IMPROVEMENTS IN BREWING
Year: 1871

page_text: LETTERS PATENT to Louis Pasteur, of 45, Rue d'Ulm, Paris, Franco,
a Member of the Institute of France and of the Royal Society of
London, for the Invention of "IMPROVEMENTS IN BREWING."
Sealed the 30th January 1872, and dated the 24th August 1871.

page_text: Suppression of the necessity for storing cellars.
Greater yield and an equal or superior strength of beer.
A very clear and limpid beer with an agreeable bouquet..
The carrying on fermentation at low temperatures rendered unne-
cessary.
For these purposes the wort of beer when obtained is conducted in a
boiling state into vats or receivers of wood or metal, and cooled by a
current of water in a current of carbonic acid gas, and is then put into
a state of fermentation.
:
The warm water drawn off at the lower part of the apparatus serves at
once for a fresh operation.
Small quantities of air may be allowed to enter the apparatus during
the cooling of the wort if this air be first burnt to destroy any germs
which may be in suspension in it.
.
The beer after its first fermentation is drawn off into casks to finish
the process and to clarify, or the making of the beer may be finished in
the fermenting vats.
U
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]
1
The above process is based upon scientific data to a great extent new,
and from which it results that although the contact of air is useful in 2
the making of beer, yet it may carry along with it when badly employed
the most serious evils.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Louis Pasteur in the Great Seal Patent Office on-
the 23rd February 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LOUIS
PASTEUR, of 45, Rue d'Ulm, Paris, France, a Member of the Institute of
France and of the Royal Society of London, send greeting.
2
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of August, in the year of 8
our Lord One thousand eight hundred and seventy-one, in tlie thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Louis Pasteur, Her special license
that I, the said Louis Pasteur, my executors, administrators, and
:

page_text: -
assigns, or such others as I, the said Louis Pasteur, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter. during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
BREWING," upon the condition (amongst others) that I, the said
Louis Pasteur, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Louis Pasteur, do hereby declaré
the nature of the said Invention, and in what manner the same is to
be performed; to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
This Invention consists in conducting the process of making beer in
such a manner that the wort shall be protected during the time of.
cooling and until the completion of the fermenting process from all
germs which may be suspended in the atmosphere.
In carrying out my Invention I prefer to proceed as herein-after
described.
:
}
The wort having been prepared in the ordinary manner and when
ready for cooling is directed as boiling and as clear as possible into
cylinders or vats by preference of tin plate.
The Drawing annexed represents at A, A, the construction of cylinder
I prefer to employ. When the cylinder has been filled with boiling
wort the cover is put on; this cover is furnished with a descending rim
which enters the gutter g. The gutter is kept filled with water up to.
the overflow outlets P., and so closes the cylinder with a hydraulic joint.
After having closed the tap R', opened the tap R", and applied the tube
B, C, D, E, E, the tap R is opened for the passage of a stream of fresh
water of a temperature lower than that to which the wort is to be reduced
before putting in the ferment. The water falling through the per-
forations of the rose head fills the gutter g and passes by the overflows
to the perforated ring tube t, from which it flows down the exterior of,
the sides of the cylinder into the gutter g', and is carried off in a heated

page_text: state by the gutter M, either to be used for a fresh brewing or for other
requirements of a brewery. During this time the external air enters the
cylinder by the tubo B, C, D, E, E, made in lengths connected by
vulcanized india-rubber tubes. E, E, is a glass tube with two descending
bends in which a few drops of water are placed, and all air passing
through the pipe must necessarily pass through the water in these bends.
The advantages arising from these arrangements are the wort in the
first instance being boiling and all the parts of the cover having been
well washed with boiling water, all gorms capable of impairing beer wort
are destroyed, and the air which enters by the exterior tube E, D, C,
B,
cannot carry in with it fresh ones. By these means the wort of beer
may be kept for any required time, even during the heat of summer,
without any of the various microscopic organisms arising in it which I
have found are invariably the cause of unsoundness in beer or in the
wort from which it is produced. When the thermometer T, T, (the bulb
of which is immersed in the liquid and is protected by a perforated cap)
marks on its outer stem the desired temperature for the putting in of the
ferment, the tap R is closed, and yeast, mixed with a small quantity of
wort drawn off at L, is introduced, either through the tap R' or R".
Here arises a slight opportunity for the introduction of germs from the 2
outer air either from contact with the air ar from germs which the ferment
may contain from previous operations, but the effect is trifling and of
no practical importance if the yeast is carefully watched and protected,
as is evidenced by the fact that beer made by this new process keeps
much better than beer made from the same wort by the old process.
As soon as carbonic acid gas commences to pass off by the tube E, E,
the tap R which had previously been closed immediately after the
putting in of the yeast is opened, and the extremity B of the outer tube
is detached to give a free passage to the carbonic acid gas; as soon as
the violent fermentation has ceased the tap R¹ may be closed and the 3
end B of the pipe again attached to R", the gas then passes away at E, E.
As soon as it is judged that the attenuation of the wort is sufficient the
beer is drawn off by the tap L. Both in the case of high or of low
fermentation all the yeast falls to the bottom of the apparatus, and is
taken away after the drawing off of the beer through the man-hole K. 8
In place of the long tube D, C, B, for admitting air to the vessel A
during the cooling operation a much shorter tube may be made use of
if it be heated for a part of its length sufficiently to destroy any germs

page_text: which may be in suspension in the air which passes through it. Carbonio
acid gas may also be employed. In this case a reservoir is placed above
the fermenting apparatus, which is constantly filled with this gas arising
during the progress of the fermentations. By connecting this reservoir
with the tap R¹ or R", the gas will flow like a liquid on to the surface
of the boiling wort and maintain there an atmosphere of pure gas free
from germs. By the other tap the excess of gas may repass to the
reservoir.
For beer of high fermentation the beer should remain in the apparatus
for about twelve days before drawing off, and for fifteen or twenty days
for beer of low fermentation.
The clearing of the beer in the casks is very rapid, even when it is
drawn off thick and charged with ferment.
The apparatus is carefully cleaned after each operation with boiling
water and subsequently with cold water, brooms or brushes of hair or
grass being used.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that I claim, the making
beer substantially in the manner herein-before described.
In witness whereof, I, the said Louis Pasteur, have hereunto set
my hand and seal, this Fourteenth day of February, in the year
of our Lord One thousand eight hundred and seventy-two.
T. PASTETR