Whiskey has been made for centuries. Naturally, over that time the process has changed. But, as you will see far less than you would think. If you want to know how whiskey is made just read on.
We take you through the whole process and explain how it has changed over the years.
How is Whiskey Made in the modern world
This first process is how all whiskey starts out. It is the same regardless of what grain is used.
The malting process
Malt whisky production begins when the barley is malted – by steeping the barley in water, and then allowing it to get to the point of germination. Malting releases enzymes that break down starches in the grain and help convert them into sugars. When the desired state of germination is reached the malted barley is dried using smoke. Many (but not all) distillers add peat to the fire to give an earthy, peaty flavour to the spirit.
Today only a handful of distilleries have their own malting. These include Balvenie, Kilchoman, Highland Park, Glenfiddich, Bowmore, Laphroaig, Springbank and Tamdhu. Even those distilleries that malt their own barley produce only a small percentage of the malt required for production. All distilleries order malt from specialised malters.
The Milling process
The malted grain is further checked for any rootlets, stones or other impurities before being milled. The powerful grinders of the milling machine generate considerable friction and heat, and a fragment producing a spark could cause an explosion (the fire that destroyed part of the distillery in 1898 began in the mill room).
The malt enters the milling machine at the top and is then crushed and ground by a series of rotating millstones. The powdered grain that emerges at the bottom, called grist, moves on to its rendezvous with that other vital ingredient, spring water.
The ground malt (or grist) is mixed with very hot water and directed into the mash tun. This is a large, circular, covered vessel with a rotating rake-like attachment, which stirs and breaks up the thick porridgy substance, now called mash. The process takes around six hours.
The combination of heat, movement and moisture extracts the sugars from the grist, dissolving them in the water. This sugary liquid, called wort, is drained off and transferred to the wash back for the next stage: fermentation.
The Magical Fermentation Process
The sugary liquid or wort that is drawn off from the mash ton (leaving the draff behind to be used as cattle food) is cooled before passing into the wash back, a large, circular stainless steel vessel. Yeast is added to the mix, attacking the sugar in the wort and transforming it into crude alcohol.
The process is an extremely active one, with the wort heaving and bubbling like the contents of a gigantic magic cauldron. Gradually the vigorous movement dies down and after some 46 hours the fermentation is over, producing a beer-like liquid known as wash. This contains alcohol of low strength (along with some un-fermentable elements) which is piped through to the still room.
In the first of two distillations the fermented liquid, or wash, is piped through to the wash still. There it is brought to boiling point by means of steam-heated coils. As the wash boils the alcoholic content vaporises, passing up the neck of the still and along the lyne arm, before being condensed back into liquid form by the cooling system beyond.
This first distillate, known as “low wines”, is collected in a receiving vessel and then run off into the spirit still, where the distillation process is repeated more slowly. The flow of raw spirit that emerges is divided into three parts. The first, called “fore-shots”, contains oil and other impurities. The second and purest, the “centre cut”, is collected to become whisky.
Finally comes the “feints”, the back end of the run, which together with the fore-shots is returned to the process to be re-distilled with the next batch of low wines.