VANILLIN 



133 



Constituents. An odorous crystalline principle, vanillin, from 



1.5 to 3 per cent; an odorous, balsamic or resinous principle, which 



is developed during the process of curing and to which the peculiar 



odor of vanilla is due; sugar about 10 per cent; fixed oil about 10 



per cent; calcium oxalate in raphides; ash about 5 per cent. 



Vanillin or methyl-protocatechuic aldehyde is manufactured on a 

 large scale from eugenol or coniferin. It occurs in white, acicular 

 crystals (Figs. 57 and 58), which are sparingly soluble in water, sol- 

 uble in alcohol and glycerin, the solutions being colored blue with 

 ferric chloride. Vanillin may be formed as a result of certain oxida- 



FIG. 57. Vanillin, orthorhombic crystals obtained from saturated aqueous 



solutions. 



tion changes rather than through the action of a ferment-like emulsion 

 which, as has been recently shown, does not exist in the fresh pods. 



The fruits of a number of species of Vanilla yield vanillin, which is 

 also found in the Orchid, Selenipedium Chica, of Panama; the fruit 

 of Rosa canina, of Northern and Middle Europe; the flowers of 

 Spireae Ulmaria; the balsams and resins of the genus Toluifera; in 

 the seeds of Lupinus albus, of Europe, which is cultivated; and in the 

 bulbs of Dahlia. 



Commercial Varieties. In addition to the Mexican and Bourbon 

 beans, other varieties are found in the market. Mauritius Vanilla 



