Improvements in Obtaining an Extract of Malt and Hops, and in Preparing a Confection of the same.
Year: 1890

page_text: Date of Application, 24th Dec., 1890
Complete Specification Left, 24th Sept., 1991-Accepted, 24th Oct., 1891
TRUVIDIUNAL DILUIFICATION.
.
Improvements in Obtaining an Extract of Malt and Hops, and in
Preparing a Confection of the same.
I, EDWARD SONSTADT, of Church fields, Cheshunt, Herts., Fellow of the
Chemical Society, do hereby declare the nature of this invention to be as
follows:
Freshly ground malt is infused with hot water, (usually taken in similar pro-
portion to that used in making brewers' worts), for some hours, at a temperature
slowly rising to about 70° C., preferably in a closed vessel supplied with an agitator,
in which vessel air is expelled by passing in carbon dioxide gas. The hot liquor
is run or strained off, and the residue is further infused in like manner, for a
shorter period, and it may be, at a slightly higher temperature, with a fresh
portion of water. The washing may be again repeated, if desirable.
The
The liquors thus obtained are placed in a close boiler, and hops, in proportion
usually of about one-tenth of the weight of malt taken, are added. An upright
cohobating tube or column is adapted to the cover of the boiler, to which is also
adapted a tube communicating with a gasometer or vessel kept charged with
carbon dioxide gas, from which by water pressure or otherwise the gas may be
passed into the boiler. The connecting tube is supplied with a cock.
cohobating tube has a branch tube near the top, (which is closed) leading to a
small closed receiver, which receiver is connected, first, to a small Woulfe's bottle,
containing a little fresh butter, and then to a series of U tubes or other suitable
vessels, with inlet and outlet taps, charged with recently heated asbestos, pre-
ferably all cooled by ice or otherwise. The last vessel of the series is connected
to a long vertical depending tube, the end of which dips into a bottle or vessel
containing either liquid or solid extract, or confection, wherein any aroma not
condensed in the preceding vessels is caught and absorbed.
The described arrangements having been made, heat is applied to the boiler,
either by a steam-jacket or otherwise, and the contents are kept slowly boiling at
such a rate, that a very little steani may pass into and condense in, the first
receiver. The liquid thus condensed is rich in aroma. By keeping up a very
slow current of carbon dioxide, the aroma not thus condensed in water is carried
on through the other vessels of the series, where it is successively absorbed by the
butter, by the asbestos, and lastly in the vessel containing fluid or solid extract, or
the confection, to be hereafter described. After a few hours' regulated boiling,
more or less according to circumstances, the liquid is run out from the boiler, as
for instance through a cock with strainer; or the drawn liquor may be cleared by
subsequent settling and filtering.
But although the boiling may be conducted in the manner stated, I prefer to
use an arrangement which I have already, as to its main features, described in
specifications of inventions relating to making extracts of tea and coffee. The
closed vessel in which the malt infusion and hops are placed, (the "digester ") is
connected near the top to a "supplementary boiler" standing on a higher level,
by a cock through which hot or boiling water may be admitted at will. This
supplementary boiler" is only used as a reservoir of hot water. The "digester"
is provided with a tube (the "syphon tube") passing through the cover and
continued to very near the conical or tapering bottom of the digester, and pro-
vided at the end with a rose or perforated cap. At a little distance from the
bottom, a grid or perforated plate is attached to the tube, serving as a false-
bottom. Above the cover, the "syphon tube" is continued, with the necessary
€

page_text: bends or curves, so as to enter the cover of a closed boiler placed near the digester,
and preferably on a lower level. Then, when the "digester has been charged as
described with hops and malt infusion, and connected to the apparatus for con-
densing aroma-water and aroma, water placed in the connected boiler is heated by
direct flame (or by superheated steam if desired, passing into a surrounding
jacket) and is brought to a boil, the steam passes through the "syphon tube
into the digester, and boils the contents. When the boiling in the digester has
been thus maintained for a certain time, the flame or source of heat is withdrawn
or lowered, the cock in the tube leading to the aroma-condensing apparatus is
closed; and the cock in the tube leading from the carbon dioxide reservoir is
opened. The condensation of steam in the boiler, then occasions suction, and the
clear liquor is drawn through the syphon tube into the boiler. The cock leading
to the supplementary boiler may now be opened to admit hot water to the digester;
heat is again applied to the boiler, and steam is passed in as before, the cock
leading to the aroma-condensing apparatus being re-opened. By repeating this
process two or three times, or more, the hops in the digester may be as effectually
washed as may be desired, and the boiling may be maintained as long as may be
necessary to secure the valuable aroma. When this stage of the process is
completed, the infusion of the malt and hops is in the boiler, whence it is with-
drawn by a conveniently placed cock, to be taken to the evaporator.
