Notes from 'Nekodificirovannye spirtnye napitki'
Until the abolition of serfdom in 1861, vodka production in Russia
was of a high quality but production was inefficient because the
materials and labour were free. A 1200 litre mash contained 350kg of
grain, malted rye grain, and 20kg of yeast. The first distillation
produced 40 litres of 'khlebnogo vina' (grain wine). Then milk was
used as a fining agent and a second distillation produced 20 litres
of fine spirit. After filtering it was diluted to 20-30 litres.
From the 18th century birch, linden, beech and oak charcoal was used
to filter vodka. Also freshly baked rye bread was used to filter
vodka, and egg white and milk were used as fining agents. Sometimnes
chill filtering was practiced - the barrels were left to freeze and
the ice together with the congeners was separated. It was
called 'russkoi vymorozkoi' (Russian frozen).
There were 4 grades of vodka -
1) 'prostoe vino' (plain wine)
2) 'vino dobroe' (good wine)
3) 'vino boyarskoe'(vysshii sort' (noblemans' wine, high grade)
4) 'vino dvoinoe' (osoboi 'kreposti') (double wine, extra strong)
(The first written record of the use of the word 'vodka' in the
Russian language was 8 June 1751).