Process for the Preparation of Hop-extract.
Year: 1890

page_text: Date of Application, 24th Dec., 1890
Complete Specification Left, 17th Oct., 1891-Accepted, 21st Nov., 1891
PROVISIONAL SPECIFICATION.
Process for the Preparation of Hop-extract.
I, Dr. AUGUST FOELSING, Manufacturer, of Düsseldorf, Germany, do hereby
declare the nature of my invention to be as follows:-
I employ a battery of diffusion apparatuses, fill the latter with hops and a suitable
quantity of water, and then commence the extraction. at a pressure of 1½ atmo-
spheres and a temperature of about 60 degrees C. This pressure may be produced
by pumps, and the temperature by a steam pipe coil placed in the diffusion
apparatus, or steam may be admitted directly into the extracting apparatus for
lixiviating the hop.
To render the extraction complete and to obtain in an unoxidised condition the
resinous matter (so called hop-resin) which is sparingly soluble in water, and also
the volatile hop-oil, which requires more than 600 parts of water for its dissolution,
I add to the water about 24 per cent. of a gum, preferably gum tragacanth.
According to Bungener, the bitter principle of hops is the resinous product of the
oxidation of the "lupulin-acid" which always exists in the plant along with the
said acid; and is easily formed at the expense of the latter.
The addition of gum promotes this formation, but arrests a further oxidation,
which would be injurious. According to requirement, the water is changed three
or four times during the extraction, and the liquor obtained by the above process is
boiled down in vacuo to about 25° Baumé.
Dated this 24th day of December 1890.
FAIRFAX & WETTER,
433, Strand, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Process for the Preparation of Hop-extract.
I, Dr. AUGUST FOELSING, Manufacturer, of Düsseldorf, Germany, do hereby
declare the nature of my. invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
I employ a battery of diffusion apparatus, fill the latter with hops and a suitable
quantity of water, and then commence the extraction at a pressure of 11 atmo---
spheres and a temperature of about.60-degrees-C: -This pressure may be produced
by pumps, and the temperature by a steam pipe coil placed in the diffusion
apparatus, or steam may be admitted directly into the extracting apparatus for
lixiviating the hop.
To render the extraction complete and to obtain in an unoxidized condition the
resinous matter (so called hop-resin) which is sparingly soluble in water, and also
the volatile hop-oil, which requires more than 600 parts of water for its dissolution,
I add to the water about 24 per cent. of gum, preferably gum tragacanth. According
to Bungener, the bitter principle of hops is the resinous product of the oxidation
of the "lupulin-acid" which always exists in the plant along with the said acid, and
is easily formed at the expense of the latter.
The addition of gum promotes this formation, but arrests a further oxidation,
which would be injurious. According to requirement, the water is changed threc
or four times during the extraction, and the liquor obtained by the above process is
boiled down in vacuo to about 25° Baumé.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what 1
claim is: .
The manufacture of hop-extract, which consists in treating the hops with water
containing about 2½ per cent. of gum, at a pressure of about 1 atmospheres and a
temperature of about 60° Centigrade, and subsequently concentrating in vacuo the
extract thus obtained, substantially as described.
Dated this 12th day of October 1891.
FAIRFAX & WETTER,
433, Strand, London, Agents.