338 



CREAM SEPARATION 



If one wishes to know, for example, how much 42 per cent 

 cream should be added to 10 pounds of skim milk to make a 

 20 per cent cream, one figures as before. 22 : 20 : : 10 : x. This 

 gives 0.09 pounds, as may be proven thus: 



.42 X 9.09= 3.82 

 00 X 10 = 0.00 



19.09 ) 3.820 ( .20 per cent of fat 

 3.818 



20 

 Example 3. — Given milks carrying •> Vi* an d 5 per cent fat 

 to be mixed to make 4 per cent milk : 



(5 — 4 = 1) 



(4 — 3i/o 



i/o : 1 : : 1 : 2. Hence one can of the lower and two of the 

 higher grade will make three cans of the 4 per cent grade. 

 Any other figures may be used as desired ; as, for example, 



4.6 and 3.3 to make a 3.7 per cent grade. 4.G — 3.7 = 0.9 



3.7 — 3.3 = 0.4. Four parts of the higher grade and nine 

 parts of the lower are called for. 



This method of finding out how much of any two substances 

 will be required to produce any desired blend may be applied 

 to anything and everything wet or dry just so long as they 

 are combined by weight, or have the same weight per unit 

 of measure. 



Another very convenient tool in this connection is a rule by 

 means of which one may find directly how many gallons (or 

 pounds) of rich cream and skim milk will be required to pro- 

 duce any definite number of gallons (or pounds) of cream test- 

 ing any definite percentage of fat. The rule is : Multiply the 

 amount of cream desired by the test of the cream desired and 

 divide this product by the test of the rich cream at hand. This 



