AN IMPROVED TREAT- MENT OF HOPS FOR THE PRESERVATION THEREOF
Year: 1879

page_text: LETTERS PATENT to Louis Naumann and Carl Pohl, both of Plauen, near
Dresden, in the German Empire, for the Invention of "AN IMPROVED TREAT-
MENT OF HOPS FOR THE PRESERVATION THEREOF.”
Sealed the 20th August 1879, and dated the 19th June 1879.
:
PROVISIONAL SPECIFICATION left by the said Louis Naumann and Carl'
Pohl at the Office of the Commissioners of Patents on the 19th June 1879.
LOUIS NAUMANN and CARL POHL, both of Plauen, near Dresden, in the German
Empiro. "AN IMPROVED TREATMENT OF HOPS FOR THE PRESERVATION THEREOF.”
It has long been desired to find an effectual mode of preserving hops in order
principally to have a constant supply of uniform quality throughout the year, and
to equalize the supplies for years of bad harvest. Various methods have been pro-
posed for their preservation, all of which however are more or less imperfect or
objectionable. Thus in the compression of hops in bales or in cases lined with
metal the former do not protect the hops sufficiently against the action of the air or
moisture, while the latter burst frequently, not being sufficiently strong to with-
stand the pressure. The sulphurizing process protects the hops only for a short
time, while the extract of hops on the other hand has not met with general applica
tion, firstly, because in its manufacturo the hops are not so economically utilized
as when fresh hops are used; and, secondly, because the proper proportion between
the aroma and the bitter principle cannot readily be maintained therein. The
compression of the hops in metal boxes which are afterwards closed hermetically
was a considerable improvement, as an effectual preservation was thereby attained
for a certain length of time, but it has been proved that hops so treated are also
liable to the same deterioration as compressed hops in bales if stored in the ordinary
hop store houses for a considerable length of time.
Our present Invention has for its object a method of preserving the hops which
besides effectually maintaining the good quality of the hops shall, firstly, be capable
of practical application in every brewery and at a very moderate cost; and, secondly,
shall be such that the hops so treated shall be applicable in the same manner as
ordinary hops in the usual brewing process.
Our Invention consists simply in treating the hops with alcohol, for which
purpose they are sprinkled therewith and well mixed by stirring or otherwise, after

page_text: which they are compressed in any convenient manner into receptacles of suitable
construction, which are thou closed. The sprinkling and mixing might be effected
by special apparatus, but it is not necessary to perform this operation with very
great care, as in the prossing the hops will be acted upon by the alcohol throughout
with sufficient uniformity. For enclosing the hops casks such as are readily
available in breweries are employed by preference.
The mechanical operations are of so simple a character that they do not require
further description.
The very peculiar relation in which the alcohol stands to the aroma, the bitter
principle and the resinous matter produces. the most favourable results in the
browing process carried out with hops treated according to our Invention. Such
preserved hops are boiled in precisely the same manner as fresh onos, during which
process the alcohol naturally evaporates at once without leaving the slightest
detrimental effect upon the beer produced; on the contrary the aroma is improved
thereby. We have furthermore proved that a saving of 10 per cent. is effected by
the use of our preserved hops as compared with the use of fresh hops, which is
sufficient to cover all expenses attendant on the preserving process; also the fining
of the beer produced is effected perfectly and quicker than with ordinary hops.
The above facts have been thoroughly proved by us by long continued
experiments.
No deterioration of such preserved hops takes place through any heating that
may occur during storage, as the alcohol effectually provents this, and consequently
tho hops may be stored in any localities which are used for storing ordinary
hops.
As before stated every brewery can carry out the treatment of hops according to
our Invention, as a treatment with sulphur such as is necessary with every other
existing process is not required. No definite proportions of the alcohol can be
given, as this is entirely dependent on the quality of the hops to be used, and can
only be determined by experiment.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Louis Naumann and Carl Pohl in the Great Seal Patent Office on
the 8th October 1879.
.
LOUIS NAUMANN and CARL POHL, both of Plauen, near Dresden, in the German
Empire. "AN IMPROVED TREATMENT OF HOPS FOR THE PRESERVATION THEREOF."
- It has long been desired to find an effectual mode of preserving hops in order
principally to have a constant supply of uniform quality throughout the year, and
to equalize the supplies for years of bad harvest; various methods have been pro-
posed for their preservation, all of which however are more or less imperfect or
objectionable. Thus in the compression of hops in bales or in cases lined with metal
the former do not protect the hops sufficiently against the action of the air or
moisture, while the latter burst frequently, not being sufficiently strong to with-
stand the pressure. The sulphurizing process protects the hops only for a short
time, while the extract of hops on the other hand has not met with general applica-
tion, firstly, because in its manufacture the hops are not so economically utilised as
when fresh hops are used; and, secondly, because the proper proportion between
the aroma and the bitter principle cannot readily be maintained therein. The
compression of the hops in unmetal boxes which are afterwards closed hermetically
was a considerable improvement, as an effectual preservation was thereby attained
for a certain length of time, but it has been proved that hops so treated are also
liable to the same deterioration as compressed hops in bales if stored in the ordinary
hop store houses for a considerable length of time.
Our present Invention has for its object a method of preserving the hops, which
besides effectually maintaining the good quality of the hops shall, firstly, be capable
of practical application in every brewery and at a very moderate cost; and, secondly,
shall be such that the hops so treated shall be applicable in the same manner as
ordinary hops in the usual brewing process.
Our Invention consists simply in treating the hops with alcohol, for which
purpose they are sprinkled therewith and well mixed by stirring or otherwise,
after which they are compressed in any convenient manner into receptacles of
suitable construction, which are then closed. The sprinkling and mixing might be
effected by special apparatus, but it is not necessary to perform this operation with
very great care, as in the pressing the hops will be acted upon by the alcohol
throughout with sufficient uniformity.
For enclosing the hops casks such as are readily available in breweries are
employed by preference. The mechanical operations are of so simple a nature that
they do not require further description.
The very peculiar relation in which the alcohol stands to the aroma, the bitter
principle, and the resinous matter produces the most favourable results in the
brewing process carried out with hops treated according to our Invention. Such
preserved hops are boiled in precisely the same manner as fresh ones, during which
process the alcohol naturally evaporates at once without having the slightest detri-
mental effect upon the beer produced; on the contrary the aroma is improved
thereby. We have furthermore proved that a saving of 10 per cent. is effected by
the use of our preserved hops as compared with the use of fresh hops, which is
sufficient to cover all expenses attendant on the preserving process; also the tining
of the beer produced is effected perfectly and quicker than with the ordinary
hops.
The above facts have been thoroughly proved by us by long continued
experiments.
No deterioration of such preserved hops takes place through any heating that
may occur during storage as the alcohol effectually prevents this, and consequently
the hops may be stored in any localities which are used for storing ordinary
hops.

page_text: As before stated every brewery can carry out the treatment of hops according
to our Invention, as a treatment with sulphur such as is necessary with every other
existing process is not required. No definite proportions of the alcohol used can
be given, as this is entirely dependent on the quality of the hops to be used, and
can only be determined by experiment.
Having thus described the nature of our Invention, and in what manner the
same is to be performed, we claim,—
First. The method, substantially as herein set forth, of preserving hops by
treatment with alcohol.
Second. The use of hops having an admixture of alcohol for the preservation
thereof.
In witness whereof, I, the said Carl Pohl, have hereunto set my hand and
seal, this Sixteenth day of September, in the year of our Lord One thousand
eight hundred and seventy nine.
AUTY TARY