36 COCOA 



CHAP. 



agreeable taste and smell. Chemically it is a mixture 

 of glycerids of different fatty acids, and consists 

 principally of stearin, palmitin, laurin and also the 

 glycerid of arachin-acid. 



The qualities of this substance vary according to 

 the manner in which it is obtained i.e. whether by 

 extraction (by means of ether or other solvent fluids) 

 or by pressure. The specific gravity of the extracted 

 butter is about 0'95 to 0*99; of the pressed butter, 

 0*85. The melting-point of the latter, when kept for 

 some time, is 34 to 35 C. ; the melting-point of the 

 former is slightly lower. The melting-point of 

 unadulterated cocoa -butter is never below 32 and 

 never above 35. 



The fat is contained not only in the kernels but 

 also in the cuticles, from which it is also obtained by 

 extraction and comes to the market as a second-quality 

 cocoa-butter. 



TJieobromine. The methods formerly applied by 

 analysts for determining the amount of theobromine 

 were all more or less imperfect, and accordingly widely 

 varying figures were obtained. These methods were 

 critically reviewed by Dekker, 1 who invented a new 

 and reliable method. The complete unreliability of 

 the results obtained by the old methods may be seen 

 from the figures obtained by four analysts, the amount 

 of theobromine contained in one sample of cocoa : 071 

 per cent (method of Kunze), 0*81 per cent (method of 

 Zipperer), 2'00 per cent (method of Beckurts), 278 

 per cent (method of Bell). It turned out, however, 

 that the real quantity (by the Dekker method) 

 amounted to 1*69-173 per cent. By the methods 

 of Kunze and Zipperer part of the theobromine was 

 destroyed, and therefore the figures obtained were 

 too low ; by the methods of Beckurts and Bell the 

 theobromine obtained was not pure, and accordingly the 

 figures obtained were too high. 



1 fiber einige Bestandteile des Cacao und ihre Bestimming : Inaugural- 

 dissertation (Amsterdam: de Bussy, 1902). 



