8o 



MILK AND ITS HYGIENIC RELATIONS 



In another case, after treatment with antiseptics, there was a 

 decrease of 0-362 per cent, of lactose in three years and five months. 



This work of Stocklasa's and Vandevelde's is open to the 

 objection that the milk was not obtained free from bacterial con- 

 tamination, but was only rendered sterile afterwards. The varieties 

 of bacteria which will ferment lactose are very numerous, and 

 it is, therefore, not unlikely that traces of ferment action might 

 occur in the solution in presence of the bacteria killed by means 

 of the antiseptics. 



The only value that lactase in milk could have for the infant, 

 must consist in the ferment acting with some rapidity upon the 

 lactose within the first few hours. For this purpose the twenty- 

 seven days of Vandevelde's experiment have no significance, espe- 

 cially in view of the very small amount of sugar decomposed. 



It was shown by Aders Plimmer (1906) that lactase is present 

 in the alimentary canal at birth, and in some animals just before 

 birth, in considerable amount, compared with which the strength 

 of ferment obtained in milk by Stocklasa and Vandevelde fades 

 into complete insignificance. Various authors have also detected 

 lactase in the alimentary canal of new-born infants. 1 Even if a 

 ferment of the strength found by these observers is present in 

 milk collected free from bacterial contamination, it is difficult 

 to believe that it could have any biological value whatever. For 

 this reason it will not be considered any further. 



The Second Group of ferments will now be considered. 



On the Presence of Oxidising Ferments in Milk. The presence 

 of an oxidising body in cows' milk was first mentioned by Klebs 

 (1868). In the work by subsequent observers the action now 

 known to be due to the ferment catalase appears to have been 

 confused with that of the ferment now known as peroxidase. 

 Babcock and Russell (i, 2) demonstrated the presence of the two 

 reactions, but believed that they were both manifestations of pro- 

 teolytic activity. These authors worked with a ferment solution 

 prepared by them from milk. The failure to differentiate between 

 these two reactions led to considerable confusion in the work of the 

 earlier observers. Raudnitz (i) in 1898 stated his belief that the 

 two reactions were due to separate bodies, and this was further 

 conclusively shown by Loew (i) (1901) and Neumann-Wender (i) in 

 1903. 



1 Cp. Ibrahim. 



