PRODUCED BY ALCOHOLIC FERMENTS. 177 



treatise. I have not only emphasised the important advances 

 brought about by the discoveries of the famous French savant^ 

 but have also given the reasons why they were unable to 

 bring about the solution of the two important problems of 

 the diseases of beer and pure cultivated yeast. By means of 

 the method recommended by Pasteur, the good brewery yeast 

 became suppressed and the growth of the disease yeast pro- 

 moted. It was, indeed, not possible to achieve success by 

 the means which he adopted. 



In the same year in which Pasteur's ' Etudes sur la biere ' 

 appeared, Lintner, sea, published the results of some zymo- 

 technic experiments.* He described various irregularities in 

 the fermentation and diseases in the beer, which were a source 

 of great trouble and loss to the breweries in which they 

 occurred. The microscopic examination gave no information, 

 and Lintner, indeed, states that a yeast which, judged by this 

 test, would be regarded as satisfactory, nevertheless gave a 

 bad result in the brewery. On the other hand, he obtained 

 a good result with another yeast which a microscopic exam- 

 ination indicated to be unsatisfactory in that it contained a 

 number of small and irregular cells (light yeast). This objec- 

 tionable-looking yeast, nevertheless, gave perfectly normal 

 fermentations, and was employed with decided success in 

 different breweries. In fact, this forms an excellent illustra- 

 tion, showing how little information is gained in this field by 

 a simple microscopic examination alone. A more rigorous 

 criticism of the methods of examination then in vogue can 

 scarcely be imagined. 



* C. Lintner, sen., " Ueber einige Resultate zymotechn. Untersuchungen," 

 'Zeitschrift f. das ges. Brauwesen,' Munich, 1876, p. 221. 



t Such inadequate methods are unfortunately still made use of in several 

 brewery-laboratories, and, what is still worse, theories are built up upon then; 

 and are boldly expounded with the conceit which characterises the half-scientific 

 literatiire. 



Most of the brewing journals are only too ready to open their columns to such 

 articles. This half-scientific literature has continued up to the most recent times, 

 one communication after another appearing on "light yeast" and "degenerated " 



N 



