Farm Dairying 251 



ness of cream separators is due to the action of centrif- 

 ugal force, which has a tendency to throw the heavier 

 particles to the outside. Cream being lighter than 

 skimmed milk, it is thrown to the center and the 

 skimmed milk thrown to the outside of a rapidly re- 

 volving hollow ball. 



358a. Farmer Smith milked ten cows, giving an average of 

 6,000 pounds of milk per year. He used the gravity creaming pro- 

 cess and lost one-third to three-fourths pound of butter on every 

 hundred pounds of milk due to imperfect separation of the cream. 

 His neighbor advised the purchase of a cream separator which 

 would leave only one-twentieth pound of butter-fat in the milk, 

 telling him that besides saving the difference in butter-fat he would 

 be able to feed his calves the fresh-skimmed warm milk. Estimate 

 the difference and give your advice to Farmer Smith. 



359. Sanitary Dairy Products. In the production 

 of sanitary dairy products great care must be observed 

 in the following particulars: (1) The healthfulness 

 of the animals. (2) The healthfulness of the milker. 

 (3) The cleanliness of the stables. (4) The care in 

 milking. (5) The care in keeping the milk. Unless 

 all of these conditions are carefully observed, sanitary 

 milk-production is an impossibility. 



360. The Healthfulness of the Animals. Unless the 

 the dairy cow is in a healthy condition, she should 

 not be expected to secrete a healthy milk. All of the 

 blood which goes to the manufacture of milk must pass 

 through the circulation, and if any diseases are present 

 the blood is apt to take up the germs producing them, 

 and in some cases these same germs have been found 

 in the milk. It will, therefore, be noted that the first 

 essential in the production of sanitary dairy products 

 is the presence of a healthy herd of cows. 



361. The Healthfulness of the Milkers. On account 



