THE TESTING OF MILK AND CREAM 139 



especially noted : Board of health readings can never be used 

 in these formulae, consequently B. of H. readings must be changed 

 to Q. ; specific gravity readings cannot be used ; the percent- 

 age of fat expressed in hundredths cannot be used. 



An illustrative example will show how these formulae operate. 

 Suppose the Q. lactometer reading of a sample of milk was 32.5 

 at 60 F. and the fat reading was 4.2 per cent, what are the solids 

 not fat ? 



Formula 1 = 



L-f .71 



= S. N. F. .7 X 4.2 = 2.94 



3.8 



2.94 + 32.5 = 35.44 

 35.44 H- 3.8 = 9.32+ 



Formulating the above calculation : 

 32.5+2.94 



^ 



9.32 + 4.2 = 13.52 total solids 

 Using formula 2 : 



t + 1-S.N.P. ' 



4 



32.5 + 4.2 = 36.7 

 36.7 + 4 9.17+ % S. N. F. 



Formulating the above calculation : 



4 

 9.17 + 4.2 = 13.37 T. S. 



