10 BULLETIN 1413, U. S. DEPARTMENT OF AGRICULTURE 
fatty substances, when present in appreciable quantities, tend to 
lower the availability of the fertilizer constituents to growing plants, 
by coating the particles containing plant food with an impervious 
envelope and thus impeding their decomposition and solution. 
The proportion of the total by-product cake that has been directly 
consumed as fertilizer material is not accurately known. State- 
ments obtained from producers and fertilizer men indicate that 
at least 3,000 tons have been sold for utilization as fertilizer within 
a year. If the cake that is subjected to solvent extraction for the 
recovery of the cacao fat, the residue from which finds its way into 
the fertilizer trade, be included also, probably at least one-fourth of 
the total quantity of by-product cake produced is eventually con- 
sumed as fertilizer. 
Information as to the quantity of cake commercially extracted for 
recovery of the cacao fat was obtained; but inasmuch as only one 
establishment is engaged in this undertaking, the data can not be 
divulged. 
Large quantities of low-grade cake have been burned under the 
manufacturers' boilers in the past; but the monetary value to be 
credited to the product from such disposal is small, and it is be- 
lieved that only a few hundred tons were burned during 1924. 
A small portion of the by-product cake produced has been con- 
sumed as raw material for the preparation of theobromine. As not 
more than two concerns are known to be using cocoa for this pur- 
pose, the exact quantity that is being used can not be stated. 
Not less than 1,200 tons of the press cake was disposed of to 
mixed-feed manufacturers during 1924, and there are reasons for 
believing that the quantity of cocoa cake consumed in feeding stuffs 
for animals is on the increase. 
The definite figures on which the foregoing estimates are based 
account for only about one-half of the by-product cocoa cake pro- 
duced annually. As all of the known outlets for the cake of any 
commercial significance have been mentioned, however, it seems 
likely that the balance must have been disposed of through the same 
channels, or wasted outright. 14 Attempts have been made, so far 
without any great success, to market some of the better grade of 
surplus cake as an ingredient of bakery goods. Cocoa bread and 
wafers have been produced, but the tonnage of cocoa consumed in 
this way is negligible. 
It has been suggested that certain manufacturers have endeavored 
to market pulverized low-fat cake as powdered cocoa for human 
consumption. This is beside the point, however, as the present 
study is concerned with the material held so cheaply by the producer 
as to give it a market value placing it within reach of the fertilizer 
trade. 
COMPOSITION AND PROPERTIES 
The literature of cacao contains much information on the com- 
position and nature of cocoa from the viewpoint of its use as a 
beverage and food; but, with the exception of reports on the ex- 
14 Information to the effect that some low-fat cocoa cake and powder is shipped to 
northern Europe was volunteered by the warehouse manager of a Norfo k. Va., brokerage 
firm that had dealt largely in cocoa by-products, but the writers !. n vv been unable to 
confirm this statement. 
