AN IMPROVED METHOD OF TREATING FISH SO AS TO PRESERVE IT IN A FIT STATE FOR FOOD
Year: 1882

page_text: LETTERS PATENT to Carl Pieper, Civil Engineer and Patent Agent, of
109-110, Gneisenaustrasse, Berlin, S.W., Prussia, for an Invention of "AN
IMPROVED METHOD OF TREATING FISH SO AS TO PRESERVE IT IN A FIT STATE
FOR FOOD." A communication from Johannes Hugo Gustav Walkhoff, of
Hamburg, German Empire.
PROVISIONAL SPECIFICATION left by the said Carl Pieper at the Office of
the Commissioners of Patents on the 9th January 1882.
CARL PIEPER, Civil Engineer and Patent Agent, of 109/110 Gneisenaustrasse,
Berlin S.W., Prussia. AN IMPROVED METHOD OF TREATING FISH SO AS TO
PRESERVE IT IN A FIT STATE FOR FOOD. A communication from Johannes Hugo
Gustav Walkhoff, of Hamburg, German Empire.
i
The object of the present Invention is, to preserve fish for a considerable period
without appreciably detracting from its original flavour, and for this purpose the
inventor employs a method in which certain means otherwise individually used
with the same intent, are combined in a novel manner.
The fishes are first of all put for some time into salt. Their entrails having then
been taken out, they are exposed for about two or three days to a drying process.
Hereafter they are smoked until they have attained a bright yellow colour, and
thus prepared they are packed into tin boxes or other vessels which are thereupon
filled with sweet-oil with or without the addition of spices or aromatic fruits.
Finally, the said boxes or vessels are hermetically closed and for some time
exposed to a moderate heat, by preference in a water-bath.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent and
of an Order of the Lord Chancellor filed by the said Carl Pieper in the Great
Seal Patent Office on the 14th July 1882.
CARL PIEPER, Civil Engineer and Patent Agent, of 109/110 Gneisenaustrasse,
Berlin S.W., Prussia. IMPROVEMENTS IN THE PRESERVATION OF
FISHES.
A communication from Johannes Hugo Gustav Walkhoff, of Hamburg, German
Empire.
Heretofore fishes have been preserved by smoking, salting or drying them, by
pickling them in vinegar, by treating them with saltpetre, borate of soda, salicylic
acid or sulphate of alumina, by impregnating them with carbonic oxyde, by putting
them into tallow, oil, &c. But these methods have the disadvantage of almost
entirely changing the flavour of the fish, or of imparting to it a peculiar strong
taste or of not allowing the fish to be kept in a good state for a length of time.
The object of the present Invention is, to preserve fish for a considerable period
without appreciably detracting from its original flavour, and for this purpose the
inventor employs a method in which certain means otherwise individually used
with the same intent, are combined in a novel manner.
For carrying the Invention into effect, the fishes, soon after having been caught
and killed, are put into strong brine or packed into barrels together with dry salt.
After they have become sufficiently impregnated with the salt, their entrails are
taken out. This may be done by laving hold of the pectoral fins near their base
and tearing them away with a slight twist, as this manipulation will cause the
intestines to follow so that they can then easily be drawn out also.
The fishes are thereupon exposed for two or three days to a drying-process,
which is carried out, according to the state of the weather, either in the open air
or in suitable chambers, and hereafter they are smoked over a low fire of wood,
which may partly be kept up with saw-dust or tanning-bark, until they have
attained a bright yellow colour with a golden tinge, but care must be taken not to
roast them. The fishes are then packed, by preference with their back downward,
into tin boxes or other vessels, whereupon sweet-oil, i.e. any eatable oil, is poured
over them, so that it fills the boxes or vessels to the brim. Spices, such as cloves,
laurel-leaves and others, or aromatic fruits, as for instance tomatoes and paradise-
apples, may besides be added, if desired. The boxes or vessels, having been
hermetically cloved by soldering or in other known manner, are finally exposed
for some time, according to the method of Appert, to a moderate heat, by preference
in a water-bath, for the purpose of killing all fermentible germs and, besides, of
causing the oil and the taste of the spices to better penetrate into the flesh of the
fish.
When fishes are treated according to this Invention, their natural taste is but
very little altered, they may be skinned with facility, and they keep unaltered for
a number of years.
Having thus described the nature and object of this Invention and the manner
in which it is carried out in practice as communicated to me by my correspondent,
I hereby claim as new and important features of the Invention :
The method of preserving fish, consisting in a combination of the operations of
salting the fish, of removing its entrails, of drying and smoking it, and of packing
the same together with sweet-oil and with or without the addition of spices or

page_text: aromatic fruits into suitable vessels, which, after having been hermetically closed,
are exposed to a moderate heat, substantially as and for the purpose described.
In witness whereof I, the said Carl Pieper, have hereunto set my hand and
seal this Twenty first day of June in the year of our Lord One thousand
eight hundred and eighty two.
CARL PIEPER. (L.S.)