Improved Process for the Manufacture of Beer.
Year: 1894

page_text: Date of Application, 20th Feb., 1894-Accepted, 28th Apr., 1894
COMPLETE SPECIFICATION.
Improved Process for the Manufacture of Beer.
I, JOHN COLT PENNINGTON, of Paterson, County of Passaic, State of New
Jersey, United States of America, 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 :-
This invention relates to processes of making beers.
The object is to produce a beer free from spores, germs, ferments, or microbes
productive of extra or spurious fermentation deleterious to its keeping and injurious
to health.
With this object in view, the invention consists in the process of sterilizing wort,
by heating and then cooling the same, allowing any residual spores to germinate,
and then further heating and cooling it, the whole under exclusion of extraneous
spores and germs, furthermore, in producing a suitable wort, then sterilizing this
wort by alternate heating and cooling, after mashing, and then sowing the
sterilized wort with pure yeast, the entire procedure being conducted with
exclusion of extraneous spores and germs; finally in the process of making beer,
which, consists first, in heating the wort two or more times in closed vessels, after
mashing at intervals of from six to twelve hours, to about the boiling point,
cooling it between each heating, thoroughly sterilize it, and then sowing it with
pure yeast, all under exclusion of extraneous spores and germs.
As an illustration of how this process may be carried into effect, the following
will serve as an example, where a pure yeast is to be made ;
I make a mash in the ordinary manner with malt alone, or with malt with any
suitable grain. The wort is placed in a closed vessel containing a suitable quantity
of hops, cand, if desired, other well-known flavouring matter. The vessel used is
of a strength sufficient to withstand considerable pressure. The wort is heated to
about the boiling point. It is then transferred without exposure to outside air, to
a vessel, closed against access of spores or germs from without, and left a suitable
time to allow any spores to germinate, say for from six to twelve hours. It is
then again heated to about the boiling point to destroy any existing germs, and is
then passed, without exposure, as before, through a cooling apparatus into
fermenting tuns also closed against access of any spores or germs. Should this
second heating, in any exceptional case, not prove sufficient, the operation of
heating and cooling, with careful exclusion of spores and germs, may be
repeated.
The fermenting tun is provided with a closed top or cover; but, in order that
carbonic acid gas may, under desired pressure, escape, a pipe provided with a
safety valve is placed in the top of the tun, the pipe being preferably packed with
cotton or substance having a similar germ-excluding function. It is possible that,
at any stage, during the heating of the liquid, extraneous spores or germs, that is
to say, spores and germs from the outside air might be, so to speak, negatively,
excluded, by the repellent action of the vapors or steam coming off and without closely
covering the liquid; but it is especially important, during the cooling of the
liquid for the germination of any residual spores, that outside or extraneous air
should be positively excluded.
The point is to prevent any access of any fresh spores or germs at any stage of
the operation by whatever means this may be effected; and the invention is
broadly in sterilizing wort and making pure beer by repeated heating and cooling
of the wort while any access of outside spores or germs is prevented in any
manner, and sowing the wort with a small quantity of pure yeast with exclusion of
outside spores or germs.

page_text: A desirable procedure is as follows;
A suitable quantity of sterilized wort is placed in a vessel having a contracted
mouth, the mouth being packed, at its lower end, with cotton or other suitable
substance. A small quantity of pure yeast is added and the whole is then ready
for fermentation. When ready, the entire contents of the vessel are transferred
into the sterilized wort within a suitable tun by any means which will protect the
said contents from contact with the outer air and undesirable spores or germs.
The object of heating the wort a number of times with intermediate cooling is
thoroughly to sterilize it, that is to say, each heating kills germs which have
developed but may not kill undeveloped spores, while the intermediate cooling
allows any residual spores to germinate, the germinated spores being then killed by
subsequent heating. The heat must be sufficiently high in degree, say about the
boiling point, and be sufficiently long continued to kill the germinated spores,
while the intermediate cooling must be of sufficient length, say from six to twelve
hours, to permit the undeveloped spores to germinate without there being time
enough for the growth or formation of new spores; and it is important that,
during the whole procedure, no extraneous spores or germs shall get into the
mixture.
I
It is well-known, that ordinary beer is a mixture containing numerous ferments;
among which are some capable of producing acids, and many other undesirable
products, and also, that the air contains germs of a variety of ferments, bacteria,
etc., whose office it is to purify and return to its elements all organic matter.
have found that the wort can be thoroughly sterilized by heating it twice or
oftener at intervals of from six to twelve hours, because the germs are not killed
by a single boiling heat, while they are killed by that heat after germination.
It will be seen, that by my procedure, a beer for direct consumption or for
distillation is produced, which having been freed from all microbes, germs, or
ferments but the pure specific yeast desired, is one which can have no extra or
spurious fermentation, presenting matter injurious to health and causing its
deterioration; and, as a matter of fact, the beer thus produced will keep
indefinitely, under any conditions of warmth, light, etc., if placed in proper vessels
with exclusion of extraneous ferments.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The procedure substantially as hereinbefore set forth.
2. As a step in making beer, the process of completely sterilizing the wort by
heating it, then cooling it, allowing any residual spores to germinate, and then
"further heating and cooling it, the whole under careful exclusion of extraneous
spores and germs, substantially as set forth.
3. The new process of making beer, which consists in producing a suitable wort,
then thoroughly sterilizing this wort by alternate heating and cooling, after
mashing, as above described, and then sowing the sterilized wort with pure yeast,
the entire procedure being conducted with exclusion of extraneous spores or
germs, substantially as set forth.
4. The process of making beer, which consists in heating the wort two or more
times to about the boiling point, at intervals of from six to twelve hours, cooling it
between each heating under exclusion of extraneous spores and germs, and then
sowing it with pure yeast under seclusion of other germ-matter, substantially as
set forth.
Dated this 20th day of February 1894.