94 STORRS AGRICULTURAL EXPERIMENT STATION. 
At the same time, there have been some improvements 
which have taken place in cheese manufacture as the result of 
bacteriological knowledge. It has been shown beyond perad- 
venture that a majority of the “ faults ” which arise in cheese 
and which make their appearance during ripening, are due 
to the growth in the cheese of certain malign kinds of bacteria, 
or sometimes due to the undue growth of bacteria which, 
under different conditions, would produce no injurious effect. 
The “ faults ” which arise in the cheese during the ripening are 
quite varied and need not be enumerated. They concern the 
appearance, the consistency, the taste, the odor, and the health- 
fulness of the cheese, and while it would be premature to say 
that they are all due to improper fermentations, it is now known 
beyond question that at least a majority of them may be attrib- 
uted to such causes. Moreover it is known that in many 
cases the sources of such troublesome fermentations lie in the 
fact that there has been used in the manufacture of the cheese, 
milk which has become unduly contaminated with malign 
bacteria. There have been enough instances discovered where 
a troublesome “fault” in the cheese has been traced to the 
milk from a single dairy to indicate that in the successful 
method of cheese-making of the future it will be necessary to 
have a more careful control over the kinds of milk used in the 
manufacture of cheese. , 
It has been suggested that perhaps it may be necessary to 
use the same process of pasteurization for the purpose of get- 
ting rid of such possible errors as is used in the butter manu- 
factories. The pasteurization of the milk for cheese-making 
has as yet, however, not been applied in any cheese factory. 
A few experiments have been made by bacteriologists to de- 
termine whether it is possible to pasteurize the milk without 
injury to its curdling powers under the influence of rennet. 
Of course, if such were not the fact, it would follow that pas- 
teurization could never be used with success in cheese-making. 
These tentative experiments have indicated that when the 
time comes that bacteriologists can offer promise of a great 
surety in the results, pasteurization of the milk for cheese- 
making is perfectly feasible, for when it is properly conducted 
the milk will be curdled by the rennet in a perfectly normal 
fashion. 
Almost the only practical application of bacteriology in 
general cheese-making which has been introduced as yet has 
been in the development and the application of a so-called 

