CAROTIN, THE PRINCIPAL YELLOW PIGMENT OF MILK FAT 363 



holic petroleum ether. The proportion of xanthophyll to the entire pig- 

 ment in this test was very small, not over three or four per cent. 



The rose colored carotin solution showed three beautiful ab- 

 sorption bands, all of equal intensity. The measurements of the 

 bands were completely in accord with the standards given in Table 6. 

 The remainder of the carbon bisulphide extract of the dried car- 

 rot meal was evaporated into alcohol. The alcohol was diluted with 

 water to an eighty per cent solution and extracted with petroleum 

 ether (b. p. 3O-5o C) until no more color was extracted. The alco- 

 holic solution of the xanthophylls which remained was combined with 

 the solution of the xanthophylls washed out of the chromotogramm 

 with alcoholic petroleum ether. The combined solutions were evapor- 

 ated to dryness and the residue dissolved in a small amount of carbon 



bisulphide. This solution showed three 

 absorption bands and end absorption. The 

 measurements were the same as given in 

 Table No. 6. 



This carbon bisulphide solution was 

 orange colored when concentrated and 

 gave the chromotogramm shown in fig- 

 ure IV. There was a small amount of car- 

 otin pigment present which being unad- 

 sorbed was readily washed out and caught 

 at the lower end of the tube. Zone VIII 

 zone ii: Orange. was a i so on \y s iightly adsorbed and was 

 colorless. washed out by a stream of carbon bisul- 



- zone ni: orange, phide. When this zone was washed out 

 the suction was stopped. The CaCO 3 

 tinted zones were then removed separately 

 from the column with the aid of a knife; 

 5 2 was drawn off in each case at a 



Colorless. 



Zone I: Yellow. 



Colorless. 



colorless. 



Colorless. 



Zone V: ,* ^o 



Yellow-Orange, the Cb, 



zonevi* Green ^ ow tem P erature ? an ^ the pigment washed 



Colorless. 



/ Zone VII: 

 \ Red-Orange. 



Colorless. 



7 



f Zone VIII: 

 \ Faint Red 

 ( Orange. 



Rose. 



Cotton Plug. 



FIGURE IV. 



out with ninety-five per cent alcohol. 



Zone II was found to contain the 

 most pigment, judged from the color of 

 its alcoholic solution, with the lower zones 

 about the same with the exception of Zone 

 V which had very little pigment. Zone 

 I contained considerably more pigment 

 than was indicated by the color of its 

 zone in the chromotogramm. The spec- 

 troscopic properties of all the xanthophyll 

 constituents were studied with respect to 

 the normal xanthophyll bands. The results 



