Cocoa By-Products and Their Utilization as Fertilizer Materials

Excerpts from the report Introduction: As a result of an interesting economic situation, related to the existing great demand for cacao butter, there are now in the United States three trade residues produced from cacao beans where formerly the husks or shells were the only regular by-product of commercial importance. The two recent arrivals in this field are by-product cocoa press cake and solvent-extracted cocoa, and their advent in important quantities has created renewed interest in the utilization of cacao by-products. All three by-products are available at prices which put them within the reach of the fertilizer industry. One of these potential fertilizer materials, the by-product cocoa cake, is nothing less than the press cake remaining from the manufacture of cacao butter. The enormous demand for cacao butter has resulted in a great surplus of this by-product cocoa press cake, and thousands of tons of the product have had so low a market value that some of the material has been burned under the factory boilers. Its low price has made the cake available for use as fertilizer material, and at least two manufacturers of mixed fertilizers have given the product a trial as a rough ammoniate filler and conditioner in their mixed goods. A certain quantity is being subjected to extraction with a fat-solvent for the recovery of the cacao fat remaining in the cake after the hydraulic pressing, and this solvent-extracted cocoa residue also is available for utilization as fertilizer material. The surplus cocoa cake has been used as a source of the alkaloidal base theobromine and it has also been tried as an ingredient of cattle feed. In view of the quantities of these cocoa by-products available and the dearth of published information relative to their production, chemical composition, and the properties of their nitrogen-bearing constituents, an investigation of their nature and their value as fertilizer material was undertaken.