IMPROVEMENTS IN REFINING STARCH SUGAR
Year: 1881

page_text: LETTERS PATENT to Peter Jensen, of 33, Chancery Lane, in the County of
Middlesex, for an Invention of "IMPROVEMENTS IN REFINING STARCH
SUGAR." A communication from abroad by Professor Doctor Franz Soxhlet,
of Munich, Bavaria, Germany.
PROVISIONAL SPECIFICATION left by the said Peter Jensen at the Office
of the Commissioners of Patents on the 13th September 1881.
PETER JENSEN, of 33, Chancery Lane, in the County of Middlesex. " IMPROVE-
MENTS IN REFINING STARCH SUGAR." (A communication from abroad by Professor
Doctor Franz Soxhlet, of Munich, Bavaria, Germany.)
The improvements refer to the refining of starch sugar (dextrose hydrate Co
H₁ 0, x H, O₁), and in the production of the same with crystalline struction,
which Invention is fully set forth in the following Specification:-
12
:-
Starch sugar (glucose) as hitherto prepared, besides containing a larger amount
of water than is necessary for water of crystallization (viz., 9-09 per cent.) contains
in every 100 parts of weight from 20 to 30 parts of unfermentable and uncrystal-
lizable substances of a gummy nature. The separation of these substances, which,
in the form of a syrup, are enclosed in the hard crystalline sugar particles, and the
preparation of a pure starch sugar (glucose) constitutes the object of the present
Invention.
The Invention consists, first, in dissolving out the substances mentioned with the
aid of ethyl or methyl alcohol; and secondly, in crystallizing grape sugar by
making a concentrated syrup and allowing it to solidify at a temperature above
30 deg. C. (86 deg. F.)
The solid mass of grape sugar is melted in a water bath or steam bath, and the
resulting syrup is mixed with 70 per cent.-80 per cent. by weight of alcohol, 80
per cent. by volume Tralles or pure undiluted wood spirit. This syrup mass is next
mixed with pulverized grape sugar, and in a place not too cool allowed to solidify.

page_text: Solidification takes place in about 8 days, during which time the whole mass
should be frequently stirred. The above process of course can be used with syrup
not yet rendered viscid for the production of the solid sugar; or the syrup can be
allowed to solidify so far as to be able to knead, and then can be intimately mixed
with 70 per cent.-80 per cent. by weight of alcohol or wood spirit, by means of
suitable machinery. Or, finally, solid starch sugar (glucose) can be pulverized and
mixed with the above mentioned liquid in the proportion indicated.
The amount of water in the mixture of syrup and alcohol must be such that
there will be no separation afterwards at common temperature. For a strong
evaporated sugar syrup a more dilute spirit is used, and for a weak syrup a more
concentrated spirit. Anhydrous wood spirit may also be employed. The liquified
mass thus produced in one of the ways described is pressed by means of a powerful
filter press, hydraulic press, or centrifugal machine. If the filter press is used a
further addition of sugar is recommended; but if the centrifugal press, on the
contrary, a further addition of the spirit. All the operations are carried on, as far
as possible, in closed vessels, in order to prevent loss of the spirit by evaporation.
The pressing also should be as powerful as possible, so that the pressed mass be dry
and powder-like, and not of a gummy consistency. The alcohol or wood spirit is
separated from the pressed cakes or the mass from the centrifugal machine by
distilling it off in vacuum before or after the said cakes are mixed with water.
The alcohol is collected in a cooled condenser. The sugar free from spirit is mixed
with water, sufficient to allow of its complete decolorization by means of animal
charcoal. After complete decolorization by the animal charcoal the syrup is
evaporated in a vacuum at a temperature not above 60 deg. C. (140 deg. F.)
For the preparation of a perfectly dry starch sugar with a chalky or porcelain-
like fracture, without a distinct crystalline form, the syrup is evaporated to a
specific gravity of 1.33-1.35 (36 deg.-39 deg. Baume at 60 deg.-65 deg. C.
(140 deg. 149 deg. F.) If the starch sugar (glucose) allowed to solidify in
moulds with smooth faces, loaf sugar with a smooth shining exterior surface is
obtained.
The formation of transparent hard starch sugar (glucose) with a distinct crys-
talline structure, in which form the starch sugar (glucose) has heretofore never
been made either in small or large quantity is based on the following hitherto
unknown fact-Starch sugar (glucose) at ordinary temperature solidifies in
opaque, wart-like, microscopic, tablet-formed crystals; but at a temperature above
-30-deg-C-(80-deg-F),-in-very-concentrated solution, it crystallizes_in_trans-
parent, column-formed crystals, easily visible to the naked eye. A solution of
starch sugar (glucose) containing only small quantities of foreign substances is
concentrated until the syrup shows at a temperature of 90 deg. C. (194 deg. F.)
a specific gravity of 137-1·48 (about 40 deg.-40 deg. Baume), best about
1.40-1.42. If during the evaporation, or when it is interrupted, the syrup
becomes cloudy there is enough of crystals present to bring about crystalline
solidification, but if the syrup remains clear, then a portion heated to 80 deg.—
90 deg. C. (176 deg.-194 deg. F.) must be vigorously mixed and stirred until it
becomes cloudy, and this must be mixed with the rest of the syrup. The syrup is
then filled into the moulds.
In order to make the viscid syrup flow better it is preferable to heat it to
80 deg. 90 deg. C. (170-194 F.) before letting it flow into the moulds. The
crystallization takes place most rapidly when the mass is cooled to a temperature
of 35 deg 50 deg. C. (95 deg.-122 deg. F.), and kept at this temperature (best
on a water bath) as constantly as possible till complete solidification.
The temperature at which the mass is to be kept depends on the concentration
of the sugar solution and its purity as well as on the more or less granular character
of the product it is desired to obtain.
For a less pure sugar solution a lower temperature of 35 deg.-40 deg. C.
195 dea-101 dec 1. for a
MARA MIMA

