Improvements in the Process of and Apparatus for Mashing and Brewing.
Year: 1897

page_text: Date of Application, 2nd Mar., 1897-Accepted, 22nd May, 1897
COMPLETE SPECIFICATION.
Improvements in the Process of and Apparatus for Mashing
and Brewing.
We, LADISLAUS PROCHÁZKA, of Turnau, in the province of Bohemia, in the
Austrian Empire, Brewer, and Doctor EMIL FRISCHAUER, of 6, Wipplinger Strasse,
Vienna I, in the Austrian Empire, Barrister, 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 :-
Our invention relates to improvements in the process of mashing and brewing
described in the specification of a former patent granted to one of us No. 17,246
of 1896 which process comprises the following operations, videlicet :-
1st. Separation of the mashed mixture of malt grist and hot water, by being allowed
to rest for a considerable time, into solid matters, which settle down, and clear extract
of malt, rich in diastase, which is drained from the mash tun by means of a siphon ;
2nd. Boiling of the solid sediment or grain mash in order to transform its starch
into paste;
3rd. Remixing the clear extract with the grain mash and mashing the mixture,
whereby the starch paste is saccharified or sweetened;
4th. Boiling the mixture for rendering the diastase ineffective ;
5th. Filtering the wort through the husks or returns ;
6th. Hopping the wort.
Now, the object of our present invention is the production in less time, of beer of
quite as good a quality and quite as little liable to subsequently become muddy.
According to the said invention, the mash prepared at a temperature of from
50° to 70° C. and containing from 4 to 4.5 hectolitres of water per 100 kilogrammes
of malt is not allowed to rest in order to separate the grain mash from the clear
extract, but the separation is effected by straining. The grain mash is boiled in order
that the starch it contains may be transformed into paste, and during the boiling
operation air heated to 125° C. is injected into the grain mash in order to convert a
part of the albuminous components of the malt into soluble amides and peptones.
Afterwards the clear extract of malt, containing the greater part of the diastase
having its saccharifying power unaltered, is again added to the grain mash having its
starch transformed into paste, whereby this latter is saccharified. Finally the whole
mash is subjected to coction accompanied by injection of hot air, whereby the diastase
is killed and consequently prevented from acting, during the clearing or filtration of
the wort through the husks, on the starch remains of which still exist in the returns.
The arrangement of apparatus or the brewing plant serving for carrying out the
described process is characterized by a communication pipe and cut-off valve interposed
between the vessel wherein the mash is prepared (mash tun) and a rotary strainer of
special construction, the interior of which, where the grain mash accumulates, is
connected with the boiling pan by a pipe, in which a pump is interposed.
In order to enable our invention to be fully understood we will describe the same
with reference to the accompanying drawing, in which :-
Figure 1 is a sectional elevation (on line X-X, Figure 2) of a brewing plant
suitable for carrying out our improved process; and,
Figure 2 is a plan of the said brewing plant.
Through the preliminary mashing apparatus or mixer a of any suitable con-
struction, the malt grist, wetted with water, falls into the mash tun b, where it is

