Oil of Orange Flowers (Oleum Naphæ, Oleum Neroli),
commercially known also under the French names huile de fleurs d’oranges, huile néroli, huile néroli pétale, is obtained from the flowers of the orange-tree in Southern France, where the orange is specially planted for this purpose. The odor of the oil varies with the mode of its preparation; that obtained by distillation with water has a different odor from that made by maceration with fat and extraction with alcohol. The latter variety of oil as such, however, is not found in commerce, the alcoholic extract entering at once into the composition of the perfumes.
The French manufacturers of this oil, which is of great importance in perfumery, distinguish several varieties. The most valuable is the oil from the flowers of Citrus vulgaris (or Citrus Bigaradia), the true bitter orange (or Seville orange) tree. This is the so-called néroli bigarade. That called néroli pétale is obtained from the same flowers carefully deprived of their floral envelopes, so that only the petals are subjected to distillation. Much cheaper than these two is the oil of petit grain which is distilled from the leaves and sometimes also unripe fruits of various trees of the Citrus order.
All these oils are among the most delicate; when fresh they are colorless and have a peculiar bitter taste; exposed to light and air they assume a reddish tint and undergo rapid resinification. They should, therefore, be preserved in particularly well-closed vessels in a dark, cool place.
Not to be confounded with these oils is the
Oil of Orange,
of which there are two kinds, one from the bitter orange, known also as Oil of Orange, Bigarade, and the other from the sweet orange, also known as Oil of Portugal. Both are extracted from the peel of the fruit by mechanical means. Both oils of orange peel are golden yellow, and have a pleasant, refreshing odor recalling that of the fruit. They find application for scenting soap, in toilet waters, and in some true perfumes. When oil of orange or oil of orange peel is mentioned in any formula, without further specification, the oil of bitter orange peel should be used.
Oil of Patchouly.
This oil, which might be manufactured with advantage in India, the home of the plant, is, strange to say, not imported from that country, but is distilled in Europe from the dried herb. Fresh oil of patchouly is brown in color, very viscid, almost like balsam, and surpasses all other essential oils in the intensity of its odor. Owing to the strong odor, pure oil of patchouly must really be called ill-smelling; only when highly diluted does the odor become pleasant, and then forms a useful ingredient of many perfumes as the fundamental odor in the harmony.