Improvements in the Manufacture of Crystallized Grape-sugar.
Year: 1885

page_text: Improvements in the Manufacture of Crystallized Grape-sugar.
We ALFRED SEYBERLICH; Sugar Manufacturer of Riga, and ALEXANDER
TRAMPEDACH, of Mitau, Courland, both in the Empire of Russia, do hereby
declare the nature of our invention for "IMPROVEMENTS IN THE MANUFACTURE
OF CRYSTALLIZED GRAPE-SUGAR " to be as follows:-
The
Our invention relates to the manufacture of crystallized grape-sugar.
present process differs from those heretofore in use in that the employment of
alcohol, bone-charcoal, or permanganate of potash for the purification clearing and
discolouration of the liquid grape-sugar is rendered unnecessary.
The said invention exhibits several new features, of which the following may be
specially mentioned viz:-
1st The saccharification of the starch by the exclusive use of diluted nitric
acid; and
2nd The alkalization of the sugar liquor prior to the inspissation in a vacuum,
by means of carbonate of soda.
In the conversion of starch into sugar by means of diluted sulphuric acid, a small
quantity of nitric acid has heretofore been used in order to accelerate the sacchari-
fication. The use of pure nitric acid has, however, not been possible in the processes
hitherto adopted for the reason that the product obtained invariably contains
considerable quantities of syrup together with the soluble substances contained in
the syrup, and consequently the salts produced in the neutralization when nitric
acid is used, impart to the product such a strong saline taste as to render the sugar
unfit for consumption. The use of nitric acid is therefore ouly admissible when
the syrup is completely separated. This separation is attained by the second part
of the process.
Hitherto only such a small quantity of an alkali has been added to the sugar
juices that it was scarcely sufficient for the neutralization of the acids. We have
found, however, that the sugar separates by crystallization much more completely
from alkaline solutions than from only neutral or perhaps partially acid solutions.
The sugar separates from the latter only in fine needles which unite and enclose a
large quantity of syrup which cannot be removed by centrifugal action.
This defect is removed by the improved process. Trials have shewn that the
starch or grape sugar separates from alkaline solutions, not in fine needles, but in
plain, strong crystals of a distinctly individual character, so that under centrifugal
action the syrup is very easily and completely separated from the pure sugar.
This process consequently enables the use of pure nitric acid for the sacchari-
fication of the starch.

page_text: The manufacture of grape-sugar according to this invention is as follows that is
to say. Air-dried starch is mixed with water to form a milk and into the latter is
slowly introduced boiling diluted nitric acid in the proportion of from two to ten
kilogramms of nitric acid to 1000 kilogramms of starch."
The proportion of the starch to the entire quantity of the water can be
from to .
The mixture is next boiled in wooden, stone or other suitable vessels, upon which
"the nitric acid does not exert an action injurious to the product. These vessels can
if desired be provided with cooling appliances. The conversion into sugar is very
complete, and in the progress of the saccharification alcohol may be caused to react
upon the substance. The boiling must be continued until 10 drops of the sugar
liquor do not cause dimness in 20 cubic centimeters of alcohol of 90º.
The acid of the thin juice is then neutralized by chalk, lime-stone, dolomite, or
similarly acting substances and is next brought by means of a caustic alkali or the
carbonate of an alkali, or an alkaline earth in excess, to a distinctly alkaline
reaction. The thin juice, the reaction of which is thoroughly alkaline, is inspissated
in a vacuum to from 33 to 36° Baumé (spec wght: 1·2943 to 1·3311) and is then
left to crystallize.
From this distinctly alkaline sugar liquor the sugar separates in single crystals
which do not contain any portions of syrup worth mentioning, so that the latter
can be perfectly and easily separated by centrifugal action. The new process differs
in this respect essentially from those heretofore used.
To the liquors of sugar have hitherto been added only slight quantities of an
alkali which were scarcely sufficient for effecting the neutralization. From such
partially acid liquors, the sugar separates by crystallization in small needles, which
combine together, thus forming a close net-work, enclosing a considerable quantity
of syrup, which cannot be removed by centrifugal force and materially injures the
quality of the sugar by its bad taste.
The syrup is separated from the crystal mass by centrifugal force or in any other
suitable manner, and the remaining grape-sugar crystals which are destitute of
water furnish, after cleansing, a commercial product containing from 96 to 98 per
cent of sugar,
The syrup flowing off is sometimes evaporated and left to crystallize. The syrup
which does not crystallize is mixed with sulphuric acid so that the nitrate of lime
contained in the said syrup is converted into sulphate of lime and free nitric acid.
This syrup is freed from the sulphate of lime by pressure, and as it contains the
greatest portion of the nitric acid originally employed, it is used in the next
operation.
In every boiling operation it is necessary to add sufficient nitric acid to make up
for waste.
This process of neutralizing the sugar liquors can also be advantageously
employed in the known processes of saccharification by means of sulphuric acid
under pressure. But then peroxide of hydrogen or some other suitable oxidizing
medium must be added to the liquor, which is alkaline, in order to oxidize the
glutinous substances arising from the albuminous portions of the starch in the
boiling with sulphuric acid, as the said substances would otherwise render
the crystallization of the sugar difficult or prevent part of the latter altogether
from crystallizing.
As already stated, according to this process a product is obtained, which consists
of single crystals containing from 96 to 98 per cent of sugar.
HASELTINE, LAKE & Co.,
For the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements in the Manufacture of Crystallized Grape-sugar.
We, ALFRED SEYBERLICH, Sugar Manufacturer, of Riga, and ALEXANDER
TRAMPEDACH, of Mitau, Courland, both in the Empire of Russia, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
The
Our invention relates to the manufacture of crystallized grape-sugar.
present process differs from those heretofore in use in that the employment of
alcohol, bone-charcoal, or permanganate of potash for the purification, clearing,
and discolouration of the liquid grape-sugar is rendered unnecessary.
The said invention, however, exhibits several new features, of which the following
may be specially mentioned viz :-
1st The saccharification of the starch by the exclusive or predominant use of
diluted nitric acid; and
2nd The alkalization of the sugar-liquor prior to the inspissation in a vacuum
by means of carbonate of soda.
In the conversion of starch into sugar by means of diluted sulphuric acid a
small quantity of nitric acid has heretofore been used in order to accelerate the
saccharification. The use of pure nitric acid has, however, not been possible in the
processes hitherto adopted, for the reason that the product obtained in variably
contains considerable quantities of syrup together with the soluable substances
contained in the syrup, and consequently the salts produced in the neutralization
when nitric acid is used, impart to the product such a strong saline taste as to
render the sugar unfit for consumption. The use of nitric acid is therefore only
admissible when the syrup is completely separated. This separation is attained by
the second part of the process.
Hitherto only such a small quantity of an alkali has been added to the sugar
juices that it was scarcely sufficient for the neutralization of the acids. We have
found, however, that the sugar separates by crystallization much more completely
from alkaline solutions than from only neutral, or perhaps partially acid, solutions.
The sugar separates from the latter only in fine needles which unite and enclose a
large quantity of syrup which cannot be removed by centrifugal action.
This defect is removed by the improved process. Trials have shown that the
starch or grape-sugar separates from alkaline solutions, not in fine needles, but in
plain, strong crystals of a distinctly individual character, so that under centrifugal
action the syrup is very easily and completely separated from the pure sugar.
This process consequently permits the use of pure nitric acid for the sacchari-
fication of the starch.
The manufacture of grape-sugar according to this invention is as follows, that is
to say. Air-dried starch is mixed with water to form a milk and into the latter

