126 TECHNICAL ANALYSIS OF 



and those in which the micro-organisms took several days 

 (e. g. five or more days) to develop. Since the germs deve- 

 loped so slowly in these last flasks, there is reason to believe 

 that they would not have developed at all if they had been 

 introduced into the fermenting vessels or into storage casks, 

 It is therefore only in that group of cultures in which the 

 development had been rapid that we have to look for the 

 bacteria and wild species of yeast which are likely to prove 

 dangerous to the beer. The numbers found thus become 

 further reduced, and, as stated, we approximate still more 

 closely to the practical conditions which actually obtain in 

 the brewery. To imitate these exactly is, of course, not 

 possible, and we must be content with having approximated 

 the desired end as closely as is really the case. The question 

 of the effect of competition will vary not only according to 

 the different methods adopted in different breweries, but also 

 according to the varying composition of the wort in one 

 and the same brewery in the course of the year. 



In spite of all these restrictions, however, the described 

 analysis gives us valuable information, and, as we have seen, 

 of a kind which we can only gain in this way. It is important 

 here to point out that by cultivation in our flasks of wort we 

 are able to obtain growths of all micro-organisms which we 

 know with certainty are able to produce diseases in beer. As 

 has been already stated, several of these disease-organisms, 

 on the other hand, do not develop at all when introduced into 

 the beer. If they are to make themselves felt and produce 

 sickness, they must be introduced into the fermenting wort. 

 For this reason the cultivation in beer becomes of less moment 

 for the analysis, and the cultivation in wort of by far the 

 greatest importance. If we employ the method described 

 with care, we shall thus be in a position to discover the 

 enemies that are present amongst the microscopic germs 

 which gain admittance to the brewery with the air and with 

 the water. The fault which we are in danger of committing 



