124 



Condensed Milk and Milk Powder 



certain seasons of the year, to incorporate more than 24 per cent, 

 solids without injuring or destroying the marketable properties of 

 the product 1 . 



Butterfat. — The fat varies with the per cent, of fat in the 

 fresh milk and with the degree of concentration. No fat is lost dur- 

 ing the process of condensing and sterilizing. 2 It has been claimed 

 by some that in the process of manufacture, the volatile fatty acids 

 escape and that the evaporated milk therefore contains less fat than 

 the fresh milk from which it is made, times the degree of concen- 

 tration. If this were true the loss of fat in the evaporated milk 

 would not exceed .25 of 1 per cent. But analyses show that the fat 

 in the evaporated milk is entirely normal in composition and con- 

 tains the same proportion of volatile fatty acids as the fat in the 

 fresh milk. 



In the evaporated milk there is a strong tendency for the fat to 

 separate out during storage and to churn in transportation. This is 

 largely avoided by the proper adjustment of the sterilizing process 

 and by use of the homogenizer. 



Proteids. — The proteids vary with the per cent, of total pro- 

 teids in the fresh milk and the degree of concentration. Similar to 

 the case of sweetened condensed milk there is a tendency of a slight 

 loss of proteids in evaporated milk due to mechanical adhesion of 

 a part of the precipitated curd to the heating surfaces in the fore- 

 warmers and in the vacuum pan. 



Most of the coagulable milk albumin is precipitated. Fresh 

 milk contains about .16 per cent, of albumin that is not coagulable 

 by heat. 3 The relation of soluble and insoluble curd is shown in the 

 following table which represents analyses of different brands of 

 evaporated milk. 



1 Hunziker, Indiana Agricultural Experiment Station, Twenty-first Annual Report, 190S 

 pages 67-68 



2 Hunziker and Spitzer, Indiana Agricultural Experiment Station, Bul'etin No 134 

 8 Hunkizer, Indiana Agricultural Experiment Station, Bulletin No. 143 



