550 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
The inventor states that a barrel of menhaden yields about 3 pounds of the 
extract, that the article compares favorably with Liebig’s extract of beef and retains 
its flavor under any ordinary condition of temperature or climate. While it has never 
been prepared for the general market, it seems not improbable that it might have a 
considerable patronage if iiroperly introduced. 
A somewhat similar process was invented* in 1882 by Oarl Adeljih Sahlstrom, of 
Jonkoping, Sweden, for producing a nutritious extract from the flesh of the shark, 
whale, seal, and other sea animals. This process was as follows: 
The raw material is cut up into as small pieces as possible by mechanical means and is placed in 
a vat provided with stirring apparatus. A quantity of clean water, free from lime, is boiled and 
cooled down to from 6° to 15^ C., and to this is added so much dissolved bypermanganic alkali as 
will impart to the water a light-red color (say from 1 to 10 grams for every 100 liters of water) 
and from 20 to 100 grams of water of ammonia. Sufficient of this liquor is added to the finely cut 
raw material to give thereto the consistence of thin gruel, and the stirring apparatus is then set to 
work. After a period of from 10 to 30 minutes the mass is removed from the vat and is placed in a 
centrifugal apparatus for the purpose of separating the liquor, which carries the fat with it. The inner 
part of the centrifugal apparatus is preferably covered with cloth. When all the fiuid is separated 
the mass is again soaked in fresh liquor and passed through the centrifugal apparatus, and this is 
done as often as may be necessary to remove all the fat. All the fluid obtained is mixed together and 
left to stand in a deep tank for a period varying according to the temperature and until complete 
separation takes place. The fat and oil rise to the top of the liquid and are removed for further 
treatment. The oil is separated for special treatment. The solid mass remaining in the centrifugal 
machine is also reserved for further treatment. The fluid thus obtained, free from any 2 iarticle of fat, 
is then mixed with 1 to 10 grams of common salt to each 100 liters of the fluid, is boiled as quickly as 
jmssible until the albumen coagulates, and is then filtered. The clear fluid is evai)orated in vacuo or 
otherwise till it attains the consistence of treacle. It is then poured into a shallow vessel, which can 
1)0 heated by steam. From 0.1 to 8 per cent of sugar is then added, for the purpose of preserving the 
extract and of imparting a taste thereto similar to that of Liebig’s extract of meat. The extract is 
heated to a temijerature of 100° C., and kept constantly stirred until the desired consistence is 
attained. Vegetables or extracts thereof, or any other flavoring matter, or flour or other material 
for imparting a higher nutritive power or to give solidity, may be added at 2 )leasure. 
A factory was established at Aberdeen, Scotland, in 1885, under the superinten- 
dence of Sahlstrom, in which quantities of the extract were prepared from whale 
flesh. It was reported that the product possessed no flavor of the crude flesh what- 
ever, and was quite similar to that prepared from ox flesh. It does not appear that 
anything is done in this line at present. 
In a discussion of extracts of fish, published in 1885, Prof. William Stirling, of 
Owens College and Victoria University, Manchester, states: 
The Normal Company, under the superintendence of Mr. Sahlstrom, has recently established a 
factory in Aberdeen, and has manufactured large quantities of a similar extract from whale flesh. 
This extract presents all the characters of an extract made from the flesh of the ox. Such an extract 
forms an excellent basis for a soup, having all the flavor of an extract of ox flesh. But extracts of 
fish can be made in a similar way, the product being, as far as sensible characters are concerned, 
indistinguishable from that of ox flesh. These are points of difl’erence dejiending on the slightly 
different chemical composition of fish and flesh; for, even in the same animal, there is a difference in 
the chemical composition of individual muscles. Such fish extracts have no flavor of fish whatever, 
and possess all the aromatic flavor of meat extract, and I understand that they can l)e made much 
more chea 2 )ly than extract of meat. At a certain point in the process of extraction all the fishy 
flavor disajjpears. As a. general rule, these extracts are made by boiling a watery extract of the fish 
muscles, after acidulation and jirecipitation of the proteids or alluimins, in an open vessel with a 
double jacket, so that steam can be admitted between the layers of the jacket, and thus keej) up 
* Letters Patent No. :153822, dated December 7, 1886. 
