154 SCIENCE AND PRACTICE OF DAIRYING. 



the residue forms '05 to 13 per cent of the weight of the separated 

 milk. The loss of nitrogenous matter which the milk suffers in the 

 process of separation is inconsiderable, as it only consists of from 

 *5 to '8 per cent of its entire amount. This loss is of such a kind, 

 however, that the formula devised by the author for the calculation 

 of the dry substance of milk from its specific gravity and its percentage 

 of fat is not applicable to skim-milk obtained from the separator. 



Investigations, carried out at different times at Baden, showed that the 

 fresh separator residues had, on an average, the following composition : 



Water, 67'3 



Fat, 1-1 



Caseous matter, 25'9 



Other organic constituents, 21 



Ash, 3'6 



100-00 



Two analyses made at different times showed the composition of the ash 

 of the separator residue to be, on an average, as follows : 



Potash, 



Soda, 



Lime. 



Sesquioxide of iron, ... 

 Phosphoric anhydride, 

 Chlorine, 



100-381 

 Deduct oxygen replaced by chlorine, ... "381 



100-000 



80. Cream. If the numbers indicating the weight of the cream 

 and the skim-milk, after the separation of the milk, be added to- 

 gether, it will be found that the sum of the two is never equal to 

 the number representing the weight of the milk, since losses occur 

 through the evaporation of water, the clinging of water to the sides 

 of the vessels, and unavoidably in the pouring of the milk from one 

 vessel to another. Where separation is carried on carefully, these 

 losses in large separating dairies should not exceed *5 to "75 per cent 

 of the weight of the milk. Investigations carried out on the older 

 creaming methods, on cream and skim-milk, showed that if water 

 were allowed to evaporate from the milk during creaming, a distinct 

 increase in the proportion of protein occurred, with a diminution 