page_text: is slowly introduced boiling diluted nitric acid in the proportion of from two to ten
kilogramms of nitric acid to 1000 kilogramms of starch. The diluted nitric acid
can also be mixed with a small portion of sulphuric acid or other acid.
The proportion of the starch to the entire quantity of the water can bo
from to .
The mixture is next boiled in wooden, stone, or other suitable vessels upon which
the nitric acid does not exert an action injurious to the product. These vessels can,
if desired, be provided with cooling appliances. The progress of the saccharification
may be recognized by means of the well-known alcohol reaction applied to samples
taken from the mixture. The boiling must be continued until 10 drops of the
sugar liquor do not dim 20 cubic centimetres of alcohol of 96°.
The acid of the thin juice is then neutralized by chalk, lime-stone, dolomite, or
similarly acting substances and is next brought by means of a caustic alkali or
the carbonate of an alkali, or an alkaline earth in excess, to a distinctly alkaline
reaction. The thin juice, the reaction of which is thoroughly alkaline, is inspissated
in a vacuum to from 33° to 36° Baumé (spec: wght, 1.2943 to 1.3311) and is then
left to crystallize.
From this distinctly alkaline sugar liquor the sugar separates in single crystals
which do not contain any portions of syrup worth mentioning, so that the latter
can be perfectly and easily separated by centrifugal action. The new process
differs in this respect essentially from those heretofore used, in which only slight
quantities of alkali were added to the sugar liquor, which quantities were scarcely
sufficient for effecting the neutralization. From such partially acid liquors, the
sugar separates by crystallization in small needles, which combine together, thus
forming a close net-work, enclosing a considerable quantity of syrup, which cannot
be removed by centrifugal action and which materially injures the quality of the
sugar by its objectionable taste.
The syrup is separated from the crystal mass by centrifugal force or in any
other suitable manner, and the remaining grape-sugar crystals which are destitute
of water furnish after cleansing a commercial product containing from 96 to 98 per
cent of sugar.
The syrup flowing off is sometimes evaporated and left to crystallize. The
syrup which does not crystallize is mixed with sulphuric acid so that the nitrate
of lime contained in the said syrup is converted into sulphate of lime and free
nitric acid. This syrup is freed from the sulphate of lime by pressure, and as it
contains the greatest portion of the nitric acid originally employed, it is used in the
next operation.
In every boiling operation it is necessary to add sufficient nitric acid to make up
for waste..
This process of neutralizing the sugar liquors can also be advantageously
employed in the known processes of saccharification by means of sulphuric acid
under pressure. But then peroxide of hydrogen or some other suitable oxidizing
medium must be added to the liquor, which is alkaline, in order to oxidize the
glutinous substances arising from the albuminous portions of the starch in the
boiling of sulphuric acid, as the said substances would otherwise render the crystal-
lization of the sugar difficult or prevent part of the latter altogether from
crystallizing.
As already stated, according to this process a product is obtained which consists
of single crystals containing from 96 to 98 per cent of sugar.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is
First. In the manufacture of grape-sugar, the saccharification of the starch by
the exclusive or predominent use of diluted nitric acid, and the treatment of the

page_text: remaining syrup, containing nitrate of lime, with sulphuric acid or other suitable
acid for recovering the nitric acid.
Second. In the extraction of grape-sugar from starch-sugar liquors produced
by means of nitric acid or sulphuric acid or mixtures of these acids, the treatment
of the said liquors with a caustic alkali, or the carbonate of an alkali, or an alkaline
earth in excess, for obtaining a distinctly alkaline sugar-liquor from which the
augar separates in perfect single crystals, the syrup remaining in the same being
easily removed by centrifugal action.