104 REPORT OF DEPARTMENT OF BACTERIOLOGY OF THE 
COMBINED FLORA OF THE NINE CHEESES. 
QUANTITATIVE SUMMARY. 
For the reasons already given quantitative results on the germ 
content of the milk and whey are available for only three cheeses, 
the study of the germ content of the other cheeses beginning after 
two to eight days. 
At the time of beginning the process of manufacture the germ 
content of the milk for Cheeses 4.6 VIII, IX and X was 9, 9, and 
47 millions per cc. respectively. From the time the milk is put into 
the vat until the cheese is ready for the press a temperature favor- 
able to germ life is maintained. During the first hour the germ 
content rose in the milk for Cheese 4.6 VIII to 16 millions and in 
that for IX to 29 millions per cc. 
The addition of rennet separates the milk into whey and curd. 
In Cheese 4.6 VIII while the milk contained 16 millions per cc. 
when the rennet was added, the whey showed only 10 millions per 
cc. after the lapse of two hours. In Cheese 4.6 IX two hours after 
adding the rennet the germ content of the whey was 5 millions per 
cc. higher than that observed in the milk. In Cheese 4.6 X when 
the curd was first cut the whey contained 26 millions per cc. less 
tnan were found in the milk one and one-half hour previous. 
Within the following hour and a half the whey increased 20 mil- 
lions per cc. leaving it only 4 millions lower in germ content than the 
original milk. It would seem a fair deduction from these data that 
in the process of coagulation a large proportion of the germs in the 
milk are caught in the curd, but that the favorable growth condi- 
tions in the whey leads to a rapid multiplication in that fluid. 
In studying the flora of the curd the gram is taken as the unit of 
measurement. At first the specific gravity of the curd does not 
differ markedly from that of the whey but with the continued expul- 
sion of the moisture it increases to about 1.5. Exact data on these 
changes are lacking. In order to make comparisons of the quanti- 
tative results in milk, whey and curd, the numbers per gram found 
in the curd should be multiplied by a factor not larger than one and 
one-half. Our data indicate that as the whey is expelled from the 
coagulated mass it does not contain its volumetric proportion of the 
germs previously found in the milk. Unfortunately we have no ob- 
servations on the germ content of the freshly coagulated curd but 
observations made upon the ripened curd just previous to adding 