It is convenient to adapt an open water-jacket to part of the digester, to allow
of better control of the rate of boiling by the injected steam within the digester,
so that too much steam may not pass off with the aroma. Usually I prefer not
to condense more than about one per cent. of the total quantity of water taken, as
aroma-water.
The evaporator, or vessel which the infusion of malt and hops obtained as
described is concentrated, is preferably hemispherical in form, with a flange around
the edge, depressed outwards, and provided with a rim, and outlet tube. A conical
hood or cover, provided with a water-jacket, rests upon the flange close to the rim,
so that the flange forms a trough or channel into which the water condensed from
the steam produced during evaporation, collects, and flows through the outlet tube
into a receptacle. The evaporator may be heated by direct flame; but is preferably
heated by a steam-jacket. From near the top of the hood, a tube passes to lead
off any uncondensed steam to any suitable cooled vessel. I prefer to provide the
hood of the evaporator with an inlet tube to admit carbon dioxide gas, which may
be passed slowly in during the evaporation, to prevent access of air to the surface
of the liquid. The water condensed from the steam given off during concentration,
carries some aroma, and is used instead of ordinary water, in the boiler, for the
next digestion. When the liquor in the evaporator has acquired a suitable strength
for forming a liquid extract, it is run off by an outlet provided for that purpose,
into suitable bottles, to be aromatised as hereafter described. Sometimes I
evaporate nearly to dryness, redissolve, and filter. But if it is desired to produce
a solid extract, or a confection, the concentration is carried so far as may be, so
that the liquor may be fluid enough when hot, to be fit for running off.
The thus highly concentrated liquor is run into a "mixer," a stout cylindrical
vessel, with closely fitting cover or top, through a stuffing-box in which a shaft
passes carrying arms, which serve to agitate the contents. A valved tube in the
cover admits exit of steam, which may be taken to a condenser. The mixer may
be heated, carefully, by direct heat, or by a jacket for superheated steam. When
the extract is so far concentrated that a sample taken out becomes hard on cooling
(or the concentration may be carried further), sugar is added in proportion to the
product required. For a paste, some of the sugar added (preferably white lump
sugar) is moistened with the aroma-water obtained as previously described, with
addition sometimes of a little of the aromatised butter; if a confection is required,
à larger proportion of sugar, and much more aromatised butter, are added. In
either case, after the addition the cover is secured on, and the properly heated mass
is worked up thoroughly by use of the agitator. The product, while yet hot, may

page_text: be removed, and moulded when required, and put into bottles or vessels, which are
then properly closed.
To aromatise the liquid extract, the aromatised asbestos is collected from the
tubes in which it absorbed aroma, and is placed in a retort or flask with a portion
of water, preferably some of the water collected during concentration of the
infusion. A tube is led from the retort dipping into the liquid extract, and
a small proportion of water, (which carries with it practically all the aroma)
is distilled into the liquid. The latter is then (or it may be before this
operation) placed to receive excess aroma from another working of the digester
and boilers, in connection with the condensing apparatus for aroma already
described. The liquid is then bottled up, securely corked, and heated to about
100° C. for a certain time, to sterilise it, when, if it be effectually protected from
in-leakage of air, it will keep in good condition, preserving the aroma. But I
prefer to use the process of stoppering and sterilising described in the Specification
of an invention, for which I have applied for provisional protection, No. 20,411,
A.D. 1890. The solid extract, or the confection, may be further aromatised, by
passing the excess aroma obtained during a working through a vessel charged with
such extract or confection; in the manner described as applied to the liquid
extract. The spent asbestos is drained, dried, and heated, but not necessarily to a
red heat, for re-use.
In some cases, I distil off a little water as described from a mixture of aroma-
tised asbestos and water, not directly into the liquid extract, but into a cooled
condenser, to obtain a strong aroma-water, which may be used as directed for the
aroma-water obtained in working the digester.
