CREAMERY PROBLEMS. 285 



B. Problems Pertaining to Cream Ripening. 



67. To find how many pounds of starter should 

 be added to cream of any richness to reduce it to 

 any desired per cent of butter fat, assuming that a 

 skim milk starter is used. 



Problem: How many pounds of starter will it re- 

 quire to reduce 3,000 lbs. of 30 per cent cream to 

 25 per cent cream? 



Rule. I. Multiply the cream pounds to be re- 

 duced by its test and divide the result by 100. The 

 result will be the total fat in the richer cream. 



II. Divide the total butter fat by the desired test 

 of cream and multiply the quotient by 100. From 

 this result subtract the cream pou.nds to be diluted. 

 The difference will be the amount of starter to be 

 added. 



Solution: 3,000X30-^100=900. lbs. butter fat; 

 (900h-25)X 100=3,600— 3,000=600 lbs. Ans. 



Explanation: By subtracting 25 from 30, we get 

 5 which is 1/5 of the test of the desired cream. The 

 same relation exists between the amount of cream 

 to be diluted and the amount of starter necessary to 

 dilute it. Therefore, it must be increased by 1/5 of 

 itself, or 600 lbs. of a skim milk starter. 



Problems for Practice. 



Find the amount of starter to be added to : 



Cream lbs. Cream test. Reduced to. Ans. 



