IMPROVEMENTS IN REFINING AND CRYSTALLIZING 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 AND
CRYSTALLIZING 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 AND CRYSTALLIZING STARCH SUGAR," A communication
from abroad by Professor Doctor Franz Soxhlet, of Munich, Bavaria, Germany.
These improvements refer to the refining and crystallization of anhydrous starch
sugar (dextrose anhydryde, C, H₁, 0), and the production of the same with
crystalline structure, all as hereinafter described.
6 12
The production of such anhydrous and crystallized starch sugar (Cε H₁₂O), which
hitherto has never been made, is accomplished in the following manner:-Starch
sugar (glucose) solution is concentrated in vacuum until a sample is hardly
kneadable when cool. The stiff syrup, heated not above 70 deg. C. (158 deg. F.), is
freely mixed in closed vessels with boiling hot pure wood spirit (methyl alcohol).
The quantity of the wood spirit depends upon the purity of the starch sugar
(glucose), and also upon the expected quality of the product. In case ordinary
starch sugar (glucose) is used, which contains from 20 per cent. to 30 per cent. of
substances not sugar, then take to 100 parts of the concentrated syrup 70 to 80
parts of wood spirit and allow it to crystallize in closed vessels at a temperature of
30 deg. to 40 deg. C. (86 deg. to 104 deg. F.) The crystallization is hastened by
the addition of some anhydrous crystalline starch sugar (glucose).
The granular mass can be separated by means of centrifugal power or suitable
presses, and purified further by displacing or washing with wood spirit. Granulated
porous starch sugar (glucose) with clear, perfect, visible, and glittering crystals,
having the appearance of refined cane sugar, is produced in the following
manner:
A clear and colorless starch sugar (glucose) solution, freed as much as possible
from foreign substances, is concentrated in vacuum to the above mentioned

page_text: consistence. The syrup must be perfectly clear like water, if it be only a trifle
cloudy in consequence of the formation of crystals, which sometimes happens in
consequence of a too slow or an interrupted evaporation, then such a syrup would
be unsuitable for the following operation, owing to the production of hydrated
crystals of the sugar. One mixes 100 parts by weight of the syrup heated to
about 70 deg. C. (158 deg. F.) with 10 to 25 parts by weight of boiling hot pure
methyl alcohol (wood spirit) until a thin syrup-like mass is obtained, then the
same is filled, while still hot, into conical moulds.
Afterwards the same is slowly cooled down to 30 deg.-35 deg. C. (86 deg.-
95 deg. F.), and kept at. this temperature until crystallization is complete. After
two or three days the remaining fluid is drawn off. In case the sugar is wanted
thicker and more solid, the remaining fluid is drawn off and the porous mass is
saturated once or twice with a mixture of 100 parts of thick syrup and 80 to
100 parts of wood spirit. This operation as well as the further crystallization can
be performed at common temperatures.
When the desired density is obtained the fluid portions are sucked off and
displaced with pure methyl alcohol, of which 5 per cent. of the weight of the sugar
is sufficient, then the solid mass is taken out of the moulds. The methyl alcohol is
separated from the sugar by placing the loaf in a vacuum pan with a well cooled
condenser. The methyl alcohol is first distilled off at 35 deg. C. (95 deg. F.), but
after the distillation of the larger portion the temperature is gradually raised to
50 deg. 60 deg. C. (122 deg.-140 deg. F.). If the sugar is kept for a few hours
in vacuum at a temperature of 50 deg.-60 deg. C. (122 deg.-140 deg. F.) then no
more trace of the methyl alcohol can be recognized either by taste or smell. From
the drained off portions the methyl alcohol is re-obtained by distilling in vacuum
or in the ordinary way. The total loss of the methyl alcohol is one tenth (1), 80
that the real consumption of the same for the last explained process amounts only
to 2 per cent.-2 per cent.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Peter Jensen in the Great Soal Patent Office on the 11th March
1882.
PETER JENSEN, of 33, Chancery Lane, in the County of Middlesex..
