ALCOHOL 
only in preparing spirituous beverages of 
somewhat higher alcoholic strength than 
could be obtained by fermentation alone. 
The first stills were very crude and sim- 
ple in design, and were incapable of pro- 
ducing distillates of great strength from 
the wine which invariably was used as 
the material for distillation. It was in- 
deed found by the early chemists that if 
the first weak distillate was subjected to 
a second and third distillation its alco- 
holic strength could be raised (though at 
the expense of a material diminution in 
its volume) to such an extent that it 
would burn, but the expensiveness of the 
product thus obtained was too great to 
allow its use for any industrial purposes. 
At present wine and other fermented 
fruit juices are distilled only for the 
production of potable spirits; and indus- 
trial aleohol is made altogether by the 
distillation of fermented saccharine solu- 
tions which are prepared either directly 
from raw materials containing sugar, such 
as molasses, or from starchy materials 
like potatoes or the cereal grains, after a 
preliminary treatment which converts 
their starch into sugar. 
Theory of Alcoholic Fermentation 
The process of alcoholic fermentation 
is established whenever yeast is allowed 
to act on sugar solutions of moderate 
strength at temperatures between 50 de- 
grees and 90 degrees Fahrenheit. Theo- 
retically the process consists of a simple 
splitting up of sugar into alcohol and 
carbonic acid gas, any given amount of 
sugar yielding proportionate and perfectly 
definite amounts of these two products of 
its decomposition. This is illustrated in 
the following example: 
The chemical composition of dextrose, 
which is the form of sugar occurring in 
most ripe fruits, is represented by the 
formula C,H,.0,, which signifies that one 
molecule or unit of the compound sub- 
stance dextrose is made up of six atoms 
or units of the element carbon, 12 of 
the element hydrogen, and six of the ele- 
ment oxygen. When fermentation takes 
place, the molecule of dextrose breaks up 
substantially as is indicated by the fol- 
lowing equation: 
C.H,.0, = 2 C,H,OH + 2 CO.. 
This signifies that after fermentation 
is over the dextrose will have disappeared 
and in its place will be found an amount 
of alcohol containing all the hydrogen, 
two-thirds of the carbon, and one-third 
of the oxygen of the sugar, and an amount 
of carbon dioxid containing one-third of 
its carbon and two-thirds of its oxygen. 
Theoretically the total weights of the al- 
cohol and carbon dioxid which are pro- 
duced in the fermentation should equal 
exactly the weight of dextrose which is 
decomposed, and 100 pounds of the sugar 
should yield 51.11 pounds of aleohol and 
48.89 pounds of carbon dioxid. 
In practice, however, the decomposition 
is never complete, nor is it ever so simple 
as is indicated by the foregoing equation. 
Only in carefully conducted laboratory 
work is it ever possible to ferment any 
sugar completely; and even then, as a re- 
sult of life processes of the yeast which 
are not yet understood by chemists or 
biologists, small and varying proportions 
of sugar escape transformation into al- 
cohol, and are converted instead into 
other substances. According to the inves: 
tigations of Pasteur, 100 pounds of dex- 
trose, instead of yielding the theoretical 
weights of alcohol and carbonie acid in- 
dicated by the equation, will produce in 
laboratory practice the following amounts 
of fermentation products: 
Pounds 
AICOHOL] oo. eee ccceeeeceeeeeeeee ceeeeeeeeserances 48.5 
Carbon dioxid 2. oo... lect eeeeneee 46.74 
OAC) =) oy 5 6 3.23 
Organic Acids oo... eee. cee eeeeeceeeeeeee 62 
MisSCeHane@Ous 20... cecececceceeseeccueeeenecees 1.23 
Total o.oeeeeeecececccceseseeceetene  cececenececeenee 100.37 
The fact that the total weight of the 
fermentation products exceeds slightly the 
weight of sugar fermented is explained 
on the ground that the formation of cer- 
tain of the by-products is accompanied by 
the absorption and fixation of slight 
amounts of water. 
In manufacturing work, such complete- 
ness of fermentation may be taken as an 
ideal toward which one is to strive. Ac- 
cording to the skill of the distiller, the 
character of his mechanical equipment, 
