The Whisky Production Process
First, top-quality barley is steeped in water and then allowed to germinate. During germination, the grain slowly changes into malt where the starch in the grain is made ready to be converted into sugars in the mash tun. Drying in a kiln stops the germination process. At the kilning stage, the desired level of peating for each individual distillery is carried out.
The malted grain is crushed and mixed with hot water into the mash tun. The sugar is run off in liquid form, called wort.
Fermentation
The wort is cooled and then pumped into fermentation vessels called washbacks where yeast is added and the fermentation process starts. The yeast converts the sugar into alcohol. After 2 – 3 days fermentation is complete, leaving a liquid called wash which contains 8-9% alcohol by volume.
Distillation
The wash is distilled twice. The first wash distillation produces a liquid with a low level of alcohol known as low wines, which is then re-distilled in the spirit still. During this second distillation only the pure centre cut, which is about 65% alcohol by volume, is collected in the spirit receiver.
Pot Stills
Curiously, the shape of the pot still significantly affects the character of each malt whisky.
The entire product from the distillation is passed through the spirit safe to allow the stillman to check the strength and quality of the spirit.
The newly distilled, colourless spirit is filled in oak casks, while maturing the Whisky becomes smoother and more flavoursome and draws its golden colour from the cask. By law the whisky must be matured for a minimum of three years, but most single malts lie in the wood for 8 years or more.
Each bottle of single malt whisky is the product of a single distillery.
