WISCONSIN WORK IN COLD CURING. 13 
ies, and the development of the cold-storage system did away with 
any necessity for a cool factory curing room. 
Following the introduction of cold-storage curing, cheese was held 
in the factory for a much shorter period than formerly. The subearth 
duct was expensive, and well-insulated curing rooms were found to be 
sat isf actor}" for the shorter period before going to the storage room. 
THE WISCONSIN WORK IN COLD CURING. 
The work in Wisconsin, already mentioned, led Doctors Babcock 
and Russell to believe that the processes through which cheese passed 
in curing were due partially at least to other agencies than bacteria. 
Investigations were conducted which led to the discovery of galac- 
tase, a an enzyme natural to milk and which has the power of breaking 
down the casein. It is not the purpose of this bulletin to enter into 
any details of that discovery or of the controversy that has resulted 
between scientists on this general subject of cheese curing. This dis- 
covery indicated that it might be entirely possible to cure cheese at a 
much lower temperature than had previously been used, and naturally 
led to experiments along this line. There is no doubt that this dis- 
covery has been responsible for many changes in the cheese industry, 
for it has affected the curing processes, has indirectly modified the 
taste of the consumer, and a long series of changes has followed, soiue 
of which are still in progress. 
The Wisconsin Station was the first to inaugurate experiments in the 
cold curing of cheese. 6 This very naturally followed the discovery of 
galactose and the previous experiments in cool curing, which might be 
considered as preliminary to the greater work that followed. Wiscon- 
sin's first work along these lines was followed in a short time by similar 
experiments at Guelph, Ontario, Canada, under the direction of Pro- 
fessor Dean, head of the dairy department of the Agricultural College. 
About an equal amount of work has been done by these two institu- 
tions, but of course that done by Wisconsin will always be of the greater 
interest, because to this station belongs the credit of having made the 
discovery which naturally led up to this work, and because of its gen- 
eral activity along these lines. 
THE FIRST COLD-CURING EXPERIMENTS. 
The first actual cold-curing experiments were undertaken at the 
Wisconsin Station following the discovery of galactase. c In these 
tests five temperatures were employed, 15°, 33°, 40°, 50°, and 60° F. 
a Annual Report, Wisconsin Experiment Station, 1897. 
b " Cold curing " is the term ordinarily applied to curing at temperatures below 50° F., 
to differentiate it from the method employed in Canada, where artificial temperatures 
above 50° F. are used and the process is termed " cool curing." These terms are well 
understood by cheese men and are entirely distinct. 
c Annual Report, Wisconsin Experiment Station, 1901. 
