Distillation of Spirits
Dated February 18th 2000 Rev 2.1
Due to numerous responses and
requests, the following describes my procedures.
1/ Fermentation
Ferment a wash of 5-6kg cane sugar and 22 litres of
water with a yeast that has an alcohol tolerance of > 15%. Several kits are
available here that include a yeast nutrient. This is essential as it provides
the necessary substances for yeast cell construction which are present in the
typical brew ingredients, but as we are after a relatively pure substance, we
don't want to start with fruit or malt/hops. I will look up the specific
chemicals I use in my kits - it's something like ammonium sulphate and some
metal salt - probably sodium chloride but will have to check. Wine nutrients
available from any homebrew shop will probably do.
Typically produces a relatively flavourless 12% brew
Product currently in use here is called 'Turboyeast' from Alcotec in Sweden.
No address on packet, but product barcode is 7 391976 303701. Fermentation takes
3-5 days. Sachet contains 90g yeast and nutrient.
2/ Concentration of ethanol and elimination of undesirable flavours by any
of several distallation methods
I used to use a pot stil - It only holds
about five litres of wash at a time which was a pain, but adequate as I am only
producing for my own consumption. It has a standard 1.5KW jug element in it. I
use a Variac (a variable transformer) to reduce the standard 240V line voltage
to about 90 - 110 V which seems to produce a nice continuous simmer at about 4
amps. As the alcohol evaporates the vapour is condensed in a water jacket and
drips into a collection vessel.
Temperature control is electronic - a sensor
in the top of the dome lid attached to a digital thermostat to switch the supply
on & off to maintain temperature.
The still currently in use holds about 13 litres and does a brew in two
batches. Also with a 1.5KW element, but no need for the voltage control here.
Simmers happily with the full 240V.
Standard glass thermometer in the dome
to detect change points.
The first liquid to be condensed at about 75 deg C at the top of the still
(about 600ml for my 12l still) is known as the 'head' and contains most of the
methanol (toxic). This is put aside.
At a slightly higher temperature (84 to
91) the 'Body' comes off. This is substantially ethanol, but does contain some
impurities. Notably some aldehydes and ketones - the smelly bits that are a
byproduct of the yeast metabolism. This 'Body' proceeds to step 3.
Above
about 91C the evaporate contains the higher alcohols, other aldehydes and
ketones and generally nasty stuff that gives you chronic hangovers. Label it the
'Tail', add it to the head and add it all to your next 12 litres of wash in the
still (it still has a good amount of ethanol in it which would be a shame to
waste!) Stop collecting tail when the condensate becomes cloudy, or is mostly
water (about 95C)
Another method is freeze distillation - Decant your wash into 1.5 litre soft
drink bottles, freeze, then remove the liquid. Hint : cut horizontal V shaped
cuts in the bottle and wrap with a thin plastic wrap (to prevent leakage) and
freeze. Remove from freezer and spin with electric drill and collect product in
bucket. YMMV. Can't see how to separate various 'ols so I don't recommend this
method.
Fancy Retort stills have a cylinder of glass marbles which the vapors rise
through - water condenses on the marbles and drops back; alcohol rises through
to condensor.
3/ Treatment of produced spirit
It gets left on a 'primary treatment
carbon' for about a week. the carbon absorbs the smelly bits - the aldehydes and
ketones. Unfortunately, it also leaves the stuff a dirty grey colour (suspended
carbon bits) so onto the next step!
(Currently I use a fast treatment carbon
which is fine carbon powder in a sachet with water and treats a batch in 1 day.
The sachet need some firm massaging before opening as the carbon settles in the
sachet into a sludge which needs to be remixed with the liquid.)
4/ Filtration of produced spirit
A product sold as 'Secondary filtration
carbon' makes a fine filter for removing the grey colour. I used to use two soft
drink bottles with the bases cut off, inverted, with a small hole punched in the
lids, as filters. Wad a piece of loo paper or 1/4 of a paper towell into the
neck hard against the screwcap. Adjust density of paper so that water will drip
through at about 1 drip per sec. Put your slower dripper on top of the faster
dripper, a cup of secondary carbon in each bottle, and hang the lot over a
suitable collection vessell (I use a 5 litre glass carboy.) Fill top bottle with
treated spirit and leave overnight. If resulting spirit is not clear,
repeat.
Discard carbon after treating the output from your whole 23 litre
wash
New technique in use here now is a 5l plactic screw top container, plastic
hose, and screwtop tube inline which holds the secondary carbon and a disc of
filter paper. Manufactured locally by the homebrew shop.
5/ Watering down of spirit
Yes, you gotta do this! Don't drink it
straight - It'll make you go blind. It comes out of my still between 58 and 70%.
Get a spirit hydrometer and measure it. Water down to about 38%.
As an aside - here in NZ Alcohol content is measured as alc/vol and ALL %ages
mentioned herein are alc/vol. US uses alc/weight. Here in NZ, typical commercial
spirits are 37.5% (alc/vol)
I had a problem a few months back - People told me that my home brew spirits
were great, but very potent. I was erroneously measuring alc/weight and thinking
it was alc/vol. Hence, my spirits which should have been 38%alc/vol were around
38%alc/weight which was sorta like 47%alc/vol!! Beware!
6/ Flavouring of spirit
My favourite homebrew shop has an extensive
collection of spirit and liqueur flavourings. All have instructions on them re
quantities required. Some 50ml bottles make 1.125 litres, some 2.5 litres.
Liqueur flarourings typically call for added water, glucose and cane sugar and
make a 750ml bottle.
You can of course create your own flavourings - try a
dozen cherries in a bottle of 38% for a few months. I have used commercial
essences and also reduced fruit mashes to jam for flavouring. Experiment. You
will probably need a substantial amount of sugar to make a liqueur drinkable,
and the liquid glucose to give it some texture. Some use glycerine for thickness
and smoothness, but I'm not keen on glycerine in beverages. Propylene Glycol is
used in some commercial essences : I tend to avoid that substance too!
7/ Consumption of finished beverage! (hic)
Well, what can I say? Don't
drink and drive!
Glenn McAllister, ZL2TLD
Delta-Wye Electronics
Wellington
New
Zealand
email:delta@ihug.co.nz
Phone +64-25-432883 (Cellphone - if it's off, I'm asleep!)