136 WHAT IS THE PURE YEAST OF PASTEUR? 



Australia by De Bavay, and in North France and Belgium by 

 Kokosinski, Van Laer and Vuylsteke (" Station Scientifique 

 de Brasserie," ' Comptes-rendus,' Gand, 1 890, p. 1 3-2 1 ; ' La 

 Gazette du Brasseur,' Bruxelles, 1890). Even in France my 

 method has been successfully introduced into fifteen high- 

 fermentation breweries, and its employment is therefore not 

 confined, as Duclaux believes, to low-fermentation breweries. 

 The reader may also be referred to the account in a subse- 

 quent chapter of the extent of the application which my 

 system of pure yeast culture has now acquired.* 



Velten commenced his attacks against myself in the 

 lectures which he delivered at the French Brewers' Exhibition 

 in Paris in 1887 (' Revue Universelle de la Brasserie et 

 Malterie,' 1888, No. 742 and 743), and he repeated them at 

 the Antwerp Congress in 1889 (see Report, p. 82). He main- 

 tained that I made a great mistake in introducing yeast con- 

 sisting of a single species or race into the brewery ; according 

 to his view, brewery yeast should consist of several species, 

 and in reference to this he expresses himself as follows : " It 

 is to the mixture of these pure species of yeast, different in 

 their race and in their nature, that beer acquires the desired 

 taste and bouquet." This result, he states, is obtained by the 

 employment of Pasteur's method, namely, by cultivating the 

 yeast in a solution of cane sugar to which a little tartaric acid 

 has been added, or in wort containing carbolic acid and 

 alcohol. He gives no further particulars of the method in 

 the lectures mentioned, but these are to be found on referring 

 back to the lectures which he delivered at the Paris Exhibi- 

 tion in 1878, and which were afterwards published under the 

 following title : " De la fabrication de la biere par le precede 

 Pasteur. Conference faite par Eugene Velten au Congres 



* Addition 1895. As shown in a subsequent chapter the pure yeast cultiva- 

 tion in top fermentation has been much more widely propagated since I wrote the 

 above. Up to recent times Van Laer employed my system in its simplest form, 

 but now in a more complicated and uncertain manner, in that he recommends a 

 composite yeast. The same is also the case with Vuylsteke. 



