MILK PRODUCTS 55 



its cream much more rapidly than other milk. This accounts for 

 the custom, with many farmers, of pouring a considerable amount 

 of cold water into their milk cans when they wish to secure cream 

 quickly for their own use. 



Separator Cream 



By the use of a separator, which consists of a rapidly whirling 

 steel bowl (5,000 revolutions, more or less, per minute), the heavier 

 portions of the milk — the skim milk and dirt — are thrown against 

 the inside of the rotating bowl by centrifugal force, while the lighter 

 portion — the cream — remains near the centre. The dirt sticks to 

 the side of the bowl, where it forms a tough, sticky layer known as 

 separator slime. This separator slime is not composed by any 

 means of filth entirely, because a good part of it is made up of the 

 proteid constituents of the milk (curd); one authority says that 

 nine-tenths of the dried slime is formed of this natural product 

 of the milk. That there is a great amount of filth in ordinary 

 market milk has been abundantly shown. It has been estimated 

 that the citizens of New York eat daily ten tons of barn filth and 

 refuse in their milk. This amount is probably exaggerated, since 

 Berlin is said to furnish its inhabitants but 300 pounds of cow 

 dung in its daily milk-supply, and, allowing a wide margin for our 

 native progressiveness, we could hardly be credited with beating 

 the Germans so tremendously in this international filth contest. In 

 the separator slime are to be found, in addition to the cheesy matter 

 from milk, manure, fodder, hairs, particles of skin, insects, down 

 from birds, threads from clothing, bits of bedding, cobwebs, bristles, 

 soil, etc., and large quantities of germs. The slime forms from 

 .04 to .3 of 1 per cent, of the weight of the new milk, depending 

 upon its original state of cleanliness.* The use of the separator is 

 superior to all other methods of obtaining cream on account of its 



* Separator slime should be burned to destroy tubercle bacilli in it. It should 

 never be used to feed swine. 



