471 
Table Xo. 22. — Milk from healthy cow (No. 2) inoculated 1\ hours after milking. 
[24-hour agar culture in each case.] 
B. typhosus in whole raw milk 
B. typhosus in whole milk heated to 60° C. 30 minutes 
B. typhosus in whole milk heated to 70° C. 30 minutes 
B. typhosus in whole milk first frozen for 48 hours 
B. typhosus in milk boiled for 1 minute (control) 
B. lactis aerogenes in whole raw milk 
B. lactis aerogenes in whole milk heated to 60° C. 30 minutes 
B. lactic aerogenes in whole milk heated to 70° C. 30 minutes 
B. lactis aerogenes in whole milk first frozen 48 hours 
B. lactis aerogenes in whole milk boiled for 1 minute (control) 
Original milk 
Bacteria 
per loop at 
once after 
inocula- 
tion. 
Colonies per loop after 
10 hours at 37° C. 
Shaken. 
! Vigorously 
agitated.' 
1,000 
3,500 
19,500 
1,700 
18,000 
43,000 
2,100 
“ b 200, 000 ; 
a b 300, 000 
1,520 
1,020 1 
1,800 
ab 400. 000 
2,000 
29,000 
75,000 
1,670 
aXlOO 
“X100 
870 
°xioo 
“X200 
1,040 
“X 20 
3,000 
«X 30 
13 
210 
“Innumerable. 
b About. 
X Means about the stated number of times the number of colonies shown in the first column. 
REVIEW OF THE LITERATURE UPON THE SUBJECT. 
It will be seen from the following review of the literature upon 
this subject, that our work confirms the facts which have been recorded 
by some others. There is, however, a disagreement concerning* the 
interpretation of these facts. One class of observers, while admit- 
ting that there is a primary reduction of bacteria in fresh raw milk, 
believes this to be entirely independent of any germicidal action of 
that fluid. The reduction is attributed to other causes, such as a 
“restraining” action of the milk, inhibition resulting from strange 
media, etc. Others believe that fresh raw milk possesses definite, 
though feeble, germicidal properties. Some of the authorities cited 
absolutely deny not only the germicidal but the restraining power of 
milk, claiming a steady increase in numbers from the start. 
Fokker a was the first to call attention to the bactericidal prop- 
erties of milk. He was led to investigate this subject through the 
results of Nuttall, Buchner, and Lubarsch, who found that blood 
contained substances capable of destroying bacteria. Fokker 
obtained goats’ milk under careful aseptic precautions and divided 
it into two portions, one of which was heated, and both portions 
then infected with bacteria of souring milk. The cooked portion 
would always sour within twenty-four hours, while the fresh, un- 
heeded portion would keep at least, and sometimes more than, three 
or four days. 
a Fokker, A. P.: Ueber die bacterienvernichtenden Eigenschaften der Milch. 
Fortschr. der Med., vol. 8, 1890, p. 7. 
/ 
