What is whisky made of?
A quick guide to whisky knowledge
Whisky is made from grain, water and yeast. These are the basics. Then comes aging.
It comes from a variety of different grains indeed: Barley, Wheat, Corn and Rye can all be used to make whisky or whiskey.
Anyway, always remember that grain is just the first step: the road to the final spirit is a long and winding one.
Each grain produces a different style.
Barley is the grain traditionally used to make beer. With malted barley you can make malt whisky. Single malts are all made from malted barley. Pot still Irish whiskey uses a part of malted barley and another of unmalted barley in its making. Some malt is included in varying proportions in blended whisky too.
Wheat is used either to make single grain whiskies or blended ones. Single grain whiskies are typically distilled in a column still rather than a pot still. Blended whiskies are made by blending different whiskies together: wheat whisky can be used as a base for the blend, while single malts are added to give full character to the spirit.
Corn is used in bourbon as the core of the fermenting cereals. Rye or Wheat are also used in bourbon production, as they give extra flavors to the finished spirit.
Rye whiskey is typically made in the US or Canada. Other grains can be used in addition to rye; rye gives a special spicy flavor to the final product.
Water is another major ingredient in whisky making. A distiller needs a lot of water to keep the distillery running: this is why all distilleries are built next to a consistent source of clean water.
Water is used to soak the barley for malting. It is used to cool down the distilling vapors and turn them to liquid again. Alcohol strength is often reduced with water.
Yeast eats the sugar in the fermenting liquid (the wash) and produces alcohol, carbon dioxide and heat. In the process it develops a range of flavors (usually fruity ones) which might survive distillation and go into the spirit. Some distilleries use unique yeast strains to make their whisky: they believe it yields specific flavors and character to the finished product.
Whisky must be aged in wood. Usually oak casks. The new make spirit coming out of the spirit still it’s not whisky. Not yet, at least. Regional and national regulations may vary, but everywhere whisky must stay some years in wood. Scotch must be aged for at least three years. Usually it rests in oak casks for much longer.
Aging is paramount. During maturation some bad flavors of the spirit are lost through evaporation, while others are yielded by the cask. Oak casks often impart vanilla or caramel. They can also release tannins and give some astringency to the mature spirit.