258 DAIRYING. 



CALCULATION OF TOTAL SOLIDS OP MILK. 



The relation existing between the various components of 

 the milk is such as to make possible the calculation of the 

 percentage of solids not fat, and total solids, in a sample of 

 milk when the fat-content and the specific gravity (lactom- 

 eter reading) of the milk are known. Several formulas 

 have been worked out by chemists in different parts of the 

 world, by the application of which the total solids may be 

 calculated from the percentage of fat and the specific grav- 

 ity of the milk. We give here Babcock's formula, pub- 

 lished in the twelfth report of Wisconsin Experiment 

 Station. 



(lOOs — sf \ 

 ^ — i| X (loo — /) 2.5, 

 100 — I.0753J/ / ^ y / -" 



where s = specific gravity of the milk and/ per cent of fat 



found. When s and /"are known the per cent of solids not 



fat in the milk may be calculated by means of this formula. 



ill order to avoid making the lengthy calculations in every 



case, tables for solids not fat are given on the following 



pages; results obtained by the formula given above, or 



by means of the ft)llowing tables, will come within a couple 



of tenths from the actual percentages present, when 



reasonable care is taken in the determinations of fat and 



specific gravity (or lactometer reading). 



Short formulas . The following formulas for solids not 



fat and for total solids are derived from the data given in 



the following tables. L = lactometer reading at 60^ F. 



(specific gravity X 1000— 1000); /* = per cent of fat in 



milk. 



Solids not fat = \- .if 



4 



Total solids = — h 1.2/. 

 4 



