222 The Fermentation of Cacao 



" diseases " of wines, in which, instead of a 

 proper fermentation taking place, souring 

 occurred. This he showed to be due to the 

 presence of undesirable organisms ; soon after 

 this, methods were discovered by which the 

 organisms that brought about the required 

 changes could be separated from the more 

 adventitious ones. This was a great stride, 



o 



but it has not yet been fully utilized or even 

 appreciated. 



The "sweating," as the fermentation of 

 cacao is called, is brought about by some of 

 the many varieties of yeasts, and to a greater 

 or less extent by other organisms, acting upon 

 the saccharine pulp which surrounds the seed. 



If a minute fragment of baker's yeast is 

 shaken up in a little water, and a drop of the 

 resulting emulsion is placed under the micro- 

 scope, it will be seen to consist of many 

 thousands of round or oval cells, each of which 

 is an independent organism which has the 

 power of growth and reproduction. The 

 latter is brought about by what is known as 

 4 'budding" : a small protuberance appears on 

 the surface of the cell and continues to increase 

 in size until it is as big or nearly as big as the 

 cell from which it springs ; it then splits off, 

 and thus two cells are formed, each of which 

 again starts budding. In very actively growing 

 yeast this form of reproduction takes place 

 about once every half-hour and thus theoreti- 

 cally by geometrical progression one cell will 



