614 
The general practice of heating milk, which has now become a custom among 
the tenement population of New York, is undoubtedly a large factor in the 
lessened infant mortality during the hot months. 
Only the purest milk should be taken raw, especially in summer. 
No discussion of the subject is complete without recognition of the debt the 
world owes Mr. Nathan Straus for his early and persistent advocacy of pasteuri- 
zation and the establishment of his infants’ milk depots. Through his influ- 
ence and philanthropy this movement has now spread to many cities of this 
country and abroad. 
HOME PASTEURIZATION. 
If pasteurization is to be done perhaps the best place to do it is in 
the home, but the heating of milk to just 60° and the holding of it 
to just that temperature for twenty minutes, then cooling it rapidly, 
requires intelligence and careful manipulation. With the possible 
exception of infant feeding, it would perhaps be better and cheaper 
to pasteurize the milk in bulk under competent supervision instead 
of leaving it to the usual carelessness of cooks, who can not be ex- 
pected to master the technic nor appreciate the difficulties. Imperfect 
pasteurization may be worse than none, for it may result only in 
further contamination of the milk. 
Milk pasteurized in the home is commonly heated too high and not 
rapidly cooled. 
The most practical home pasteurizer is that devised by Freeman." 
The following experiments, made in the Hygiene Laboratory, with 
Freeman’s pasteurizer show its efficiency: 
Test No. A with Freeman's pasteurizer. 
Temperature of milk. 0° C. 
Temperature of water in jacket? 25° C. 
Milk introduced into boiling water and removed from the fire. 
Milk temperature — ° C. 
Five minutes after immersion in boiling water 47. 5 
Ten minutes after immersion in boiling water 63 
Fifteen minutes after immersion in boiling water 67. 4 
Twenty minutes after immersion in boiling water 68.8 
Twenty-five minutes after immersion in boiling water 68.9 
Twenty-eight minutes after immersion in boiling water 68. 9 
Whole time, twenty-eight minutes. 
Above 67° C. for thirteen minutes. 
Took fifteen minutes in running tap water at 22° C. to cool milk to 30° C. 
a Freeman, Rowland G. : Low temperature pasteurization of milk at about 
68° C. (155° F.). Arch, of ped., vol. — , 1896, p. — . 
