86 MICRO-ORGANISMS AND FERMENTATION. 



wine, beer, and wort so viscous that they can be drawn out in 

 threads. 



KRAMER has described a Bacillus viscosus sacehari, which 

 in a short time converts a cane-sugar solution into a slimy 

 tough mass. Another species, which makes beet juice slimy, 

 at the same time producing an ethyl alcohol fermentation, was 

 described by GLASER under the name of Bacterium gelatinosum 

 letce. 



CRAMER isolated a Bacterium viscosus vini, which was 

 cultivated in sterile wine, air being excluded. Wines into 

 which this growth had been inoculated grew thick in the 

 course of six to eight weeks. This species grows best 

 at 15-18 C., and seems to die at as low a temperature as 

 30 C. 



In Berlin " Weissbier " (white beer), which had turned ropy, 

 LINDNER found a strong development of a certain Pediococcus. 

 The disease could be produced by adding pure cultures to 

 sterilised white-beer wort. On the other hand, this organism 

 had no action on hopped beer-wort or low-fermentation 

 beers. 



In ropy Belgian beer VAN LAER found the cause of this 

 disease to be small, very thin rods (1'6 to 2 '4 micro-milli- 

 meters long), which were partly isolated and partly united in 

 pairs by means of a zoogloea-like substance. When added to- 

 beer-wort, this first became turbid, and afterwards ropy. On 

 meat decoction with gelatine these rods gave colonies with 

 concentric rings of different colours and with a hollow in the 

 middle ; streak cultures give broad, white bands, with a 

 sinuous border ; puncture-cultivations give a white stripe, 

 soon extending to the bottom of the glass ; the gelatine forms 

 fissures which become filled with the growth, while at the same 

 time a speck is formed on the surface. Experiments carried 

 out with pure cultures of this bacterium in beer-wort have 

 shown that one and the same form includes several species, 

 which have a somewhat different action on wort. They are all 

 included under the name Bacillus viscosus. If sterilised wort 

 is infected with this bacterium and alcoholic yeast added after 

 the lapse of some hours, the liquid becomes viscous. If 

 the wort is infected with a mixture of absolutely pure yeast 



