129 



II. 



CHEMICAL ANALYSIS OF BUTTER FAT. 



Since butter fat represents complex mixtures of glj-cerides of the different 

 fatty acids, complete fat analysis should embrace the separation of each fatty 

 acid ciuantitativel}'. An attempt to detect and identify the individual fatty 

 acids, in a way as is done in inorganic chemistry in determining individual 

 elements, must be abandoned as a hopeless undertaking in fat anah-sis. How- 

 ever, in fat analysis the results obtained are not accurate in strict scientific 

 language, they are relative rather than absolute. Methods have been worked 

 out which answer all technical purpose. These methods consist in obtaining 

 certain "values" or numbers. These numbers are characteristic of the fats 

 depending on the nature and properties of the fatty acids. 



These "numbers" or "values" have been termed quantitative reactions. 

 When the methods are strictly followed, uniform results are obtained, and 

 for that reason the "number" or "values" are called "constants," specific 

 for each kind of fat. The "constants" in fat analvsis are divided into 



Physical 



j Solidifying point, 

 j Melting Point, 



Refractive index, 



Sp. gravity. 



Chemical 



Reichert-Meissl 



Saponification 



Iodine 



Hener 



Thermal or 



Maumenc 



value, 

 value, 

 value, 

 value. 



value. 



III. 



THE RELATION OF BUTTER FAT CONSTANTS AND CALCULATED DATA FROM THE 

 CHEMICAL ANALYSIS. 



In chemical analysis of butter fat it is often desirable to obtain data of 

 relations other than the relations obtained directly by the determination of 

 the chemical constants. From these data we are able to account and inter- 

 pret some of the variation in the physical constants, where, owing to the 

 complexity of the glycerides the chemical constants do not indicate in them- 

 selves the variation of the physical properties. 

 9—33213 