page_text: mixed, at a temperature of from 50° to 70° C., with water in the proportion of from
4 to 45 hectolitres to 100 kilogrammes of malt. The mixture having been worked
by the mashing machine during about one hour, the whole contents of the mash
tun are allowed to flow through the valve carranged below the bottom of the said
tun b, into the rotary strainer d, described in the Specification of Letters Patent
No. 17,246 of 1896, designed to separate the clear extract of malt, which contains
nearly all the diastase in a perfect state, from the thick mash comprising the husks
and the yet unaltered starch. The mash flows out from the mash tun through
the pipe, which is connected to the hollow shaft of a conical sieve-drum
enclosed in the top portion of the rectangular strainer box d having an inclined
bottom. The mash egresses through slots in the hollow shaft, which revolves slowly,
and the solution of maltose and dextrine passes through the wire fabric sides of the
drum into an inclined gutter arranged beneath the drum. A pipe extending
downward from the lower end of the gutter discharges the extract of malt into
the strainer receptacle d upon the inclined bottom of which the starch granules which
are eventually carried along settle down.
The solid matters retained by the wire fabric sides of the revolving strainer-drum g
are pushed forward, by helical sheet metal ribs secured to the inner surface of
the drum g, into the cylindrical portion g', of the said drum, which has solid sides.
Thence the grain mash drops through slots g², formed in the sides of the cylindrical
portion of the drum, into a hopper g³ discharging the mash into a tank 9. In
this tank the mash is diluted with water as it arrives, and is immediately
pumped, by means of the hand pump h through the pipe into the boiling pan k.
The clear extract of malt, the solid particles of which have settled on the
inclined bottom of the strainer casing d is allowed to flow through the cock and pipe l
into the hop strainer m. As soon as the mash tun is emptied, the clear extract
is returned into the same, by means of the centrifugal pump n, through the pipe o,
three way cock 1, pipes o¹ and three way cock and pipe st. As has been
stated above, this clear extract contains nearly the whole diastase in a perfect state
of efficiency.
The sediment collecting on the inclined bottom of the casing d is discharged
⚫ through the lower cock t into the tank 94, and with the grain mash therein contained
it is pumped into the boiling pan k.
We have already explained that the object of the treatment of the grain mash is
on the one hand, to convert part of the albuminoids into soluble compounds
(amides and peptones), and on the other hand, to transform into paste the whole
of the starch contained in the husks or returns. For these purposes. the grain mash
is first heated to about 60° C., and, afterwards, air heated to 125° C. is injected
into the mass finally the grain mash is kept boiling during from 20 to 25 minutes.
The injection of heated air is effected by means of a finely perforated pipe arranged
within the boiling pan.k, and communicating, through heating pipes, located within
the furnace flues, with an air pump.
The grain mash treated in this way is then allowed to flow through the pipe u
and cock u into the lower bac v, whence the pump n raises it through the pipe w,
cock P, pipes o¹ and りっ cock and pipe s¹ into the mash tun . This re-uniting
ef the boiled grain mash with the clear extract of malt rich in diastase, which is
contained in the mash tun, has for object to enable the diastase to saccharify or to
sweeten the starch brought into the state of paste by the boiling operation. By the
energetic mixing of the mass by means of the mashing machine, the saccharification
of the starch is quickened and completed.
It is still necessary to kill the diastase in order to prevent it from acting, during
the clearing of the wort, that is to say, from filtering through the husks, onto the
granules of starch still existing among the latter, as such an action would result in
the wort becoming muddy. For this purpose the whole mash is passed into the
boiling pan k, that is to say, it is first allowed to flow into the lower bac v through
the pipe y and the valve belonging thereto, and afterwards raised through the pipe w,
cock p, pipe o', pump n, pipe q, cock and pipe into the brewing pan k. The mash

page_text: is there heated to boiling point and has hot air injected into it anew. The mash tub
being, in English brewing plants, at the same time the clearing tun, the boiled mash
is allowed to flow through the cock u and pipe u into the lower bac v, whence it is
raised by the hereinbefore described pipes, cocks and puinp into the mash tub b. The
clearing or filtering through the malt husks is effected in the usual way, and the
clear wort is allowed to pass through the pipe z into the hop-sifter m, where it is
boiled with the hops. During the boiling with the hops another injection of hot air
takes place, and to admit of this, a finely perforated pipe is arranged within the
hop-sifter m. This last injection of air completes the oxidation of the albuminoids,
and the beer consequently is no longer liable to become muddy under the action of
the gluten.
Our improved process will allow a brewer to attain a yield from 1-8 to 2.5 %
bigher than the so called theoretical yield, whilst hitherto the highest yield attained
has been from 2 to 8% lower than the latter.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. The herein described process of mashing and brewing characterized by the
following operations :-
(a) Separation, by straining, of nearly the whole of the clear extract of malt
from the returns after having brought the mash to a temperature of
from 50° to 70° C.;
(b) Boiling the grain mash, diluted with water, in order to convert the whole
starch into paste ;
(c) Re-uniting the grain mash having its starch converted into paste with the
extract rich in diastase, in order to have the paste saccharified by the latter,
(d) Boiling the whole mash in order to render the diastase inefficacious before
the clearing of the wort or its filtration through the husks.
2. In the process claimed in the preceding claiming clause injecting air heated
to 125° C. into the grain mash and complete mash while being boiled and also into
the clear wort whilst being hopped, for the purpose of transforming a part of the
albuminoids into soluble amides and peptones.
3. The herein described brewing plant for carrying out the process claimed in the
first claiming clause such plant being characterized by a mash strainer (d), which has
its straining chamber (9) connected with the mash tun, its chamber (9) where the
solid bodies collect connected by the suction and pressure pipes (1) of a pump (h)
with the boiling pan (k), and its chamber where the clear extract is received
connected to the hop-strainer.
Ton 1 M 1907
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.