An Improved Process and Apparatus for the Production of Dry, Extract of Coffee.
Year: 1889

page_text: Date of Application, 10th Dec., 1889
Complete Specification Left, 10th Sept., 1890-Accepted, 10th Dec., 1890
An Improved Process and Apparatus for the Production of Dry,
Extract of Coffee.
I, HENRI BAROTTE, of 23, Boulevard de Strasbourg, Paris, in the Republic of
France, Chemist, do hereby declare the nature of this invention to be as follows:-
My invention relates to a process and apparatus for the production of dry extract
of coffee.
My process consists essentially in extracting all the aromatic properties of ground
coffee by dry distillation in vacuum by means of a special apparatus hereinafter
described.
This apparatus consists of a jacketed cylinder heated by superheated steam, and
communicating with a copper sphere serving to cool and condense the aromatic
vapours of the coffee. The internal cylinder is mounted upon a hollow shaft which is
rotated by means of a pulley. The cooling sphere is provided with a tube having a
movable stuffing box to which an india-rubber tube is adjusted for the purpose of
placing the internal cylinder in communication with a pump for producing the
vacuum.
The coffee already roasted and finely ground is introduced into the internal rotating,
cylinder, and the cooling sphere is adjusted thereto and placed in communication
with the pneumatic pump by means of the movable stuffing-box. A vacuum being
produced in the cylinder, the latter is rotated by placing the driving band over the
pulley; this rotary motion is continued during the whole of the operation.
By means of a cock the superheated steam is admitted through two hollow trunnions.
to the jacket, the said trunnions allowing the cylinder to oscillate. After a certain
time has elapsed the pressure-gauge will indicate a reduction of the pressure which
must be re-established by means of the pump; the vacuum is thus renewed whenever
the pressure-gauge falls below 65%. When the thermometer exceeds 160° Centigrade.
the internal pressure is allowed to increase and the pressure-gange quickly falls:
When the pressure-gauge registers no more than 10% of vacuum the steam cock is
closed; the temperature will then be about 200° Centigrade.
The apparatus is then left for about five to ten minutes during which time the
pressure-gauge will fall to 0"/m and the thermometer will rise to 210°. As soon as this
temperature is reached (and it must not be exceeded) the cooling must be commenced
by injecting cold water in small quantities through a cock into the jacket. When the
apparatus well cooled the rotation is discontinued, air is introduced into the
apparatus and the distilled product is collected in the sphere.
This product is a yellow or reddish liquid which must be filtered and immediately
added to extract coffee which has been prepared by a previous operation aș
hereinafter explained.
The coffee deprived of its aromatic properties and remaining in the apparatus is.
taken out and placed in well heated distilled water. The resulting infusion is evaporated
in vacuum in the usual manner. The thick extract obtained with or without the
addition of sugar is completely dried by means of heat and in vacuum:.in both cases.
the pulverized product is added as already described to a corresponding proportion
of filtered liquid product. The moist mixture is dried in vacuum either under the
action of a very slow heat or by means of chemical absorbents, such as sulphuric acid
or chloride of calcium.
This mixture is a product which I shall call "Express Café:" It is a powder which
is of a greyish colour, if sugar be added thereto, and black if pure.
The coffee. deprived of its aromatic properties, and remaining in the cylinder may

