290 MODERN BUTTER MAKING. 



which in this case is .018-|-.65, which equals .668. 

 This is the acidity of 112 lbs. of diluted cream. To 

 find the per cent of acidity we divide .668 by 112 

 which gives us .0059. .0059X100=.59%. Ans. 



Problems for Practice. 



Find the per cent of acidity in cream when: 



1. 10% water is added to cream having .75% 

 acid. Ans. (a) .68+%, (b) .69%. 



2. 15% water is added to cream having .80% 

 acid. Ans. (a) .695%, (b) .715%. 



3. 20% water is added to cream having .75% 

 acid. Ans. (a) .625%, (b) .65%. 



4. 10% water is added to cream having .65% 

 acid. Ans. (a) .59%, (b) .60%. 



5. 15% water is added to cream having .65% 

 acid. Ans. (a) .56%, (b) .58%. 



When milk with an acidity of .15% was used in- 

 stead of water in the above problems the answers 

 marked b show the result. 



72. Promiscuous problems. 



1. A creamery receives daily 1,500 lbs. of cream 

 testing 38% butter fat. The test is to be reduced to 

 30% by adding a skim milk starter, (a) How many 

 pounds of starter must be added? (b) What per 

 cent of starter is added? Ans. (a) 400 lbs., (b) 

 26 2/3%. 



2. The average test of 20,000 lbs. of hand sepa- 

 rator cream is 30%. After adding all the rinsings 

 the test is 29%%. The test for churning should be 



