CREAMERY BY-PRODUCTS 329 



Fifteen to sixteen pounds of cottage cheese are ob- 

 tained from one hundred pounds of skim-milk, and the 

 cheese retails at from five to fifteen cents per pound. 



SkimmiIk=Buttermilk. To ordinary skim-milk add 

 from 20 to 25% starter and sour at a temperature of from 

 65 to 70° F. When thoroughly curdled, churn the same 

 as cream. Fifteen minutes churning is usually sufficient. 

 Next cool to 45° F. or below and strain. Soda fountains 

 prefer this skimmilk-buttermilk to ordinary buttermilk, 

 being of better flavor and heavier consistency. The less 

 the skim-milk is churned the heavier the consistency. 



Skim-milk containing about one per cent of fat makes 

 a more palatable buttermilk than pure skim-milk and 

 retails at from five to ten cents per quart. 



Commercial Casein Making. In some sections where 

 the creameries receive much whole milk, a great deal of 

 the skim-milk is converted into casein which nets the 

 farmers approximately twenty cents per hundred pounds 

 of skim-milk. The process of manufacturing casein is 

 essentially as follows: 



Place the skim-milk in a vat and heat it to a tempera-* 

 ture of from 120 to 130° Fahrenheit; then add at the rate 

 of about one pint of commercial sulphuric acid per thou- 

 sand pounds of skim-milk. Thoroughly mix and in a 

 short time the whole mass is coagulated. As soon as thor- 

 oughly curdled, the whey is drawn off, the curd placed 

 in a strong, heavy cloth and then pressed. Usually an 

 upright press is used in which the curd remains over 

 night. The next morning the pressed curd is ground up 

 fine and spread upon trays which are piled about twenty 

 deep on special trucks which, in turn, are run into a 

 dryer about four feet high, three feet wide and twenty 



