COCOA BY-PRODUCTS 39 
three materials (Tables 2. 4, and 5), the relative market values 
are found to be as follows: (1) By-product cocoa press cake of 
average composition would bring 20 per cent more per ton than 
commercial cocoa shells like the samples; and (2) dried solvent- 
extracted cocoa would bring 50 per cent more per ton than these 
shells. For use as fertilizer material, average press cake, therefore, 
might be expected to bring 80 per cent of the price of the solvent- 
extracted cocoa per ton. 
Shells with a lower ammonia content would, of course, have a 
relatively lower market value than those represented by the sam- 
ples examined, on which the foregoing estimates were based, since 
the market price is mainly dependent on the content of ammonia. 
SUMMARY 
Until a few years ago the only cacao by-product in the United 
States having a sufficiently low market value to be available to the 
fertilizer manufacturer was the shells, with such related waste 
material as cocoa dust and sweepings. As a result of the enor- 
mous demand for cacao butter, two additional by-products of im- 
portance are now being produced in large quantities and are avail- 
able at prices which make them of interest as fertilizer materials. 
These are the by-product cocoa press cake and solvent-extracted 
cocoa. The latter is the defatted residue left after extracting the 
cacao fat from the press cake with benzol. 
It is estimated that the annual production of by-product cocoa 
cake was between 15.000 and 21,000 tons in 1923, and 25,000 tons 
in 1924. Two main types of press cake are being produced : The 
more common, higher fat content sort; and the dry-pressed cake, 
which is turned out by very powerful presses and has a much lower 
percentage of fat. A certain quantity of cocoa dust and fine waste, 
also, is pressed for its fat, resulting in a lower grade of press cake. 
A single cursory factory test indicated that under certain con- 
ditions a better yield of fat could be obtained by grinding and 
pressing whole cacao beans. 
Quantities of the cake of the higher fat content types are utilized 
for recovery of the fat by solvent extraction, and a part of the 
low-fat type has been in demand for use as raw material for the 
preparation of the alkaloid theobromine. 
Including the cake subjected to solvent extraction, the residue 
from which is utilized as fertilizer material, it is estimated that at 
least one-fourth of the by-product cake produced is eventually con- 
sumed in fertilizer. A smaller quantity was used in mixed feeds 
during 1924 ; and some was used in the preparation of theobromine. 
Some by-product cake has been burned as fuel by the manufacturers. 
Utilization of cocoa by-products as fertilizer materials, there- 
fore, is in more or less active competition with their use as feed 
stuffs, as sources of the alkaloid theobromine, and to a lessening- 
extent as fuel. 
The few tests that have been reported in the literature on the 
feeding value of cocoa cake show that it depresses" the milk flow 
of dairy cattle. xV review of the literature leads to the conclusion 
that caution should be observed in feeding cocoa products to ani- 
mals, especially to nonruminants. 
