158 Bulletin of Lab orator ies of Denison Ufiiversity voi. xj] 
them down in his product is still a question. That he frequent" 
ly fails to prevent their development, much of our product bears 
a sad testimony. That the gas producing germs are largely 
associated with filth and general uncleanliness in the dairy, 
is quite well established. This enables us to apply a ready and 
all desirable remedy, namely, to remove all traces of filth in all 
stages of the work. “The Wisconsin curd test gives still 
other means of combatting this evil, for by it the sources of the 
infection can be readily traced. 
Apparently the casein digesters may be at times quite 
harmless, but many of them induce fermentations resulting in 
bitter by-products which are very undesirable and undoubtedly 
prevent the product from reaching the highest grade, if indeed, 
it is not ruined by them. A more detailed study of the vari- 
ous germs of this class is necessary before we can ascribe to 
them their due importance in the manufacture of cheese. 
However, we have still to explain the presence of the acid 
germs in such enormous numbers. It is quite certain that they 
are not concerned, at least to any great extent, in the changing 
of the indigestible casein into the digestible products. Their 
function as acid producers is no doubt important in communi- 
cating to the ripened product that peculiar flavor, so indescriba- 
ble but so highly desirable, and which lends to cheddar cheese 
its own peculiar qualities. If this is true, these germs should be 
found in all cheddar cheese, no matter in what section of the 
country it is made. So far our investigations were largely lim- 
ited to cheese made at the Wisconsin Dairy School. We now di- 
rected our study to the state at large and finally to other states, 
to determine the presence of these germs and at the same time 
to make as detailed a study of the cheese flora as possible. The 
results of these investigations so far as they related to cheddar 
cheese are tabulated below : 
^Babcock, Russell and Decker, — Factory tests for milk. Bui. 67, Wis. 
Agrl. Exp. Station. 
