How Scotch whisky is made

By law every drop sits in oak for at least three years, and a typical single malt spends 10 to 15.

stations: 7
things upstream: 44
raw sources: 19
steps from the ground: 6

The short version

Malt Scotch is made from malted barley and water. The barley is soaked and germinated, dried over heat or peat smoke, mashed with hot water, fermented with yeast and distilled in copper stills. Grain whisky comes from column stills, and most blends mix the two. All of it must mature in oak in Scotland for at least three years.

Soak and sprout the barley

Barley is soaked in water for two to three days and allowed to germinate. Sprouting releases enzymes that turn starch into fermentable sugar. After three to five days, hot air halts the germination.

Goes in
Barley Water
Dry over peat smoke

Hot air stops the sprouting, and in many cases smoke from a peat fire is added during the heating for phenols that give a smoky aroma. Islay malts have a reputation for being the peatiest.
Mash with hot water

The malt is milled into coarse grist and mashed in a large kettle called a mash tun with three portions of hot water, at about 60, 72 and 88 degrees Celsius. The sugary liquid is called wort.

Goes in
Water Malted barley
Ferment in the washback

Yeast is added to the wort in a large vessel called a washback. Within about three days the liquid reaches 5 to 7 percent alcohol and is known as wash.

up to 3 days

Goes in
Baker's yeast
Distill in pot stills

The wash is distilled in copper pot stills twice, sometimes three times. The first pass gives low wines of about 20 to 30 percent, and the second gives new make spirit of 60 to 70 percent.
Mature in oak casks

The new spirit is diluted to about 60 percent and put into oak casks, often ones used before for American whiskey or sherry. Scotch must mature for at least three years, and a typical single malt spends 10 to 15.

at least 3 years

Goes in
Oak wine barrel
Vat, dilute, bottle

Whisky comes out of the cask at around 60 to 63 percent. Water is added to bring it to a bottling strength usually between 40 and 46 percent.

Goes in
Glass bottle Water

End of the lineScotch whisky

Worth repeating

The earliest written record of Scotch distilling is a 1494 note that eight bolls of malt were given to Friar John Cor to make aqua vitae.
Aeneas Coffey patented a column still in 1831 that let distilleries run continuously.
George Smith took out the first distillery licence under the 1823 Excise Act and founded Glenlivet in 1824.