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How do they

mal<e whisl<y?

Discover the complex,
multi-stage process involved in
making tfiis age-old alcoholic drin

Are there different types of he firstmain stage ofwhisky are disposed of and the wortis sent for
production is malting, a process
fermentation in a series of wooden
nuclrreac Tof soaking barley in water for containers called 'washbacks'. After two
days. This increases the moisture to three days in a washback, the wort
The most common design is the pressurised water reactor (PWR). PWRs content of the grains and causes generates a low-alcohol liquid, know as
I use pressurised water both as a moderator (the material that slows
down free neutrons, increasing the rate of fission reactions) and as a germination, which converts the starch the 'wash'.
coolant (the substance that transfers heat away from the reactor core to in the grains into fermentable sugars. Distillation follows, a complex process
the steam generator). Another common design, the advanced gas-cooled The grains are then separated from the of evaporation and condensing of the
reactor, uses graphite as a moderator and carbon dioxide as a coolant. The
chief advantage of this design is that it's possible to heat carbon dioxide to heated water and dried. wash in stills. This enriches the alcohol
higher temperatures than water (about 650°C vs 325°C). The greater heat Next, the dried malt is crushed into content of the wash and produces a
capacity greatly improves plant efficiency. grist and added to water, heated to 6ooc high-alcohol liquid that can then be
in a mashing process. This step creates a matured into drinkable whisky. Finally,
Advanced gas-cooled reactor (AGR) sugar solution (wort), which is then maturation is achieved by depositing the
Fuel element separated from the grains. The grains young whisky into oak casks.
Re-entrant gas Boiler
2. Vapour 4. 1mpure
Vapour is carried to a second column, the Low-alcohol content vapour and impurities are
'rectifier'. Deposited into the cool top of the evaporated at the top of the rectifier, before
column, it condenses and falls through being dumped back into the analyser. These go
perforated copper plates, re·heating as it up through the column and condense back into
gets to the heated bottom. liquid form. This waste is then siphoned off.

Graphite Diagrid Concrete pressure
core vessel l. Wash
The culmination
of fermentation is
Pressurised water reactor (PWR) the 'wash', a
liquid of
Steel pressure vessel Heat 5·8 per cent
exchanger alcohol. This
enters the still's
first column and
Pressuriser
drops through
levels of steam,
evaporating
into vapour.
3. Enriched 5. Liquid
At each plate, parts of the condensing liquid The remaining alcohol·rich liquid is drawn out through
reach their transition stage, returning to the bottom of the rectifier. Only the 'middle cut' of this
vapour, while others with lower boiling points spirit goes on to filling and maturation, with the initial
progress downwards. Turned vapour is 'foreshot' and 'tail cuts' diverted back into the stills. The
enriched by the higher alcohol content liquid. middle cut has an alcohol content of about 75 per cent.
'' Maturation is achieved by depositing
Circulation
pump
Fuel elements Control rods
Concrete shield the young whisky into oak casks''

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