Scientific and other notes on essential oils. 17 



The bad quality of this product was betrayed by the too great difference between 

 the saponification value and acid value II (normally not above 10), as well as by the 

 much too great a residue on evaporation (normally 4.5 to 6 per cent.), which besides 

 apparently consisted only of a fatty oil and probably contained none of those wax- 

 like components which are so characteristic for bergamot oil. As fatty oils have a 

 high saponification value, it has evidently been added with the object of leading to 

 assume the presence of a bergamot oil rich in linalyl acetate, as the above-mentioned 

 ester value would lead to the assumption of about 38.5 per cent, linalyl acetate. In 

 reality, however, this content is considerably smaller and can approximately be cal- 

 culated from the acid value II, which would correspond to a linalyl acetate quantity of 

 22.2 per cent. As indicated above, this oil also gives decidedly the impression of an 

 artificial product whose manufacture has been a complete failure. 



A sample handed to us for investigation by a Leipzig firm, with the proud title 

 "Oleum Bergamottce la Beggio red. pur.", was simply an artificial, about 80 per cent, 

 linalyl acetate, as its constants prove: di 5 o 0.8997; « D — 10° 11'; n D20 o 1.45082; acid v. 1.9; 

 ester v. 233.3, corresponding to 81.7 percent, linalyl acetate, soluble in 2.7 vol. and 

 more of 70 percent, alcohol. 



Sweet Orange Oil. A sweet orange oil which recently came to hand, is also 

 worth mentioning at this point, to serve as a warning. It was quite sufficient to 

 determine the specific gravity and optical qualities of it, in order to form an opinion 

 on its quality. The constants indicated were as follows: di 5 o 0.8662; a D25 o + 58° 18'; 

 a D of the first 10 percent, of the distillate +56° 20'. Compare with this the charac- 

 teristics of genuine sweet orange oil, namely, at 15° a specific gravity of 0.848 to 

 0.853 and an optical rotation of +95° 30' to +98°; the first 10 per cent, of the oil 

 having a rotation not measurably less than the original oil. 



The extreme divergence from the normal figures makes it quite obvious that the 

 sample is at least greatly adulterated. Probably, however, this is an artificial product 

 in which lemon oil terpenes have been employed, whereas orange oil is entirely absent, 

 which can be inferred, above all things, by the exceedingly low degree of rotation of 

 the first 10 per cent, of the distillate (boiling above 172°). However that may be, 

 there is at least no doubt that this is again a case of a most vulgar fraud. 



G. C. Hood 1 ) publishes an account of the oil content of Florida oranges. At various 

 periods he collected the oranges during harvest time and made a determination of 

 the oil value of the peel. Thereby the fact came to light that conditions of climate 

 and culture greatly influence the oil content of the fruit which besides varies con- 

 siderably with the species. Only when fully ripe does the peel contain its highest 

 percentage of oil, it is, however, sufficiently great to permit of collecting even in 

 unripe fruit which cannot be gathered. Rain during harvest reduces the oil yield 

 considerably. The occurrence of a rust mite has no effect on the oil yield of the ripe 

 fruit. In tabulated form Hood reports on the weekly oil yield for 8 orange varieties 

 from 17 different localities in Florida. 



As to the export of lemons and oranges from Syria, see p. 107. 



*) Journ. ind. eng. Chemistry 8 (1916), 709; Perfum. Record 7 (1916), 310. 



