44. Report OF DEPARTMENT OF BACTERIOLOGY OF THE 
Duplicate bottles were prepared with milk containing 5 per 
ct. of fat, to which chloroform was added at the rate of 0.5, 0.8, 
1.0, 1.5 and 2.0 per ct.. The milk was held at 15.5° C. (60° F.). 
The germ content after various intervals is shown in Table VI. 
TaBLE VI.— GERMS PER CUBIC CENTIMETER IN CHLOROFORMED MILK CoN- 
TAINING 5 PER CT. OF Fart.* 



PERCENTAGE OF CHLOROFORM BY VOLUME, 


INTERVAL. 
0.5 0.8 ee 1.5 2.0 
Initjial germ) content | 77,200 
BrGITsk Vs yh ye ke Clee hae ee ee 95,700 | 97,200 | 44,700.} 17,300 680 
76,300 | 64,900 | 60,000 6, 600 2, £30 
Tee Te EDS CORRE EEE Ere han, (Fires Bee Too mal|ny 12,000 860 330 
to cou|nt 15,000 1,800 430 
UMS ap Yoh ote gle re Wen a a cn umin ye ate) Can Ih AE. 9g steed Too ma|ny 250 78 110 
to cou}nt 270 99 110 

a 
* Determinations made by Mr. Prucha. 
From this it is seen that while 1.0 per ct. of chloroform is 
sufficient to reduce the germ content gradually, so that curdling 
occurs only after the interval alloted for enzym action, 1.5 per 
ct. reduces the numbers to approximately the spore content within 
24 hours. 
It is interesting to observe that, in this test, the germicidal 
action with 1.5 per ct. is approximately equal to that observed 
with o.4 per ct. of chloroform in similar milk from which the 
fat had been skimmed. Thus the presence of 5 per ct. of fat 
neutralizes the germicidal action of about 1.0 per ct. of chloroform. 
In our study of the solubility of chloroform in milk it was 
shown that 1.0 per ct. of chloroform was required to saturate 
5 per ct. of fat. Accordingly, it would seem plain that the 
chloroform which is absorbed in the fat layer at the bottom of 
the milk is for all germicidal purposes removed from the milk. 
We frequently used chloroform in the study of enzyms in 
cheese where the fat content amounted to 20 to 30 per ct. Ac- 
cordingly two experiments were planned to determine the effect 
of 10 and 20 per ct. of fat upon the germicidal action of chloro- 
form. As they were in perfect accord, but one of them is here 
given. 
In order to obtain high percentages of fat, normal milk was 
enriched with fat in the form of melted butter, from which the 
casein had been removed by filtration, and the water and salt by 
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a ee 
