108 MANUlr-eiMENERAL AGEICULTURE. 



L being the lactometer reading at 60F or corrected 

 for temperature, and f the per cent of fat in the milk. 



Example. If the lactometer reading (L) is 31.2, 

 the temperature (T) is 64 and the per cent of fat (f) 

 is 3.6 the calculation of Solids not fat is as follows: 

 31.2+.4=31.6, the corrected lactometer reading, adding 

 .1 for every degree over 60. 



Per cent of solids not fat= : V4L+.2f, 



=%x31.6+.2x3.6 

 =7.9+. 72=8.62% 

 Per cent total solids =%L+1.2f, 



=7.9+4.32=12.22% 



Or for per cent of total solids simply add the fat 

 to the solids not fat as 8.62+3.6=12.22. 



81. TEST FOR PHYSICAL ADULTERATION 

 OF MILK. 



Materials: Lacometer, Babcock tester, normal, 

 watered, skimmed, and watered-and-skimmed milk. 



Milk may be adulterated by being watered, skimmed, 

 or both watered and skimmed. 



If the analysis of the suspected sample shows 

 sp. gr. of milk ....................................... ) J QW } 



fat and solids not fat ....... . ....... - f [ watered 



sp. gr. of solids ....................... ...... normal ) 



sp. gr. of milk and of solids.... j. . ) 



solids not fat ................. ..................... f hl h V skimmed 



fat and, solids ............. .. ........................ low ) 



sp. gr. of milk ....................................... normal } watered 



sp. gr. of solids ................................. normal or high > and 



fat and solids not fat .................. low ) skimmed 



Latitude of variation. 



Specific gravity of milk may vary from 1.029 to 1.035. 

 Fat must not fall below 3. 



Solids not fat must not fall below 9. (in most states.) 

 Specific gravity of solids may vary between 1.25 and 

 1.34. 



