54 The Fermentation of Cacao 



cent, acetic acid containing from 3 to 5 per 

 cent, of alcohol in order to imitate the com- 

 position of the fermenting pulp juice. After 

 twenty to thirty hours' digestion of pulped cacao 

 at 40 to 44 C. it was observed that the pulp 

 had died and shrunk to skinny masses, partly 

 separating in small pieces, but mostly still 

 firmly adhering to the 'testa. It appears that 

 for bringing about an easy separation of the 

 dead pulp from the testa a bacterial enzyme is 

 necessary, as in the case of coffee fermenta- 

 tion. It was further observed that the amount 

 of acetic acid, which entered by osmosis 

 through the testa to the cotyledons, was not 

 sufficient to kill the oxidizing enzyme, since the 

 freshly cut surface of these seeds rapidly turned 

 brown on exposure to the air. On the other 

 hand, it was observed that when the freshly 

 cut surface of the seeds so treated was moist- 

 ened with 4 per cent, acetic acid no further 

 change by oxidation took place. In this case 

 the oxidizing enzyme was killed. 



It is stated by Hart 1 that " of late years 

 there has been a large amount of inquiry for 

 cacao which is but slightly fermented or not 

 fermented at all." This renders it very pro- 

 bable that the decomposed juice of the slime 

 tissue is not required for the generation of the 

 aroma, as was supposed. Indeed, the true 

 aroma of cacao is faint before roasting the 

 fermented beans. The case is, therefore, 



1 " Cacao." Trinidad, 1900, 2nd ed., p. 33. 



