i8o "DISEASES" OF BEER, 



the prevalence of the disease known as yeast turbidity. He 

 writes : " The finished lager beer is drawn off from the store 

 cask in the cool cellar, apparently perfectly bright, but it soon 

 becomes cloudy in the bottles or casks when placed in a 

 warmer situation, or during transport. The examination of 

 such beers, then, reveals small yeast cells which rapidly 

 develop and increase and finally completely settle. Brewers 

 call this yeast light yeast (Flughefe)" Lintner considers that 

 the cause of this is to be attributed to the influence which 

 an inferior malt may have on the nourishment of the yeast, 

 partly also to an insufficient quantity of yeast having been 

 added to the wort, and to the fermentation having been con- 

 ducted at too low a temperature. Lintner assumes that 

 under such conditions the normal brewery yeast suffers some 

 undesirable transformation, which causes it to develop these 

 small light cells, and that the resulting disease is thus ex- 

 plained. He regards the theoretical speculation of Nageli as 

 supporting the correctness of this view. In the year follow- 

 ing he repeated the same opinion,* 



As will be remembered, it was formerly held that the 

 disease mentioned was caused by Sacch. exiguus. This view 

 had been completely discarded in 1881, and the cause of this 

 and similar diseases is now no longer sought in foreign yeasts, 

 arid in contamination occurring from without, but in the con- 

 ditions as regards nourishment under which the good brewery 

 yeast is placed. After the doctrine of Reess and Pasteur 

 failed to help brewers, both Lintner and Holzner appealed to 

 the physiological theories of Nageli in the hope of obtain- 

 ing light on the subject. Most of the zymotechnologists of 

 that time adopted similar views, as also did Delbruck and 

 Hayduck in Berlin. Discussions now arose concerning the 

 degeneration and transformation of brewery yeast, and it was 



* C. Lintner, sen., " Altes und Neues iiber Bierbrauerei, " ' Zeitschr. f. das ges. 

 Brauwesen,' Munich, 1881, p. 153. 



