Ginger Oil

#### Ginger Oil. **Ginger**** ****Oil**** **is produced by steam distillation, occasionally by water-and-steam distillation of the dried, unpeeled, freshly ground rhizomes of **Zingiber Officinale**, a plant which is native to the tropical coastal regions of India. The rhizomes, sun-dried and unpeeled, have been known as a spice for several thousand years, and the plant was among the early introductions to the West Indies when the Spanish seafarers roamed the Caribbean Sea shortly after A. D. 1500. The ginger plant is now cultivated in most tropical and subtropical regions, e.g. Jamaica, Indochina, Southwest India, Ceylon, West Africa (particularly Sierra Leone and Nigeria), south China, south Japan and Central America. Smaller crops are grown in Madagascar (Nossi-Bé), Indonesia, Zanzibar, northwest Australia, Haiti, The Dominican Republic, Cuba and other areas of the West Indies. For the production of essential oil, the Nigerian and the Jamaican gingers are the most important. It is worthwhile noting that the term “African ginger” refers to Nigerian ginger when we speak of **Ginger Oil**, while it generally means Sierra Leone ginger when the *spice *itself is discussed. Sierra Leone ginger is usually sold as a spice for grinding, while Nigerian ginger—which is always unpeeled—is mainly used for the distillation of essential oil and for extraction of **Ginger**** ****Oleoresin **(see following monograph). Jamaican ginger is partially peeled and, accordingly, is lighter in color. Since the essential oil is located in cells immediately under the epidermis, peeling of the rhizome will inevitably result in a loss of essential oil, either by accidental removal of oil cells, or by resinification or evaporation of oil caused by exposure of the oil cells to the air. Jamaican ginger accordingly yields considerably less oil than does the Nigerian ginger, and there is a distinct difference in the olfactory characteristics of the two oils. The odor of Nigerian ginger oil is heavier, more grassy-fatty, oily and woody than that of the Jamaican oil. An individual odor description is given below. There is no production of ginger oil in Nigeria, while the oil is produced on a small scale in Jamaica, Zanzibar (experimental stage), India, China and Japan. The largest proportion of all the ginger oil of commerce, however, is produced in Europe and the U.S.A. from rhizomes imported from Nigeria, Jamaica and the Far East. In Japan, an oil is distilled from locally grown ginger, but this oil has a different aroma, and is only of local interest. The author had an opportunity to follow the development of experimental ginger production in the Gold Coast in 1954 to 1956 (now Ghana), and he had fresh rhizomes shipped from that country to Denmark. The water content in the fresh rhizomes was found to be from 68 percent to 73 percent. The water content in commercial grades of dried ginger rhizomes varies from 12 to 20 percent. This is mentioned to emphasize the importance of drying ginger rhizomes (and other botanicals) prior to shipment (costly freight of unnecessary water, deterioration of the spice, hydrolysis of oil constituents, etc.). **Ginger Oil **is a pale yellow to light amber- colored mobile liquid. Its viscosity increases upon ageing or exposure to air (resinification). The odor is warm, but fresh-woody, spicy and with a peculiar resemblance to orange, lemon, lemon- grass, coriander seed oil, etc. in the initial, fresh topnotes. The sweet and heavy undertone is tenacious, sweet and rich, almost balsamic-floral. African ginger oil is generally darker in color and presents a more fatty sweetness. The freshness is not pronounced nor is it very characteristic of that type ginger oil. It is, however, extremely rich and tenacious. Jamaican ginger oil is usually very pale in color, mobile like a pine needle oil, and with a pronounced odor-freshness of lemon- orange-coriander-like character. The body is sweet but not balsamic, the tenacity is only moderate. The initial notes of freshly distilled **Ginger**** ****Oil**** **from Jamaican rhizomes often have a peculiar “rubber”-like type, similar to that of freshly distilled nutmeg oil (myrcene-like notes?). This note is hardly ever perceptible in African ginger oil. There is no pungency in the flavor of any of the ginger oils. The flavor is warm and spicy, slightly bitter at high concentration, but pleasant-aromatic at ordinary use level. The suggested use level for an average good grade of Jamaican ginger oil is 0.30 to 1.50 mg%, and the **Minimum Perceptible **is 0.02 to 0.05 mg%. See also **Ginger Oleoresin **which is generally preferred as a flavor material, representing all the characteristics of the ginger rhizome itself. **Ginger Oil **is used in perfumery to introduce warmth and certain nuances of spicy sweetness which are often wanted in heavy Oriental bases and in a few floral fragrances, too. The interest in the oil for perfumery use has increased considerably during the recent years of the growing “spice-trend” in men’s fragrances and in lotion perfumes in general. The oil blends well with bois de rose oil, cedarwood, coriander, coumarin. berizyl acetate, citrus oils, eugenol, ionones, nitromusks, rose de mai absolute, nonanolide, nerol. etc. The Jamaican oil lends more freshness and topnote, while the Nigerian oil will give a solid body note, a warmth which is quite unique and typical of this oil. In flavors, traces of **Ginger Oil **have an interesting effect in strawberry, pineapple, peppermint (modifier), but the most important field by far is that of baked goods: cookies, powder cakes. spice cakes, where pungency is not particularly called for. (Ginger nuts are flavored with **Ginger Oleoresin*****). ***In alcoholic beverages, the oil gives interesting twists to the herbaceous types of liqueurs (benedictine, etc.), while the non-alcoholic beverages, e.g. the carbonated ginger ale is usually flavored with ginger oleoresin, or with a mixture of ginger oleoresin, ginger oil, capsicum oleoresin and sweet orange oil. Ginger oil blends well with sweet orange oil, lime oil, bergamot oil, etc. in flavor compositions. The oil is produced according to demand, and there is ample supply of the spice available. Deliberate adulteration can be made with galanga oil (China and Japan), but usually the differences in the quality of the oils can be traced back to lack of experience in distillation technique at the producer’s place, or poor selection of botanical material for distillation. The annual world crop of ginger is in the order of magnitude of 100 million lbs. of fresh, undried rhizomes. This quantity corresponds to about 10,000 to 15,000 metric tons of commercial grade, dried ginger rhizomes. A very large proportion of this quantity is absorbed in households in the Far East, particularly in India.