CHAPTER V. 



ALCOHOLIC FERMENTS. 



INTRODUCTION. 



TT does not lie within the scope of a work of this description 

 to give a detailed summary of the knowledge of bygone times; 

 it will suffice to pass in review as much only as is necessary 

 for the proper understanding of the present position of the 

 subject under discussion. As the investigations of the last 

 decade originated essentially from questions connected more or 

 less directly with practice, the results obtained are also fully 

 entitled to a practical application. It is evident, however, 

 that this can only be brought about when the essential results 

 of these scientific investigations are thoroughly appreciated ; 

 and it is with the object of facilitating this that the following 

 resum6 is given. 



The term alcoholic ferment, as commonly used, is very 

 comprehensive. Mould-fungi, as well as bacteria and budding- 

 fungi, are able to induce alcoholic fermentation; but here we 

 have only to deal with the last-mentioned. Among these 

 budding -fungi are some which also develop mycelium, while with 

 others this form of growth does not as a rule occur ; among the 

 latter an important group is included under the name Saccharo- 

 mycetes, on account of the property which its members possess 

 of forming endogenous spores. 



In the year 1839 SCHWANN found that in the case of 

 certain yeast-cells new cells were formed in their interior, and 

 that these were liberated through bursting the walls of the 

 mother-cells. J. DE SEYNES (1868) was, however, the first 



