COMMERCIAL TESTING OF MILK AND CREAM 243 



and (5) appearance. For all practical purposes color 

 and package can be omitted. In educational competi- 

 tions they may be included. 



Composition. By composition is meant the per 

 cent, of fat and of solids-not-fat in milk. The com- 

 position of milk, other things being equal, is the direct 

 and only practicable measure of value as food, and 

 this must constitute an important factor in judging 

 the value of market milk. 



Testing composition. The percentages of fat and 

 of solids-not-fat are found in the manner described 

 on p. 57 and p. 185. 



Terms' describing composition. Only two terms 

 need to be used in describing the composition of milk : 

 (i) perfect and (2) defective. 



(1) Perfect, as applied to testing and scoring milk, 

 means milk containing not less than 4 per cent, of fat 

 and not less than 9 per cent, of solids-not-fat. 



(2) Defective applies to milk containing less fat 

 or solids-not-fat than required for milk of "perfect" 

 composition. 



The figures selected to indicate milk "perfect" in 

 composition represent as nearly as possible normal 

 milk of average composition. Injustice would obvi- 

 ously be done by selecting 4.5 or 5 per cent, as the 

 amount of fat to represent milk perfect in compo- 

 sition. It would, on the other hand, be very unsatis- 

 factory to take a so-called legal standard as repre- 

 senting perfect composition, because it is not a stand- 

 ard at all but simply a method of prescribing the low- 

 est permissible amounts of fat and solids that will be 

 legally tolerated in milk. 



