212 PRINCIPLES AND PRACTICE OF MILK HYGIENE 
scurvy developed in 28 per cent. of the children fed on 
milk which was pasteurized 24 hours after it was drawn 
from the cow by heating it at 158° F. (70° C.) for 30 
minutes, not a single case of the disease appeared in chil- 
dren receiving milk pasteurized immediately after being 
drawn from the cow, although it was from the same dairy 
and was pasteurized in the same manner. While many 
instances have been reported in which infants have been 
fed on pasteurized milk without harm, there appears to 
be no reason to doubt that milk loses some of its antiscor- 
butic properties in the process of pasteurization and that 
the age of the milk is also a factor in bringing about the 
change. 
The opinion prevails among medical practitioners 
that pasteurized or boiled milk is the cause of rickets 
and malnutrition, as well as scurvy, in children. The 
development of rickets under such circumstances has 
been attributed to the conversion of the soluble phos- 
phates of lime and magnesia contained in milk into an 
insoluble form by the action of the heat. Malnutrition 
is thought to result from pasteurized or boiled milk being 
less digestible than raw milk, a condition which is be- 
lieved to be due to the heat coagulating the proteids and 
rendering them less susceptible to the action of the diges- 
tive fluids. According to Rupp, however, heating milk 
at 145° F. (62.8° C.) for 30 minutes does not affect 
the soluble phosphates or the albumin. The coagulation 
of the albumin begins at 150° F. (65.6° C.) and increases 
with the temperature, but the soluble phosphates are not 
affected by temperatures up to 155° F. (68.3° C.). 
Feeding experiments with animals to determine the com- 
parative digestibility of raw and boiled milk have given 
contradictory results. While in most instances no dif- 
