MILK PRODUCTS 57 



Dr. Seibert states that by filtering milk through one-half inch 

 <of compressed cotton seven-eighths of the bacteria are removed. 

 This is a very slow process and some fat is removed by it. 



Complete separation of milk into cream and skim milk is some- 

 times done for cleansing purposes, the skim milk and cream being 

 reunited. Many physicians believe that milk thus treated is often 

 the cause of indigestion in infants. 



Neither these nor any other methods will make dirty milk clean. 



Contamination of milk begins at the farm, and only at the 

 farm can it be eradicated. Absolute cleanliness with respect to 

 milking and everything which comes in contact with the milk, 

 together with immediate cooling to below 50" F., will alone insure 

 success. The importance of germs in relation to milk is as great 

 as to the operating surgeon, and the amazing progress in both 

 surgery and dairying is due chiefly to the appreciation of this fact. 



Exclusive of fat, the percentage of the other constituents of 

 milk — proteids, sugar and mineral matters — is about the same in 

 cream as in milk, unless the cream be of unusual richness. For the 

 same reason, the composition of skim milk is about the same as 

 whole milk, the fat excepted. The fat is practically absent from 

 separator skim milk and is present in skim milk, from which the 

 cream has been removed by hand, to the extent of one-half to 

 one, or even one and one-half per . cent. The following tables 

 illustrate these statements : 



Composition Composition Composition Composition 



of milk of 20% Cream of 25% Cream of 67% Cream 



Per Cent. Per Cent. Per Cent. Per Cent. 



Fat 4-oo 20.00 25.00 67.00 



Sugar 4-5° 4-8 48 2.2 



Proteids 3-5 3-05 3-2 1.2 



Mineral matters . 0.7 0.6 0.7 0.1 



Composition of Composition of 



Hand-skimmed Milk Separator Skim Milk 



Per Cent. Per Cent. Per Cent- 



0.12 to 0.1 



Fat 0-75 (hand) (power) 



