Commercial and scientific notes on essential oils. 19 



his ingredients; for a mixture of glycerin acetate and the methyl ester mentioned bears 

 very little resemblance to bergamot oil. 



With respect to the physical and chemical properties of the bergamot oils produced 

 in 1920 21 in Calabria, a memoir by A. Parrozzani 1 ) should be mentioned. We see from 

 this paper and its tables that the oils had mostly a high specific gravity, yet not ex- 

 ceeding the normal limits in general, viz. 6 15 o 0.8801 to 0.8874; that the optical rotation 

 was in general higher than 22° (up to 37°); an that the solubility of the oil in alcohol 

 was lower than it had been in the preceding year, but that this figure also remained 

 within normal limits. (1 vol. of oil was soluble in 0.8 vol. of alcohol of 85 per cent, 

 and in 0.5 vol. of alcohol of 90 per cent.). The first fraction of the distillate (one third 

 of the oil), gave only in three cases twice as large a rotation as the oil. The ester 

 content amounted to 30 to 40 per cent., in some cases to 45.76 per cent. 



Parrozzani has evidently been experimenting also with oils which had been expressed 

 at the beginning of the harvest from unripe fruit which the storms had brought down 

 from the trees. That would help to explain the deviations from the normal in specific 

 gravity, ester content and solubility which he observed, though it would not suffice 

 to explain rotations of +37°. So high values have so far only been found when the 

 respective bergamot oil contained lemon oil or orange oil. The results of Parrozzani's 

 study can, of course, not be utilised for the valuation of the bergamot oils of the trade 

 in which we have to deal with average products. 



Lemon Oil.— This important oil is still depreciating in value, and the end of the 

 down grade movement can not yet be foreseen. The demand was especially weak in 

 February, a month which, as the export statistics which we gave above will indicate, 

 was exceptionally quiet in the market of essential oils. Rumours which became current 

 again from time to time of a total stock exhaustion in the countries of consumption 

 do not appear to have been justified; for the retrogressive price movement had not 

 come to its end by March and a stronger demand was still in vain looked for. 



It is well known that the properties of lemon oils depend much upon the season 

 and upon the state of maturity in which the fruit are gathered 2 ). According to A. Boake, 

 Roberts 8j Co., Ltd. 3 ), the lemon oils prepared at the beginning of the season, that is, 

 in December and January, possess the highest citral content and the highest optical 

 rotation, as well as the lowest density and the relatively smallest amount of non-volatile 

 residue. The yield of oil is, moreover, best in this season. In the measure as the fruit 

 ripens, the content of citral in the oil diminishes and the proportion of waxy constituents 

 increases. As a consequence the solid residue which, at the beginning of the season, 

 will amount to about 2 per cent., may rise to 3 per cent, and more by May. 



We have not been able to observe any particular regularity in this report. (Cf. Report 

 November 1908, page 63, as well as E. M. Chace, The Occurrence of Pinene in Lemon 

 Oil. United States Department of Agriculture, Bureau of Chemistry, Circular No. 46, 

 page 15 to 19 [30. X. 1909.]). 



As regards the different lemon oils of Sicily we have another paper by Boake, 

 Roberts % Co. 4 ) In a somewhat modified and expanded form we find there stated what 



') Le propriety fieiehe e chimiclie delle essenze di bergamotto prodotto in Calabria nella campagna agriimaria 

 IteO — Kjul Annali dalla JR. Staz. Sperim. per Vindustria delle essenze e dei derivati dagli agrumi 1 (1921), 1. 

 Reprint kindly sent to us. — 2 ) Gildemeister and Hoffmann, The Volatile Oils, 2 nd ed., vol. Ill, p. 16. — 

 ') Drug aad Chem. Markets 7 (1920), 339. — *) Perfum. Record 11 (1920), 249. 



2* 



