewhere.
Under American law, a cask may only be used for whiskey production once and then it must be discarded. For this reason there is a ready supply of cheap bourbon barrels – they cost about one tenth the price of a European sherry cask.
Before an American cask can be used for American whiskey it will be charred. There are different grades of charring from a light toasting to a deep and heavy burning. The process releases vanillin in the wood and helps expose the liquid contents to tannins, wood extractives, hemicellulose and lignin.
It is from these that a complex set of chemical reactions takes place.
In broad terms three things happen: the wood gives the whiskey its colour and up to 80 per cent of its flavour; the wood extracts some flavours and impurities from the whiskey. And the whiskey and the wood react together to form new flavours.
When the cask is emptied of American whiskey and sent to a country such as Scotland to be filled w...