page_text: (104 deg. 122 deg. F.) is employed.
days.
The moulds must then be turned over in order to allow the small portion of the
remaining syrup to solidify. The sugar forms are withdrawn from the moulds
while still in a moist condition, and are allowed to dry at ordinary temperature
in a dry place. The syrup containing alcohol is preserved, and the alcohol is
recovered by distillation, best in vacuum with a cooled condenser, while the sugar
after decolorization may be used as starch sugar (glucose) syrup, or for the pre-
paration of sugar confectionery, or if it be crystallizable, for the above mentioned
process, or it may be reheated with sulphuric acid for solid starch sugar
(glucose).
Solidification takes place in two or three

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Peter Jensen in the Great Seal Patent Office on the 11th March
1882.
PETER JENSEN, of 33, Chancery Lane, in the County of Middlesex. "IMPROVE-
MENTS IN REFINING STARCH SUGAR." (A communication from abroad by Professor
Doctor Franz Soxhlet, of Munich, Bavaria, Germany.)
The improvements refer to the refining of starch sugar (dextrose hydrate
CHOH, O₁), and in the production of the same with crystalline structure,
which Invention is fully set forth in the following Specification:-
Starch sugar (glucose) as hitherto prepared, besides containing a large amount
of water than is necessary for water of crystallization, (viz. 909 per cent.),
contains in every 100 parts of weight from 20 to 30 parts of unfermentable and
uncrystallizable substances of a gummy nature. The separation of these substances,
which, in the form of a syrup, are enclosed in the hard crystalline sugar particles,
and the preparation of a pure starch sugar (glucose), constitutes the object of the
present Invention.
The Invention consists, first, in dissolving out the substances mentioned, with the
aid of ethyl or methyl alcohol; and, secondly, in crystallizing grape sugar, by
making a concentrated syrup and allowing it to soldify at a temperature above 30
degrees C. (86 degrees F.)
The solid mass of grape sugar is melted in a water bath or steam bath, and the
resulting syrup is mixed with 70 per cent.-80 per cent by weight of alcohol, 80
per cent. by volume, Tralles or pure undiluted wood spirit. This syrup mass is
next mixed with pulverized grape sugar, and in a place not to cool, allowed to
soldify. Solidification takes places in about 8 days, during which time the whole
mass should be frequently stirred. The above process of course can be used with
syrup not yet rendered viscid for the production of the solid sugar; or the syrup
can be allowed to soldify so far as to be able to knead, and then can be intimately
mixed with 70 per cent. -80 per cent. by weight of alcohol or wood spirit, by
means of suitable machinery. Or finally, solid starch sugar (glucose) can be
pulverized, and mixed with the above mentioned liquid in the proportions indicated.
The amount of water in the mixture of syrup and alcohol, must be such that
there will be no separation afterwards at common temperature. For a strong
evaporated-sugar-syrup,-a-more-dilute spirit is used, and for a weak syrup a more
concentrated spirit. Anhydrous wood spirit may also be employed.
The liquified mass thus produced in one of the ways described, is pressed by
means of a powerful filter press, hydraulic press, or centrifugal machine. If the
filter press is used, a further addition of sugar is recommended, but if the
centrifugal machine on the contrary, a further addition of the spirit. All the
operations are carried on, as far as possible in closed vessels, in order to prevent
loss of the spirit by evaporation. The pressing also should be as powerful as
possible, so that the pressed mass be dry and powder-like, and not of a gummy
consistency. The alcohol or wood spirit is separated from the pressed cakes or the
mass from the centrifugal machine, by distilling it off in vacuum, before or after
the said cakes are mixed with water. The alcohol is collected in a cool condenser.
The sugar free from spirit, is mixed with water sufficient to allow of its complete
decolorization by means of animal charcoal. After complete decolorization by the
animal charcoal, the syrup is evaporated in a vacuum at a temperature not above
60 degrees C. (140 degrees F.)
For the preparation of a perfectly dry starch sugar, with a chalky or porcelain-
like fracture, without a distinct crystalline form; the syrup is evaporated to a
specific gravity of 1.33-1-35 (36 degrees-30 degrees Baume at 60 degrees-
65 degrees C. (140 degrees-149 degrees F.). If the starch sugar (glucose) is
allowed to solidify in moulds with smooth faces, loaf sugar with a smooth shining
exterior surface is obtained.

