IN THE STORAGE CASKS. 107 



the cells had been counted, this would indeed have been found 

 to be the case ; it must not, however, be forgotten that the 

 result does not depend merely on the number of yeast cells, 

 but also on the species and on their condition. It would be easy 

 to suggest an explanation ; but as I have made no experi- 

 ments on which to support it, I prefer to merely state the facts. 



This, then, was the point with reference to average 

 samples. The experiments show that, as a rule, the brewer 

 will not obtain fair samples when he draws them in the 

 ordinary manner from the lower portion of the cask. 



The next point to be mentioned is the method which we 

 must employ in order to ascertain how long the beer will 

 remain sound under the conditions to which it is exposed 

 after bottling. We will here assume that it is properly 

 handled both in the carriage casks and in bottle. In the case 

 of ordinary lager beer, the temperature to which it is exposed 

 is, as a rule, not higher than the ordinary room-temperature, at 

 any rate under the conditions prevailing in Denmark. In the 

 case of export beer, on the other hand, the matter is different, 

 and this is furthermore required to remain sound for a much 

 longer time. The brewer, therefore, is also in the habit of 

 exposing his samples of lager beer to the ordinary room- 

 temperature, whilst he subjects the samples of export beer to 

 a higher temperature e. g. 25 C. 



In transferring the beer from the store casks to the trans- 

 port casks, and from these again to the bottles, it becomes 

 moderately freely aerated, and thus one active factor will be 

 furnished for bringing about the multiplication of the yeast 

 cells. When the beer is drawn off by means of compressed 

 carbonic acid gas, this will, of course, be avoided ; but it is 

 only exceptionally that this method is adopted. 



The samples in our bottles are, in consequence of what 

 has been stated above, less aerated than the beer occurring in 

 commerce ; that this influences the stability is proved by the 

 following experiments. 