page_text: have added thereto a suitable proportion of chicory or other similar substance such as
'dried dates before making the infusion; the extract obtained and aromatized as
herein before described is specially suitable for making what is generally known as
café au lait..
i
By dissolving the extract in water coffee can be instantly made.
1A 1
G. F. REDFERN & Go; T
4, South Street, Finsbury, London, Agents for the Applicant.
'An Improved Process and Apparatus for the Production of Dry
Extract of Coffee.
I, HENRI BAROTTE, of Place Daumesnil, Paris, France Chemist, 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:--
My process consists essentially in extracting all the aromatic properties of ground
coffee by dry distillation in vacuuin by means of the apparatus hereinafter
described.
In the annexed drawings, Fig. 1 is a sectional end elevation and Fig. 2 a side
elevation of my apparatus for carrying out my invention.
This apparatus consists of a jacketed cylinder A heated by superheated steam, and
communicating with a copper sphere serving to cool and condense the aromaticvapours
of the coffee. The internal cylinder C is mounted upon a hollow, shaft D which is
rotated by means of a pulley E. The cooling sphere B is provided with, a tube F
having a movable stuffing-box to which an india-rubber tube is adjusted for the
purpose of placing the internal cylinder C in communication with a pump for producing
the vacuum.
The coffee already roasted and finely ground is introduced into the internal
rotating cylinder C, and the cooling sphere is adjusted thereto and placed in com-
imunication with the pneumatic pump by means of the movable stuffing-box. A
vacuum being produced in the cylinder, the latter is rotated by placing the driving
band over the pulley E: this rotary motion is continued during the whole of the
operation.
By means of a cock G the superheated steam is admitted, through two hollow
trunnions H H to the jacket, the said trunnions allowing the cylinder A to oscillate.
After a certain time has elapsed the vacuum-gauge I will indicate a reduction of the
vacuum which must be re-established by means of the pump; the vacuum is. thus.
renewed whenever the depression or vacuum falls below 65% of mercury. When the
thermometer J exceeds 160° Centrigrade the internal pressure is allowed to increase and
the vacuum-gauge quickly falls. When the vacuum-gauge régisters no more than
10m of vacuum the steam cock is closed; the temperature will then be about
200° Centigrade.
The apparatus is then left for about five to ten minutes during which time the vacuum-
gauge will fall to 0 /m and the thermometer will rise to 210°. As soon as this tempera-
ture is reached (and it must not be exceeded) the cooling must be commenced by
injecting cold water in small quantities through the cock K into the jacket A. When
the apparatus is well cooled the rotation is discontinued, air is introduced into the
apparatus and the distilled product is collected in the sphere.
This product is a yellow or reddish liquid which must be filtered and immediately
added to extract of coffee which has been prepared by a previous operation as herein
after explained.
The coffee deprived of its aromatic properties and remaining in the apparatus is
taken out and placed in well heated distilled water. The resulting infusion is
evaporated in vacuum in the usual manner. The thick extract obtained with or without
the addition of sugar is completely dried by means of heat and in vacuum; in both

page_text: cases the pulverized product is added, as already described, to a corresponding pro-
bortion of filtered liquid product. The moist mixture is dried in vacuum either under
the action of a very slow heat or by means of chemical absorbents, such as sulphuric
acid or chloride of calcium.
.
This mixture is a product which I call Express Café." It is a powder which is
of a greyish colour, if sugar he added thereto, and black if pure.
The coffee, deprived of its aromatic properties, and remaining in the cylinder may
have added thereto a suitable proportion of chicory or other suitable substance such
as dried dates before making the infusion; the extract obtained and aromatized as
hereinbefore described is especially suitable for making what is generally known as
café au lait."
the action of a very slow heat or by means of chemical absorbents, such as sulphuric
acid or chloride of calcium.
.
This mixture is a product which I call Express Café." It is a powder which is
of a greyish colour, if sugar be added thereto, and black if pure.
The coffee, deprived of its aromatic properties, and remaining in the cylinder may
have added thereto a suitable proportion of chicory or other suitable substance such
as dried dates before making the infusion; the extract obtained and aromatized as
hereinbefore described is especially suitable for making what is generally known as
café au lait."
By dissolving the extract in water coffee can be instantly made.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed 1 declare that what I
claim is
1st. Extracting all the aromatic properties or principles, or elements, of ground
coffee by dry distillation in vacuum by means of the apparatus combined in sub-
stantially the manner described.
2nd. For extracting all the aromatic properties of ground coffee by dry distillation
in vacuum, an apparatus consisting of a jacketed cylinder heated by superheated
steam and communicating with a cooling sphere in which condense the aromatic
vapours of coffee.
3rd. The apparatus consisting of a cylinder mounted upon a hollow shaft and a
cooling sphere provided with a tube having a movable stuffing-box for the purpose
of placing the cylinder in communication with vacuum-pump.
4th. Extracting the aromatic properties of ground coffee introduced into the internal
rotating cylinder above described, by producing and maintaining vacuum permanent
and uniform in the cylinder, rotating the latter and admitting the superheated steam
through two hollow trunnions to the jacket, the said trunnions allowing the cylinder
to oscillate.
5th. In an apparatus combined and operating as before described, heating ground
coffee and maintaining vacuum until the temperature reaches 160° Centigrade, then
reducing vacuum to 10% and closing steam cock, after what the vacuum falls to 0.
and the temperature rises from 200 to 210° and, at last, cooling by injecting cold
water into the jacket, discontinuing the rotation, introducing air into the apparatus,
and collecting distilled product in the sphere.
6th. Filtering and immediately adding the liquid product obtained, as before
described, to pulverized extract of coffee obtained by infusion resulting from coffee
deprived of its aromatic properties and remaining in the apparatus, this infusion
having been evaporated in vacuum, the thick extract so obtained with or without
the addition of sugar being completely dried by means of heat and in
vacuum.
•