page_text: The formation of transparent hard starch sugar (glucose) with a distinct
crystalline structure in which form the starch sugar (glucose) has heretofore never
been made either in small or large quantity, is based on the following hitherto
unknown fact:-Starch sugar (glucose) at ordinary temperature solidifies in opaque,
wart-like, microscopic, tablet-formed crystals, but at a temperature above 30 degrees
C. (86 degrees F.) in very concentrated solution it crystallizes in transparent
column-formed crystals easily visible to the naked eye. A solution of starch sugar
(glucose) containing only small quantities of foreign substances is concentrated
until the syrup shows at a temperature of 90 degrees C. (194 degrees F.) a specific
gravity of 137-148 (about 40 degrees-46 degrees Baume) best about 1·40-1.42.
If during the evaporation, or when it is interrupted, the syrup becomes cloudy
there is enough of crystals present to bring about crystalline solidification, but if
the syrup remains clear, then a portion heated to 80 degrees-90 degrees C.
(176 degrees-194 degrees F.) must be vigorously mixed and stirred until it becomes
cloudy, and this must be mixed with the rest of the syrup; the syrup is then filled
into the moulds. In order to make the viscid syrup flow better, it is preferable
to heat it to 80 degrees-90 degrees C. (176-194 F.) before letting it flow into
the moulds. The crystallization takes place most rapidly when the mass is cooled
to a temperature of 35 degrees-50 degrees C. (95 degrees-122 degrees F.) and
kept at this temperature (best on a water bath) as constantly as possible till com-
plete solidification. The temperature at which the mass is to be kept depends on
the concentration of the sugar solution and its purity, as well as on the more or less
granular character of the product it is desired to obtain. For a less pure sugar
solution a lower temperature of 35 degrees-40 degrees C. (95 degrees-104 degrees
F.), for a more pure a temperature of, 40 degrees-50 degrees C. (104 degrees―
122 degrees F.) is employed. Solidification takes place in two or three days; the
moulds must then be turned over in order to allow the small portion of the
remaining syrup to solidify.
The sugar forms are withdrawn from the moulds while still in a moist condition,
and are allowed to dry at ordinary temperature in a dry place. The syrup con-
taining alcohol is preserved, and the alcohol is recovered by distillation, best in
vacuum with a cooled condenser, while the sugar after decolorization may be used
as starch sugar (glucose) syrup, or for the preparation of sugar confectionery, or if
it be crystallizable for the above mentioned process, or it may be reheated with
sulphuric acid for solid starch sugar (glucose).
And having thus described and ascertained the nature of this Invention, and
the manner of carrying the same into effect, as communicated to me, I declare
that I claim,—
First. The method of purifying starch sugar (glucose) by dissolving the foreign
substances, which for the most part are unfermentable, and enclosing the solid
sugar particles with the aid of ethyl or methyl alcohol, and then separating the
thin liquid syrup from the solidified glucose by means of presses, centrifugal
machines, or other suitable appliances, substantially as described.
Second. The method of preparing solid transparent starch sugar (glucose) or
dextrose hydrate (C. H₁ O + H, O) with a distinct crystalline structure by making
a concentrated starch sugar (glucose), and allowing the same to solidify at a
temperature above 30 degrees C. (86 degrees F.) substantially as described.
In witness whereof, I, the said Peter Jensen, have hereunto set my hand
and seal, this Eleventh day of March, in the year of our Lord One thousand
eight hundred and eighty two.