212 PRINCIPLES AND PRACTICE OF MILK HYGIENE 



scurvy developed in 23 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 Hupp, 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- 