-86 IMPROVE
MENTS IN REFINING AND CRYSTALLIZING STARCH SUGAR." (A communication
from abroad by Professor Doctor Franz Soxhlet, of Munich, Bavaria, Germany.)
These improvements refer to the refining and crystallization of anhydrous starch
sugar (dextrose anhydryde C, H,, O), and the production of the same with crystalline
structure, all as hereinafter described.
The production of such anhydrous and crystallized starch sugar (C, H₁, O₂) which
hitherto has never been made is accomplished in the following manner :-Starch
sugar (glucose) solution is concentrated in vacuum until a sample is hardly knead-
able when cool. The stiff syrup heated not above 70 degrees C. (158 degrees F.)
is freely mixed in closed vessels with boiling hot pure wood spirit (methyl alcohol).
The quantity of the wood spirit depends upon the purity of the starch sugar
(glucose), and also upon the expected quality of the product. In case ordinary
starch sugar (glucose) is used, which contains from 20 per cent. to 30 per cent. of
substances not sugar, then take to 100 parts of the concentrated syrup 70 to 80
parts of wood spirit, and allow it to crystallize in closed vessels at a temperature
of 30 degrees to 40 degrees C. (86 degrees to 104 degrees F). The crystallization is
hastened by the addition of some anhydrous crystalline starch sugar (glucose).
The granular mass can be separated by means of centrifugal power or suitable
presses, and purified further by displacing or washing with wood spirit. Granu-
lated porous starch sugar (glucose) with clear, perfect, visible, and glittering crystals,
having the appearance of refined cane sugar, is produced in the following
manner :-
A clear and colorless starch sugar (glucose) solution, freed as much as possible
from foreign substances, is concentrated in vacuuin to the above mentioned con-
sistence. The syrup must be perfectly clear, like water; if it be only a trifle
cloudy in consequence of the formation of crystals, which sometimes happens in
consequence of a too slow or an interrupted- evaporation, then such a syrup would
be unsuitable for the following operation, owing to the production of hydrated
crystals of the_sugar. One mixes 100 parts by weight of the syrup heated to
about 70 degrees C. (158 degrees F.) with 10 to 25 parts by weight of boiling hot
pure methyl alcohol (wood spirit) until a thin syrup-like mass is obtained, then
the same is filled while still hot into conical moulds.
Afterwards the same is slowly colled down to 30 degrees-35 degrees C. (86
degrees 95 degrees F.), and kept at this temperature until crystallization is com-
plete. After two or three days the remaining fluid is drawn off. In case the sugar is
wanted thicker and more solid the remaining fluid is drawn off, and the porous mass
is saturated once or twice with a mixture of 100 parts of thick syrup and 80 to
100 parts of wood spirit. This operation, as well as the further crystallization,
can be performed at common temperatures. When the desired density is obtained,
the fluid portions are sucked off and displaced with pure methyl alcohol, of which
5 per cent. of the weight of the sugar is sufficient, then the solid mass is taken out
of the moulds. The methyl alcohol is separated from the sugar by placing the
loaf in a vacuum pan with a well cooled condenser. The methyl alcohol is first
distilled off at 35 degrees C. (95 degrees F.), but after the distillation of the larger
portion the temperature is gradually raised to 50 degrees-60 degrees O.
(122 degrees-140 degrees F.) If the sugar is kept for a few hours in vacuum at
a temperature of 50 degrees-60 degrees C. (122 degrees-140 degrees F.), then no

page_text: more trace of the methyl alcohol can be recognized either by taste or smell.
From the drained off portions the methyl alcohol is re-obtained by distilling in
vacuum or in the ordinary way. The total loss of the methyl alcohol is one tenth
C/10th), so that the real consumption of the same for the last explained process
amounts only to 2 per cent.-21/2 per cent.
And having thus described and ascertained the nature of this Invention, and
in what manner it is carried into effect as communicated to me, I declare that I
claim,―
The production of anhydrous crystalline starch sugar (dextrose anhydride C
H₁, O) by the crystallisation of a mixture of starch sugar (glucose) and wood
spirit at the above mentioned temperature, as set forth.
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.
THANK