Watertown republican. [volume] (Watertown, Wis.) 1860-1906, 1890-06-04
THE ARTICLE OF GLUCOSE.
What 1t Is, and the Process of It's Manu-
facture.

There is often THIS In a name-1 IL DE
unfamiliar, and especially if it pertain
to thing or substance that we do not
understand the composition or nature
of-we are apt to regard it with suspi-
cion, at least, and to distrust, and per-
haps even denounce it. This has been
the case in the popular estimation of
the article of glucose, though more
intimate acquaintance with it's nature,
and it's value as an article OF food, Will
make the public more tolerant OF 1t.
Glucose is saccharine product, derived
artificially from starch. It is known
that starch, when taken into the stOm
ach, is operated on by the gastric juice,
which turns it into glucose in the pro-
cess of digestion. The production of
glucose is carried on artifcially, in a
way that it is here proposed to briefly
describe. 1t is known that in the pro-
cess of brewing, the mailing of the
grain develops maltese from the starch
ton to glucose. The latter is also said
to be produced in measure by the
same process. At any rate it is found
to answer the same purpose, and is
largely used in the brewing industry.
How is glucose produced, commercial
ly? The process of making it will be
best understood by following the corn
from which it is made from the time it
enters the factory until it runs out of
the spigot a clear, odorless liquid. The
shell-corn is first soaked for several days
in water, to soften the hull and prepare
it for the cracking process. The soft
ened corn is conveyed by elevators to
one of the highest stories of the factory
and shoveled into large hoppers, from
which it passes into mills that merely
crack the grains without reducing them
at once to a fine meal. The cracked
grain is then conducted to large tank
filled with rinsing water. The hulls of
the corn float at the top of the water,
the germs sink to the bottom, and the
portions of the grain, becoming gradual
~ reduced to flour by friction, are held
in solution in the water. By an in
genious process both the hlllls and the
germs are removed, and the flour part
now held in solution contains nothing
but starch and gluten. This liquid is
then made to flow over a series of ia
bles, representing several acres in area,
and the difference in the specific gravity
of the two substances causes the gluten
and the starch to separate without the
use of chemicals. The gluten is of
golden yellow color, and the starch snow
white. By the time the gluten has been
completely eliminated the starch as
sumes plastic form, and is collected
from the separating tables by wheelbar-
rowflls and taken TO a drving-room,
where it is prepared as the starch of
commerce, or 1t is placed in chemical
apparatus, to be converted into glucose.
The conversion is effected by submit
ting the starch TO the action of minute
percentage OF dilute sulphuric acid,
which, without becoming constituent
mart nf tho fnmnnI1nH nrnHunnc
by its presence merely a miraculous
change. This change from starch to glu-
cose is a gradual process, and has four or
five well-detined stages. On the addi-
ton of the acid the first change results
in the production of what is known to
chemists as dextrine. If at this stage
the acid is neutralized by the addition
of lime water the process is choked and
dextrine is the permanent product. If
the process is allowed to 90 on the acid,
however, works a second change, and
maltese is the result. Here, also, the
process can, if necessary, be interrupt
ed by neutralizing the acid by means of
lime water land for some processes in the
art of brewing this is sometimes done.
The third and important stage in the
chemical change wrought by the action
results In the production of glucose, and
just here is where the greatest skill of
the chemist is required. The product
must show by tests that it responds to
the chemical formula, CO, HIP, O6. By
comparing the formula with that of
starch, which is CO, H10, O5-that is, 6
parts of carbon to 10 of hydrogen and 5
of oxygen--it will be seen that the sui
phuric acid has not added to the starch,
but has taken up two parts of hydrogen,
and the only gain in the starch is one
part of oxygen.
The lime water introduced to neu-
tralize the acid forms, with it, product
called gypsum-sulphate of lime-which
can be removed from the glucose with
out leaving any appreciate trace The
fourth stage IN the chemical process re-
suits in crystalizing the liquid, and then
the product is called grape sugar. There
is fifth stage in which caramel, or
burnt sugar, could be produced were it
of any commercial value. The gypsum,
or sulphate of lime, formed by the neu-
tralizing lime water and sulphuric acid,
sinks by gravitation to the bottom of the
vessel, and the supernatant saccharine
liquid is drawn off from the top This
is almost pure chemical glucose, but it is
still subject to filtering process through
bone black, and refined in the same way
as cane sugar Is refined. The bone
black has anything but the appearance
of a purifying agent, but possesses the
peculiar property of attracting to itself
all coloring matter. The glucose, pass
ing through labyrinthine system of
filtering, is drawn off through
spigots in the lower part of the building
and is ready to be shipped away in bar
rels. To give the glucose the appear
ance of cane syrup, as we'll as to fmpart
some Of the Characteristic taste, a small
amount Of that syrup is added to suit the
fancy of buyers. To make grape sugar
the glucose is dried in rapid y-revolving
vessels, from which much of the moist
ure escapes by virtue of the centrifugal
force. Neither the glucose nor the
grape sugar is used for domestic pur-
poses, although either one is about two
thirds as sweet as the sweetest cane SUI
gar. Glucose is largely used by makers
of cheap candies; but chiefly for fer
menting purposes, and of late years has
become valuable to the brewer in MAX
ing beer and pale ales It is also large
ly used in mixtures with cane syrups
and molasses, and is esteemed by those