I prefer to use aluminium as the material for the digester, boiler, and mixer. It
may also be used for the evaporator, though for this, copper, silver-plated internally,
is very suitable. But the digester, boiler, and mixer, may be made of copper,
nickel- or silver-plated. Gun-metal, nickel- or silver-plated within, may also be
used for the mixer; but aluminium is preferable. The syphon tube should be of
aluminium, or silver, or of a suitable metal or alloy thickly plated with silver. As
only water is admitted to the supplementary boiler, this may be of any metal from
which hot water will not take up any injurious matter.
Dated this 2nd day of December 1800
COMPLETE SPECIFICATION.
Improvements in Obtaining an Extract of Malt and Hops, and in
Preparing a Confection of the same.
I, EDWARD SONSTADT, of Churchfields, Cheshunt, Herts., Fellow of the
Chemical Society, 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 :-
Freshly ground malt is infused for some hours with hot water, in similar pro-
portion to that used in making brewers' worts. The infusion is preferably effected
in a closed steam-jacketed vessel through which a current of carbon dioxide gas
is passed, and the temperature is allowed to slowly rise to about 70° C. When
the liquor is run or strained off, the residue is further infused for a shorter time
with more water, and the temperature may rise slightly higher than before, to
obtain a further portion of the infusion. If desirable, the washing may be again
repeated.
The liquor thus obtained is placed in a close boiler or digester with, say, about
one part of hops to ten parts of the malt taken for infusion. But the proportion
may be varied to suit requirements. Fresh and unsulphured hops are preferred.
An upright cohobating tube is adapted to the cover of the digester, to which is
also adapted a tube with cock, through which a current of carbon dioxide gas is
passed into the digester. The cohobating tube is connected near the top to a

page_text: branch tube leading to a small cooled receiver, in which any steam reaching so far
is condensed, with much of the hop aroma. The receiver is connected to a
Woulfe's bottle or other suitable vessel, containing fresh butter, which is again
connected to a series of vessels charged with recently heated asbestos, and there
may be a final vessel charged with the finished confection, or with the liquid
extract, to absorb any remaining aroma. These aroma-absorbing vessels are
preferably cooled by ice, and may be of any convenient form, and suitable material.
The carbon dioxide gas may be introduced by way of the top of the cohobating
tube, or by an independent tube entering the boiler. The gas has exit through the
series of aroma-collecting vessels. It is convenient that the tube connecting to
the carbon-dioxide gas supply, and the tubes connecting the aroma-collecting
vessels should be supplied with taps. The butter-containing condenser is dispensed
with, when a liquid extract only is required. Other suitable oils or fats may be
substituted for butter; and slag-wool or glass-wool, or the like, for asbestos, as
aroma-absorbing substances, though not advantageously.
The boiler or digester, when duly charged and connected, may be heated, by a
steam-jacket or otherwise, so as to keep the contents slowly boiling, the steam
condensing in the upright cohobating tube, and returning to the boiler, only a little
steam being allowed to pass into the first receiver, where it is condensed with much
aroma. The boiling is continued for some hours, or as long as necessary for
collection of the best of the aroma. The liquor may be discharged from the
digester, when ready, by a cock with strainer; or the unstrained liquor may be
cleared by subsidence and filtration...
If desired, the digester charged with hops and malt infusion, and connected as
described, may be boiled by steam delivered under a false-bottom in the digester,
by a tube passing through the cover to a closed vessel or boiler, preferably on a
lower level. In this case it is best to provide the digester with an open water-
jacket, so that the rising of steam into the aroma-condensing vessels may be
checked when necessary. It is also convenient to connect the digester by a tube
close under the cover to a hot-water reservoir on a higher level, so that by turning
a cock, any required quantity of hot or boiling water may be run in at pleasure.
Carbon dioxide gas is passed in as before described. The tube connecting the
boiler to the digester, serves also as a suction or syphon tube, for emptying the
latter of liquid, when desired, this being effected by simply withdrawing the source
of heat from the boiler, when the steam-vacuum produced causes the liquor to flow
from the digester into the boiler, whence it may be withdrawn-by- a-cock. The
syphon tube has a perforated cap at its end in the digester, to serve as a strainer.
More hot water may be run into the digester, so as to wash the contents, the steam
being got up again (liquid enough being left in the boiler for the purpose), and
the liquor sucked back as before. The washings may be repeated as often as
desired, simultaneously with continued collection of aroma during the passage
of steam. The arrangements are similar to those that I have described in the
Specification to No. 3172, A.D. 1889, relating to the preparation of an extract
of coffee.
