154 distiller
Stripping is the process used to separate the alcohol from the
water in grain fermentation's "beer," or in the case of molasses,
"dead wash." Different terms may be used for other substrates.
In the case of beer, it contains spent yeast, grains, (except in the case of malt whis-
key) congeners and alcohol. A stripping still should only remove the congeners and
alcohol; fractionation of the volatile compounds — of which there are many, each
with different boiling points — is not the objective.
ere are two different stripping methods used in the industry: batch, or pot, strip-
ping and continuous, or column, stripping.
POT STILL (BATCH) STRIPPING
A pot distilling system consists of a boiling kettle heated with steam in various ways
(not usually direct injection) or with an open fire under the pot, in the traditional
method. e vapor containing the volatile components and some water is then con-
densed. In the case of pots heated by open fire, the condenser should be in a separate
building to avoid contact with the fire. In the old days the pot was referred to as
an alembic.
is no-reflux system can produce a low wine with about 35% alcohol. is will
require a second distillation in a spirit still (also a pot) or hybrid still, with a column,
to produce the desired spirit for consumption.
It is not practical to provide reflux — a process that enhances the volume of alcohol
in the distillate — but some refluxing does occur when the vapor hits the inside of the
vapor pipe that leads to the condenser. e lyne arm can also be sloped back to the pot
to allow condensed liquid in the arm to reflux (flow) back into the pot. is re-boiling
of liquid actually enhances the strength of the distillate, if only marginally.
Another method is to install a cooling jacket around the swan neck, which will con-
dense some vapor before it gets to the lyne arm, thus causing internal reflux. is can
produce a low wine with up to 40% alcohol, but the distillation will be slightly longer
The Principal Features
of
Stripping Stills
Michael Delavante
Illustrations by Francesca Cosanti
