84 STORRS AGRICULTURAL EXPERIMENT STATION. 
careful comparison may be made. Sometimes one was inoculated 
with one species and the other with another. Sometimes one was 
left without inoculation for control. The inoculated cream was 
then allowed to ripen at varying temperatures and for varying 
lengths of time. The temperatures which have been adopted 
have been 20° C. (68° F.) and 24° C. (75° F.), and the length of 
ripening has been usually 24 hours, though in some cases 48 
hours. After the ripening a careful examination of the ripened 
cream was made, the cream was churned and the butter also care- 
fully examined as to taste and flavor, both with and without salting. 
With each of the organisms above described several experiments 
have been performed, in most cases eight to ten, and in all cases 
enough to bring about uniform results. Where a half dozen 
experiments followed each other with absolutely uniformity the 
organism in question was no longer experimented with, but an- 
other was taken. But whenever any lack of uniformity arose in 
the results of the first half dozen experiments, the experiments 
with the organism were continued until absolute uniformity was 
reached. In this way the effect upon the butter of ripening 
the cream with each organism was determined accurately. In 
the following descriptions it is not thought necessary to give the 
details of each of these experiments. Most of the 200 are 
duplicates of each other, and the essential results can be given 
just as well by describing a few experiments as by describing 
them all. It will be, of course, understood that in the following 
descriptions we have results which have been confirmed in every 
case by a series of experiments, and in no cases are the results 
of experiments isolated ones. They may, therefore, be re- 
garded as accurate so far as this method of experimenting with 
pasteurized rather than sterilized cream makes accuracy pos- 
sible. 
Species No. 34. 
At atemperature of 20° for 24 hours or 36 hours the cream 
is scarcely changed. It remains thin and limpid, although it 
acquires a very slight acid reaction and a slight sweet taste. 
The butter made from it is good, but mild. It shows no decided 
flavor and lacks the desirable aroma present in properly ripened 
butter. It is, indeed, very similar to butter made from unripened 
cream. No. 34 is, therefore, a neutral species whose presence in 
normally ripened cream will have no great influence. 