The malt and hops infusion, obtained as described, is taken hot to a concentrator
or evaporating dish, which is preferably similar to that described in the before-
named Specification. A hemispherical form of evaporator is convenient, with a
flange around the edge, depressed outwards, and provided with a rim, and outlet
tube. A conical hood or cover, provided with a cooling water-jacket, rests upon
the flange close to the rim, so that the flange forms a trough or channel into which
the water condensed from the steam produced during evaporation, collects, and
flows through the outlet tube into a receptacle. The evaporator may be heated
by a steam-jacket; or a jacket charged with a material of high boiling point, as
ozokerit for instance, heated directly by a flame, may be used. A tube may be
provided near the top of the hood, to take off uncondensed steam, but with proper
cooling of the hood by the water jacket, it is unnecessary. The hood should be
provided with an inlet tube for carbon dioxide gas, a current of which is kept

page_text: flowing during the progress of the evaporation, and may have exit by the outlet
tube which conducts away the water of condensation.
When a liquid extract is required, the liquor in the evaporator, when sufficiently
concentrated, is run into a receptacle, preferably some form of bottle or flask, with
not too wide a neck, and is cooled. The aroma-charged asbestos taken from the
aroma-condensing vessels, is put into a flask or retort, and is well wetted or
covered with water, preferably water of condensation obtained during the process
of concentration. A tube is led from the flask or retort, dipping into the liquid
extract, the vessel containing which is cooled. Heat is applied to the retort, by
a sand-bath, or ozokerit-bath, for instance, until a small proportion of the water
in the retort is distilled over into the extract. The aroma passes with the
steam which condenses in the extract. A very little boiling suffices to convey
practically all the aroma into the extract. The asbestos may then be drained,
dried, and heated, not necessarily to redness, to fit it for re-use. The aroma-
water collected in the small condenser connected to the digester in the process
of obtaining the malt and hop infusion, is then added, and the liquid extract,
after some agitation, is put into bottles, which are firmly corked. The corks
are secured by string or otherwise, and the bottles are then slowly heated in
a water or steam-bath up to the boiling point of water, which temperature is
preferably maintained for an hour or more. They are then allowed to cool
slowly, but while yet warın, the fastenings are removed, the corks are cut off
flush with the top of the bottles, and the corked ends are dipped in any suitable
melted matter which on cooling will solidify and form an air-tight covering.
I have found melted ozokerit to answer the purpose very well, but do not
confine myself to the use of this. The bottles charged with extract thus treated
and sterilised may be stored for any length of time without the contents under-
going change.
When a solid extract is to be made, the concentration is carried as far as may
be in the evaporator, consistently with leaving the liquid fit for pouring while hot.
The thus highly concentrated liquor is run into a mixer, similar to that described
in the before-cited Specification. The mixer is a stout cylindrical vessel, with
closely fitting cover, through a stuffing-box in which a shaft passes carrying arms,
which serve to agitate the contents. A valved tube in the cover permits exit of
steam, which may be condensed if desired. The mixer may be heated by direct
When the extract is so far
heat, or may be jacketed for superheated steam.
concentrated that a sample becomes hard on cooling, sugar, some of which is
moistened with aroma-water, is added. For a paste, more moistened sugar is used;
for a solid confection, much dry sugar with some moistened sugar and the aroma-
tised butter, are used. In either case, after the addition, the cover is secured on,
and the properly heated mass is worked up thoroughly by use of the agitator. The
product, while yet hot, may be removed, moulded when desired, and stored in
closed bottles or vessels. The " aroma-water" referred to is obtained by distilling
the aromatised asbestos with water, and collecting the distillate in a well-cooled
condenser, care being taken that the least possible proportion of water is distilled
over that will carry the aroma. The aroma-water collected in the small condenser
connected to the digester, in the process of obtaining the malt and hop infusion,
may also be used.
The digester, boiler, and mixer, are preferably made of aluminium. If made of
other metal, they should be silver-plated internally. The syphon tube should be
of silver or aluminium.
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 I
claim is:
(1). The digestion of malt infusion with hops in an atmosphere of carbon
dioxide, simultaneously with collection of the aroma evolved, substantially in the

page_text: (2). The concentration of the malt and hops infusion in an apparatus through
which a current of carbon dioxide is passed, substantially as described.
(3). The aromatisation of the concentrated malt and hops infusion to form a fluid
extract, and its sterilisation, and storage, substantially as described.
(4). The preparation of a paste or solid malt and hops extract, including its
aromatisation by aromatised sugar and butter, substantially as described.
Dated this 24th day of September 1891.
E. SONSTADT.