2. Cassia or Chinese cinnamon is from Cinnamomum Cassia, a tree which grows wild in the forests of Southern China. The bark is thicker than that previously described, often 2 mm thick. It is in single tubes, harder and thicker than the Ceylon kind, with frequently adherent fragmentary tissues of the corky layer. The colour is a greyish brown, the fracture even, with a light zone in the section.
3. Malabar or wood cinnamon consists of the less valuable kinds and is derived from different varieties of cinnamon trees which have been planted in the Sunda and Phillipine islands. In appearance it resembles the Chinese more than the Ceylon cinnamon.
The aromatic taste of cinnamon is due to the ethereal cinnamon oil which, in Ceylon cinnamon, amounts to 1 percent; the ash should not exceed 4·5 percent. An ethereal oil is also present (about 1·8 percent) in the leaves of the Ceylon cinnamon tree, but it is quite different from the bark oil, resembling in its properties more the oils of cloves and pimento. On account of its penetrating odour and pungent taste its employment in chocolate making is little to be recommended.
It cannot be too much insisted on that with spices like cinnamon, cloves, etc. the manufacturer should grind them himself and not purchase them in fine powder, as the latter is frequently adulterated with admixtures of wood, meal bark, etc. This is more to be recommended as ground cinnamon has frequently been deprived of the ethereal oil by distillation with steam and the bark then flavoured with a small amount of cinnamon oil and sold as powdered cinnamon. Such an adulteration can be detected neither chemically nor microscopically.
e) Cloves.
Cloves are the incompletely developed flowers of the clove tree, Caryophyllusaromaticus of the Myrtaceae. The most important commercial kinds are the Zanzibar, Amboyna, and Penang cloves. The aromatic principle of cloves is an ethereal oil which they contain to the extent of 18 percent. The adulteration of cloves is much the same as in the case of cinnamon. Genuine cloves should not give more than 6 percent of ash.
f) Nutmeg and Mace.
Nutmeg is the seed kernel of the fruit of Myristica moschata known as the nutmeg tree, which is indigenous to Malacca. In the thick pericarp of the fruit, resembling the apricot, is found the brown seed surrounded by a deep red reticular mantle. This last is the seed mantle or arillus and when separated from the kernel is known commercially as mace.
The furrows on the surface of the nutty seeds are filled with a white mass which consists of lime, in which the nuts have been laid after drying in order to protect them from the attack of insects. The aromatic constituent of nutmeg and of mace is also an ethereal oil. The seeds contain 8-15 percent of ethereal oil with 25 percent of a fatty oil; mace contains 4-15 percent of ethereal oil and 18 percent of fatty oil. As both spices occur in commerce in whole pieces, adulteration is not to be feared.