BOILED MILK OF THE SAME SPECIES 163 



markedly inferior gain in weight upon the boiled human milk, 

 to that which they exhibited upon the breast milk. 

 ' The average gain in weight noted was as follows : 



In case I : 



In fourteen days on the breast the average gain was 26J 



grammes per day. 

 In eight days on the bottle with raw human milk the 



average gain was 37 grammes per day. 

 In ten days on boiled human milk the figure was 9-9 grammes 



per day. 



In case II : 



In seven days the average gain on the breast was 14 grammes 



per day. 

 In five days on raw human milk in a bottle it was 20 grammes 



per day. 

 In seven days on boiled human milk it was 9 grammes 



per day. 



It would be unwise to base any assertions upon two experiments, 

 but as far as the experiments go, it would appear that some of the 

 value of the human milk is lost by boiling. It is curious that both 

 children showed a greatly increased average gain per day, when 

 fed upon the human milk in a bottle as compared with the breast, 

 and this rather suggests that they were getting more actual food in 

 the shape of a larger quantity of milk. It might be that different 

 results would have been obtained if the milk had not been boiled for 

 as long a time as ten minutes. Moro attributes the effect pro- 

 duced to a loss of the so-called ' protective substances ' of the milk. 



L. F. Meyer (1906), in the course of his ' Exchange ' experiments, 

 where three children were fed first upon human whey and the protein 

 of cows' milk, and then upon cows' milk and the protein of human 

 milk, found that if the human whey was boiled the good results 

 obtained with the first mode of feeding were greatly reduced. 

 As, however, the experiment was only carried out over a very 

 few days, and was an isolated one, it cannot be taken as proving 

 that substances necessary for health are lost by the boiling of milk. 



It would appear also that Meyer himself does not lay much 

 stress upon this experiment, since in his book (1910) in conjunction 

 with Langstein he says, ' clinical observations could not show any 

 advantage of raw cows' milk over boiled, and recent experiments 

 have also shown that the boiling of human milk does not cause 

 any deterioration of its nutritive value.' 



Potpeschnig (1907) carried out some work with a view to ascer- 

 taining whether these same hypothetical substances said to have 

 a protective function were injured by heating to 60 C., this being 

 the temperature to which v. Behring considered that milk might 

 safely be heated without undergoing any loss of nutritive value. 



M 2 



