i;2 "DISEASES" OF BEER, 



was, however, not the case with Cienkowski.* The latter 

 considered that Reess's species of the Saccharomycetes were 

 only forms of development of Mycoderma vim. Several other 

 investigators expressed an almost identical view, as, for 

 instance, Harz in his ' GrundzUge der alcoholischen, Garungs- 

 lehre/ 1877. This standpoint was perfectly justifiable since 

 the basis of Reess's description of species was, as we have 

 seen, quite untenable. If, with this altered view, there could 

 be any question at all of the yeast cells themselves producing 

 diseases, this would, at any rate, have to be regarded from 

 quite a different point of view from formerly. It was no 

 longer a question of foreign species gaining admission from 

 without to the wort and beer, and here competing with the 

 brewery yeast, but the whole question had to be attacked 

 from quite a different direction. It could then only be a 

 question of a deterioration of the brewery yeast itself under 

 different conditions of nourishment. Regarded from a 

 practical point of view the problem was therefore restricted 

 to determine these chemical conditions. 



These important questions were discussed again and 

 again without any decisive experiments having been made. 



In 1876 appeared Pasteur's famous work on beer and 

 its diseases.! It will be recollected that in his studies on 

 wine, Pasteur showed that a number of its diseases are 

 caused by bacteria. In his new work (pp. 47) he proved that 

 with beer the case is similar. The fact must also be empha- 

 sised that by means of exact experiments, he furnished a 

 complete proof of the correctness of this doctrine (pp. 20 and 

 26). He came to the conclusion, so important in practice, 

 that any bacterial growth which can attack wort or beer, must 

 be regarded as dangerous, and that every precaution must be 

 taken to exclude bacteria as far as possible. As these small 



* Cienkowski, " Die Pike der Kahmhaut " ' Bulletins der Petersb. Akademie,' 

 t. xvii. 1873. 



f Pasteur, ' Etudes sur la bieie,' Paris, 1876. 



