98 PROFITABLE DAIRYING 



lactometer degree for each degree F. that the milk is 

 above 60 degrees, and subtract one-tenth for each degree 

 it is below 60 degrees. Having taken your lactometer 

 reading and having made the proper corrections of tem- 

 perature, determine the solids not fat and the total solids 

 by aid of the following formula: (It will be seen that 

 it is necessary that the per cent of fat in the milk be 

 known.) 



Solids not fat = % Lac. R. + .2 fat 

 Total solids = % Lac. R. -j- 1.2 fat . 



To illustrate: If the lactometer reading is 32.0 at 

 56° F., and the milk tests 4.0 per cent fat, we deter- 

 mine the solids not fat as follows : 



32.0 — .4 = 31.6 

 % of 31.6= 7.9 

 .2 of 4.00 = .8 

 7.9 + .8 = 8.7 = S. N. F. in sample. 



Having carefully studied the above, get several 

 samples of normal milk and determine the per cents 

 of solids and solids not fat in the same. 



Normal milk will have a lactometer reading vary- 

 ing from 29.0 to 33.0. 



XVII. To Determine the Effect of Skimming Milk on the 

 Lactometer Reading and on the Fat Content 



1. Determine the lactometer reading and the fat 

 content of a quantity of milk. 



2. Set aside two pint jars full of milk. 



3. Skim the cream from one of the jars after it has 

 stood for an hour. Take the lactometer reading and 

 the fat content of the milk. 



