BERGAMOT. 435 



Vol. I., p 



Bergamot. The most important constituent of Bergamot oil, 

 amounting to 40 per cent., has (as mentioned in Vol. I., p. 77) 

 been found to he Linalyl-acdatc, (Linahjol-acetate), the acetic-ester 

 of Linalool, a liquid which is also contained in oil of lavender 

 (see above). This ester being the real vehicle of the bergamot 

 aroma, the quantitative estimation of it in a bergamot oil directly 

 indicates the value of the sample.* Messrs. Schimmel & Co. state 

 in a recent reportf their opinion of this method of evaluation, and 

 give the results of their experiments on various specimens of oil 

 as follows : — 



" Supported by the results of numerous observations, we 

 are now in a position to lay down exactly the requirements 

 for a genuine Bergamot oil. The value of a sample may he 

 accurately judged hy the deter mincdion of its pliysiccd properties 

 and the p)roportion of linalbol-acctcde ichieh it contains. 



" The chief adulterants of Bergamot are oil of turpentine, oil of 

 orange and oil of lemon. :|: All three aftect the solubility of the 

 Bergamot oil in diluted alcohol, and reduce its specific gravity and 

 the percentage of ester. In examining Bergamot oil it is therefore 

 first of all necessary to ascertain the specific gravity and specific 

 rotatory power. It should he sohdjle at 20° C. in IJ to 2 volumes 

 80 p)^^ c^'^d. alcohol ; slight turbidity, which becomes greater upon 

 the addition of more alcohol, is caused by the separation of 

 Bergaptene, hid no smcdl drops of oil should remain undissolved. 



" To distil the oil under ordinary atmospheric pressure, is quite 

 useless for the purpose of determining the value, as under such 

 conditions a radical decomposition of the oil supervenes. 



" The following tables contain, besides physical data, the results 

 obtained in an ester-determination of Bergamot oils of different 

 quality : — 



* Compare the researches of Semmlerand Tiemann, Ber. Deutsche. Chem. 

 Ges., XXV., p. 1180. 



t Btricht., April, 1893. 



:J: For other adulterants see p. 76, vol. i. 



