STANDAEDIZATION OF CREAM. 257 



46. Problems in standardkation of milk and cream. 



1. When cream is too low in per cent of fat. 



Rule I. Subtract the per cent of fat in the cream 

 to be raised to a higher per cent from the desired 

 per cent. 



Rule II. Subtract the desired per cent of fat 

 from the per cent of fat in the cream to be used to 

 add to the cream; divide the first difference by the 

 second difference and multiply the quotient by the 

 number of pounds of thin cream to be raised to a 

 higher per cent of fat. The result is the number of 

 pounds of higher testing cream to be added to the 

 thin cream to be raised to a higher -per cent of fat. 

 The total cream would be obtained by adding the 

 number of pounds of rich cream to the number of 

 pounds of thin cream. 



Problem: 1,000 lbs. of 25 per cent testing cream 

 is to be raised to 40 per cent with cream testing 50 

 per cent butter fat. Find how many pounds of the 

 50 per cent cream must be added to the 25 per cent 

 cream to make it test 40 per cent. 



Solution: 40 per cent — 25 per cent=15 per cent. 

 15^-10=1.5. 50 per cent — 40 per cent=10 per cent. 

 1,000X1.5=1,500 lbs., the number of pounds of 50 

 per cent cream to be added to 25 per cent cream to 

 raise it to 40 per cent. 



One thousand pounds plus 1,500=2,500 pounds= 

 the whole amount of cream testing 40 per cent. 



Proof: 1,000 lbs. X 25 per cent=250 lbs. of butter 

 fat; 1,500 lbs. X50 per cent=750 lbs. of butter fat; 

 750 plus 250=1,000 lbs., total butter fat ; 2,500 lbs. 

 X40 per cent=l,000 lbs. 



