CAROTIN, THE PRINCIPAL YELLOW PIGMENT OF MILK FAT 353 



ether. Only a part of the residue would dissolve readily, and the 

 remainder only on addition of a little absolute alcohol. Eighty per cent 

 alcohol extracted a large part of the color from the alcoholic petroleum 

 ether solution. The portion which remained in the petroleum ether was 

 transferred to carbon bisulphide in which it showed three absorption 

 bands. (See Table 4.) The portion extracted by the eighty per 



cent alcohol was also transferred to car- 

 bon bisulphide. The latter solution showed 

 three absorption bands but the third was 

 faint and was not measured. (See Ta- 

 ble 4.) 



Alcoholic solutions of both portions 

 of pigment showed no color change on 

 the addition of a little concentrated HC1. 

 There was also no effect on the absorp- 

 tion bands. 



Zone i of the chromotogramm was of 

 a pure yellow color. It was completely 

 adsorbed by the CaCO 3 with respect to 

 CS 2 and was evidently the same pigment 

 which had been adsorbed in the first chro- 

 motogramm of the combined carotin and 

 xanthophyll-like pigments. A stream of 

 alcoholic petroleum ether readily washed 

 it out of the column as it did in the first 

 chromotogramm. In carbon bisulphide so- 

 lution the pigment had a light orange 

 color, and showed two brilliant absorp- 

 tion bands and a third fainter one. (See 

 Table 4.) 



The pigment showed the three bands 

 in alcoholic solution as well as in car- 

 bon bisulphide. When in alcohol, it gave 

 no color reaction with a little concentrated 



HC1, and there was also no immediate effect upon either the intensity 

 or position of the absorption bands. In the solid state this pigment 

 gave a transient greenish-blue color with concentrated H 2 SO 4 . 



Colorless. 



Zone I: 

 Yellow. 



Colorless. 



Zone II: 

 Orange, 

 shading 

 from light 

 to dark. 

 Zone III: 

 Deep 

 Orange. 



Colorless. 



Cotton Plug. 



FIGURE III. 



