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This is the second article in
a small series on Scotch Whisky- its origins, its production and
some of its mysteries. |
by David Rice
Following brewing, the next stage is where the whisky making
pro-cess totally differs from beer making; Distillation. Malt
whisky is distilled twice in stills which resemble huge copper
kettles. They are called Pot Stills. It is argued that only a
true Scotch malt can be made by distillation in pot stills. The
shape of these pot stills varies from distillery to distillery.
This is the one piece of equipment that the distiller will not
change, unless it is absolutely necessary. In fact, it has been
known that the pot stills would be patched up time and time
again. When it became necessary for a new still to be installed
the shape of the replaced still was copied, even down to the
patches and dents. Such was the belief that the shape of the
still produced a unique product. Evidence of this can be found
in the variety of whiskies produced from the same ingredients in
a similar process but having a completely different result.
The vapours produced by heating the wash in the Wash Still are
passed through a condenser which has cool water running through
it. The first distillate is called Low Wines. The low wines are
then passed to the Spirit Still. This still is normally smaller
than the wash still. This is because the bulk of the liquid has
been reduced. The spirit still is a similar shape to the wash
still, however, the remaining liquor in the wash still, known as
Pot Ale or Burnt Ale, is usually used as animal feed.
From this point the spirit produced is subject to duty,
therefore, all equipment is made tamper proof. The stillman
must, however, be able to determine the strength of the liquor.
This he does in the Spirit Safe. The spirit safe is a glass box
which is locked but through which he can see the hydrometers
during testing.
A Condenser where the distillate is
cooled. Note the oak barrels in the foreground.
As the spirit from the spirit still condenses, different
portions or fractions of it are separated and collected. This is
the point where the future of the distillery is in the hands of
one man. It is the skill and experience of the stillman to know
when to take that middle cut or heart of the run. It cannot be
done by taste or smell. It depends on the unerring eye of the
stillman. One error of judgment could impair the final product -
an error that might not become apparent until years later during
maturation.
The first raw runnings are known as Foreshots. The last runnings
are known as Fients. They are both fed back for redistillation
with the low wines.
The next stage is one of the most important and that which most
of all distinguishes Scotch from other like products. The
process is called Maturation. The new spirit is poured into oak
casks. These casks allow the spirit to breath and some
evaporation to take place. In fact, the equivalent of 27 million
bottles are lost to evaporation each year. This is known as the
Angel’s Share (Happy angels look after Scotland).
By law, in order to be called “Scotch” the spirit must be kept
in the cask or barrel for a minimum of three years in Scotland.
It has been proved that location can play a significant part in
the maturation process.
The Pot Still where the distallation
process begins. The shape and size of the Still is important in
the overall quality of the final product.
The climate may well affect the volume and strength of the
whisky too. A whisky which is matured in the damp misty islands
of Islay or Skye will lose strength more quickly than volume.
Con-versely, a whisky which is matured in the dry atmosphere of
Speyside will lose its volume more quickly than its strength. It
is generally considered that the longer you leave whisky to
mature in the cask the more mellow the whisky produced. The
harsher alcohol’s are tem-pered. However, this process only
lasts for about eight to twelve years. The longer in the cask
beyond this time only imparts flavour or colouring from the
wood. This is preferred in some whiskies and will obviously
depend on the type of cask used. Whisky when first produced is a
clear liquid. It is during maturation that the colour is
imparted to it. Oak casks that have previously contained sherry
give a splendid mellowing effect to the maturing whisky. In new
casks a woodiness can be imparted. Whisky matured in new casks
will have a slight straw colour. In casks previously used for
sherry it is the sherry soaking back from the wood into the
spirit that traditionally has given Scotch whisky its golden
colour. The original colour of the sherry is also important.
Refill casks are also used so that a more delicate colouring
will be imparted the second time.
The Stillman at work at the Spirit
safe. It is his expertise that ensures the future of the
distillery and the quality of the Whisky.
Casks have for a long time been in short supply so certain
whiskies are matured in wine casks or bourbon casks from
America. The Macallen prides itself on using the traditional
sherry casks from Jerez in Spain. In fact, they actually buy the
casks for them and let them use the casks “free of charge” as
long as they have them returned for use as maturation casks for
whisky. The average size of cask is a hogshead (approximately
250 litres - 55 gallons). Butts are also used which are twice
the size of a hogshead. Barrels are 500 litres (40 gallons).
Whisky when distilled has a strength of 115 to 120 proof. The
proof means “of tried strength and quality”. The problem was how
to define it. The old method was to dampen gun powder with it
and apply a light to see if it would still burn. Thus “proving”
it. With the advent of the hydrometer it is proven by specific
gravity. The temperature of measurement is 51 deg F.
The formula is quite complicated but in short is “proof spirit
is that which at 51 deg F weighs twelve-thirteen’s of an equal
volume of water at the same temperature”. More use-fully, a
spirit which contains 57.1% of alcohol by volume or 49.28% of
alcohol by weight. This is British proof. In the USA, proof is
recognised as 50% of alcohol by volume at 60 deg F. This means
that British proof (100 deg proof) would be 114.2 deg proof in
the USA. This has led to some problems when Americans visit
overseas and believe that they are drinking a “weaker” spirit
than they are used to. A Scotch in the USA will have a proof of
86.8 deg proof USA, whereas, elsewhere Scotch is usually 70 deg
proof British Standard. Today the proofage has been dropped from
the labels and has been substituted instead with the actual
volume of alcohol. The standard is 40% with 43% being used for
the USA market.
Water is added to the distilled whisky to bring it to a proof of
110 deg before being run into the casks. Finally, after
maturation the whisky is bottled. The bottling strength is 70
deg proof (40% by volume). Water is added to reduce the cask
strength to the bottling strength. The quality of the water used
in all these operations is extremely important.
Whisky does not mature in the bottle
Next week: Grain Whisky, what it is. Also the different types of
whisky and the main production areas of the Single Malt.
