94 



MASS. EXPERIMENT STATION BULLETIN 166, 



Transparency or opacity (0.5 



inch cell). 

 Fluorescence or bloom, 



Odor (cold and hot), . 

 Taste, 



Mineral oils, seldom in fatty oils. 



Characteristic of product (fatty acids, amines, etc.). 



Rancidity. 



(Characteristic of product. 

 Finest (first quality), "hard," "harsh." 

 Rancidity. 



Specific gravity, 



Melting point, . 

 Solidifying point, 



Refractive index, 



Optical rotation, 



Colorimeter, 

 Viscosity, 



Solubility, 



Flash point. 

 Ignition point, . 



Physical Tests 

 t 



t = 20°, 40° and 60° C. 



d 



1 4°C. 



I Coefficient of expansion. 



° C. (lower in mixed than in simple glycerides) . 



°C. 



j Abbe refractometer, n — 

 \ D 



t = 20°, 40° and 60° C. 



Dispersion. 



Dextro rotatory, 200 m.m. tube. 



Lsevo rotatory. 



Lovibond tintometer, 0.5 inch cell. 



Redwood viscosinieter, 70° Fahr. 



Crismer, critical temperature of dissolution, ° C. 



Valenta test, ° C. 



°C. 



°C. 



Synopsis of Composition — Oils and Fats. 



' The odor of fish oils is said to be due largely to clupanodonic and homologous acids. 



' Nominally a part of the neutral fat, but differentiated to facilitate subsequent calculations. 



• Occur as free alcohols and, to some extent, in combination with fatty acids, as esters. 



