
BACTERIA IN THE DAIRY. bo 
secondary facts regarding the best methods of handling the 
organism in ripening cream. ‘The most of these details concern 
practical dairying rather than bacteriology, but some of them 
may be properly mentioned here. It has appeared that cream 
ripened with this organism needs to be churned at a little lower 
temperature than ordinary cream to produce the best results as 
to body, grain, and flavor. A churning temperature as low as 
52° to 54 is sometimes needed in order to produce the best 
butter and the highest flavor. Again, it has been found (first 
in laboratory experiments) that it is possible to keep cream 
sweet for a longer period by the use of the culture than with- 
out it. In my laboratory cream has been kept for nearly two 
weeks without becoming very sour, while cream that was not 
thus inoculated soured much more quickly. As one result 
of this fact, it has been found by butter-makers that cream 
does not sour so readily after it is inoculated with Bacillus No. 
41, and that to a certain extent the souring already begun may 
be checked. ‘The buttermilk that is made from cream ripened 
with the organism is, therefore, sweeter and keeps for a longer 
time than ordinary buttermilk. A very important practical 
matter has developed in the use of different lots of cream, 
namely, that cream from different patrons of the same cream- 
ery ‘differs very much in character, and that when the first 
small lot of 6 quarts is taken as a starter it makes some differ- 
ence whether this cream is taken from one source or from 
another. In some cases it has been found that the general 
iiimowmcrenin, 2, ¢., the’ mixed cream in the creamery, 1s not 
properly fit to use for this purpose, and to obtain the best cul- 
ture, and consequently the best results with Bacillus No. 41, it 
is necessary to use cream from some special patron for the first 
starter. This is easy to understand, inasmtich as the mixed 
cream in the creamery will be frequently impregnated with 
mischievous organisms which resist a temperature of 155°, and 
which come from some special patron of the creamery. The 
mixed cream will not, therefore, serve as well for a starter as 
cream from some special patron that is delivered from a source 
that is free from such mischievous organisms. It has been 
learned that, in using Bacillus No. 41 in pasteurized cream, it 
is necessary to use a higher ripening temperature than when 
ordinary cream is used, in order to produce the proper flavor 
