The dried inner hark of C. verum contains a steam-volatile oil, fixed oil, tannin, resin, proteins, cellulose, pentosans, mucilage, starch, calcium oxalate and mineral elements. The relative abundance of these components can vary somewhat according to the geographical origin of the spice, its quality and the duration of storage.

Collaborative studies between the Imperial Institute and the Seychelles ‘Agricultural Department to improve the quality of the product showed that the cinnamaldehyde content was similar to that of Sri Lankan bark oil but the eugenol content could range from 2 to 8 per cent – usually 3 to 5 per cent. Camphor was not identified in the oil in these investigations.

The oleoresin may be prepared by extracting cinnamon bark with a variety of organic solvents. It contains the steam-volatile oil, fixed oil and other extractives of the spice soluble in the particular solvent employed. Little published information is available on the detailed composition of cinnamon oleoresins, but the volatile-oil content has been reported to range upwards from 16 per cent.

The characteristic organoleptic properties of the spice and its oleoresin are determined by the composition of their steam-volatile (essential) oils. The small amount of coumarin present also influences the flavour but other non-steam-volatile constituents appear to be unimportant. Detailed analyses of the composition of the natural steam-volatile oil occurring in the spice have not been reported, and its composition must be inferred from the information available on the distilled bark oil. The latter, however, contains some artefacts produced by the distillation procedure and is less esteemed than the spice and oleoresin in organoleptic terms.

Only a few studies of Malagasy cinnamon hark oil have been reported. Distillation in Europe of imported material gave oils in yields of 0.6 to 1.0 per cent, which possessed aldehyde contents of 62 to 65 per cent. Guenther’s oil contained 10 per cent phenols and its odour was considered inferior to that of Sri Lankan bark oil but superior to oils from other sources.

Analytical data for C. verum bark grown in the Malagasy Republic and some other French colonial territories have been reported by Jaeger and Duquenois (1949) and Paillot-Cressole and Duquenois (1952). These authors express some doubt as to whether the trees in the Malagasy Republic are true C. verum.