What is whisky?!


Single Malt Scotch whisky


A lot of effort is involved in turning the freshly harvested barley into a Single Malt whisky. Whisky is made out of only 3 ingredients, water, yeast and barley. Before this can become whisky, we first need to turn it into an alcoholic spirit (through distillation) and mature it for at least 3 years in oak barrels.
The entire process can be roughly divided into 6 stages:
  • Malting
  • Mashing
  • Fermentation
  • Distillation
  • Maturation
  • Bottling



Every grain of barley contains, amongst others, starch and enzymes. During the malting stage we imitate the natural germination process of the barley. This is to turn the starches into sugars.

Laphroaig Malting Floor
1 - Malting floor at Laphroaig

The barley is soaked for 2 or 3 days in water until it has reached a moisture level of approximately 40%.
The wet barley is then laid out on a malting floor where, under the influence of heat and humidity, the enzymes are activated that will turn the starch into sugars.
The malted barley has to be dried afterwards, to stop the germination process. This can be achieved in various ways, for instance using a coal-, or peat-fired kiln underneath the malting floor. Nowadays the malted barley is often dried using hot air.
The way in which the malted barley is dried can have a lot of influence on the nose and the taste of the whisky. For instance, on the Scottish isle of Islay, barley is mostly dried using a peat-fired kiln, which gives the whisky a smoky character.




After the malted barley is dried, it is ground into a coarse flour we call grist. The grist is then put into a large metal container, the mash tun, where it is mixed with hot water in several stages, varying in temperature from 60 to 90°C. During the mashing, the enzymes in the barley will convert the starch into soluble sugars. The resulting product is called wort.




The wort will now be pumped into a large wooden tub called a wash back. These huge wooden tubs can easily have a content of 80.000 liters. Inside the wash backs yeast is added to the wort, which causes the sugars to be converted to alcohol. This procedure takes about 48 hours, and afterwards we are left with a brown liquid of approximately 8% alcohol. (wash)

Washbacks van Lagavulin
2 - Wash backs at Lagavulin




Distillation takes place in a large copper still, called a Pot Still. Scottish whisky is traditionally distilled in 2 stages. The wash is pumped into the wash-, or low wine still where it is, in most distilleries, heated with steam. Because alcohol has a lower boiling point than water, the alcohol evaporates first and rises up to the swan neck, and flows into a condenser where the alcohol vapors are condensed into a liquid spirit of approximately 22-25% alcohol. This 'low wine' is then transferred to the second pot still, called the 'Spirit Still', where the distillation process is repeated. From the condenser of the spirit still, the alcoholic spirit is led to the 'Spirit Safe'. In the spirit safe we separate the first, and last cut (head=toxic methanol and tail=mostly water) from the middle cut (heart). Head and tail are added to the low wine for the next distillation run, which leaves us only with the heart. This colorless spirit of approximately 70% alcohol ('new made spirit') is then stored in the spirit receiver for the final stage of whisky making.

De koperen stills van Glenfiddich
3 - Stills at Glenfiddich




The new made spirit must be matured for at least 3 years before it may be called whisky. During maturation the whisky gets its color and 60% to 70% of its aroma's. Maturation is generally done using one of two types of oak barrels (or a combination): American Oak (ex-bourbon casks) or European Oak (mostly ex-sherry or port casks). Whisky matured on sherry casks or port pipes usually have a darker amber color and sweet, fruity and nutty flavors, whereas bourbon casks give a lighter golden color and vanilla flavors to the whisky. Oak barrels have a lifetime of about 65 years, so they can be reused. These reused barrels are called second- or third fill barrels/casks. The casks are stored in warehouses where they age for at least 3 years, but often longer.

Warehouse bij Balblair
4 - Balblair warehouse




After years of maturation and regular inspection, the Malt Master decides which barrels are ready for bottling. The whisky is then filtered and often diluted with spring water to achieve 40% or 43% alcohol. The alcohol percentage may vary between distilleries or even between multiple whiskies from the same distillery, but it has to be at least 40%. Some whiskies are bottled without being diluted first, we call these Cask Strength whiskies.

Laphroaig 10yo Cask Strength
5 - Cask Strength Laphroaig

© Copyright Enrico Klein / Dramtime