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THh; FKEKZING POINT OK MILK. 



The folJowing references to work clone on the freezing 

 point of milk are worth noting : — 



Dr. Barthel (" Methods used in the Examination of 

 Milk and Dairy Products, 1910 ") refers to the freezing 

 point of milk as follows : — 



" This method of determining the amount of added 

 water is very simple and perfectly reliable if carried out 

 oarefuUy. It is remarkable that it has not found more 

 general application, for it not only shows that water has 

 been added, })ut gives also the amount with accuracy. 

 The author has experimented with this method and is 

 quite satisfied that the results are reliable, and that in agree- 

 ment with Winter and Parmentier, 8chnorf, and others, 

 pure unadulterated milk never has a higher freezing point 

 than — 0-54^ C. This is independent of breed, individuality, 

 sexual excitement, the amount of fat, etc., but a very small 

 addition of water at once raises the freezing point." 



J. Cornalba (" On the Milks of Lombardy, Chemiker 

 Zeitung, 1907-1909 ") shows the const«ancy of the freezing 

 point to fall between —0-55° C. and —0-56° O. He also 

 points out that colostrum with salts ranging between 0-9 per 

 cent, and 1*12 per cent, gave normal freezing points. 



J. Winter and E. Parmentier obtained from single 

 cows freezing points varying from —0*54° C. to —0*57° C. 

 The mixed milk from a herd never I'ose above - 0-.55° C. 

 or fell below -0-56° C. 



P. Ducross and H. Imbert (Bull. Sciences Pharmacal, 

 1905) obtained a value of —0-533° C. from a sick cow and 

 a sample of milk from a cow in calf gave a freezing point 

 of -0-535^ (J. 



Beckmann & Jordis (Forschungs berichte uber Lebens- 

 mittel, 1895, Vol. II.) found the average freezing point 

 to be -0-554° C. 



It seems that for the mixed milk of a herd there is 

 variation between only —0-55° C. and —0*56° C, but for 

 milk from single cows in a diseased or abnormal state 

 wider variations may occur. 



i The freezing point method places us in a sound position 

 as r^ards the milk control. In the past, on the old standard 

 an honest milk vendor was liable to be prosecuted for 



