Clove Bud Oil

#### Clove Bud Oil. **Clove Bud Oil **is water distilled (rarely steam distilled) from the dried flower buds of **Eugenia**** ****Caryophyllata**, a slender, medium-sized, tropical tree, originating in the Moluccas, particularly the island of Amboyna in the eastern Indonesian archipelago. The original wild clove tree from the Moluccas does not produce a eugenol-containing essential oil at all. This wild tree still grows in the islands among plantations of cultivated trees. The cultivation of clove trees is at least 2000 years old. **Clove Bud Oil **is the largest of the essential oils produced from “stable” material which is brought to European or American distilleries thousands of miles from the areas where the cloves grow. No clove bud oil is produced in the clove growing areas. Madagascan, Zanzibar or Comoro clove buds are used for the distillation. Amboyna clove buds are usually sold as the highest grade of the whole spice. The yield of essential oil by water distillation of the clove buds is about 15%. Up to 20% of the world production of clove buds is used for distillation, but the figure fluctuates with the immediate cost of the cloves. The clove buds are comminuted prior to distillation. During the water distillation of clove buds, certain materials are formed in the essential oil which do not exist in the clove bud in natura, e.g. Caryophyllene and possibly other sesquiterpenes. The same happens during steam distillation, but not during a low-temperature hydrocarbon-extraction of the buds (see monograph on **Clove Bud **Absolute). If the cloves are steam distilled, hydrolysis takes place, and most of the natural acetyl eugenol (aceteugenol) is converted to eugenol. Since this hydrolysis takes place only to a minor degree during water distillation, the latter method is accordingly preferred. Water distilled clove bud oil has a very high content of “total eugenol” (usually over 92%), but a substantial part of this is aceteugenol (10 to 15%*) *which is partly responsible for the characteristic odor of clove bud oil. The author wishes to extend his acknowledgements to a well known English distiller and expert in spice oils for this simple and handy test on clove oils: “add a few drops of the clove oil sample to an aqueous paste of magnesium hydroxide, stir well, and leave overnight in a closed beaker. The eugenol is then fixed as an odorless magnesium salt while esters of eugenol, methyl-n-amyl ketone, etc. are not affected by the magnesium hydroxide. If pure clove bud oil was used in the experiment, the odor of the mixture the next day will be a strong, pure clove odor”. This experiment emphasizes the importance of trace elements among the odor principles in essential oils. The quality of a clove oil can not be judged by the eugenol content of the oil (unless the oil is purchased for the purpose of isolating eugenol). Trace amounts of lower aliphatic ketones lend this oil a peculiar fruity-fresh topnote, and a touch of an acetic odor makes it quite refreshing and distinctly different from clove stem oil which may even have the same content of “total eugenol”. The acetic note could very well derive from traces of acetic acid, produced from the aceteugenol which even in a gentle water distillation hydrolyzes to some degree. The eugenol note in a good clove bud oil is distinctly subdued, sweetened and freshened by the presence of the above mentioned materials in the bud oil. **Clove Bud Oil **is used frequently in perfumery for its sweet-spicy note, but the largest part of all clove bud oil by far is used in flavor work. In perfumes, clove bud oil blends well with its derivatives, e.g. aceteugenol, methyl eugenol, isoeugenol, vanillin, “ethyl-vanillin”, etc. to form part of the well-known “carnation” base. In rose, honeysuckle and certain deep-sweet florals, clove bud oil lends a unique note of natural richness and body. The classic *“rondeletia” *perfume type is based upon the combination of clove and lavender oils. Modern variations include the use of lavandin, sage clary, bergamot, bay leaf oil, pimenta berry oil, etc. The oil blends excellently with ylang-ylang and cananga oils, and Oriental types of perfumes often contain significant amounts of clove bud oil. **Clove Bud Oil **is used extensively in flavors in a large variety of food products: spice blends, seasonings, pickles, canned meat, baked goods, powder cakes, ready-made mixes etc. Due to its well-known antiseptic effect, the oil finds its way into numerous mouth washes, gargles, dentifrices and pharmaceutical and dental preparations. Candy, particularly chewing gum, is also flavored with clove bud oil in combination with other essential oils. The suggested use level for a high- grade clove bud oil is 1.00 to 3.00 mg%, while the **Minimum Perceptible **is 0.15 to 0.30 mg%. Wide variations in the figures for the use level must be expected according to the specific use of the oil in each case. The annual world production of clove bud oil fluctuates according to the price of the buds. 300 to 500 tons has been the annual output in recent years. This corresponds to 2100 to 3500 metric tons of clove buds distilled, or: 10 to 15 percent of the annual clove bud production. This huge progress in clove bud oil production has brought the price down to an all-time low, a fact which is interesting to study along with the fact that eugenol has not yet been synthesized on a commercial scale. The fluctuating production of clove bud oil is not a true picture of the demand for clove bud oil. The price of the buds is strongly dependent upon the demand for clove buds in Indonesia. That country is the largest customer for the clove bud growers. Comminuted clove buds are used to the extent of up to 8% in Indonesian cigarette tobacco. If this peculiar need for “spicy smoke” should fade away, there will be an enormous surplus of clove buds on the market. The price will drop, and clove bud oil can be produced at a fraction of its normal price. The spice houses can keep clove bud oil for many years, and a large stock does not require much space. The adulteration of clove bud oil could be described in immediate connection with the above remarks of demand for clove buds. At the present moment (1960) there is only little profit in the “cutting” of clove bud oil with clove stem oil or rectified clove leaf oil. Eugenol and caryophyllene, two of the main constituents of all clove oils, are not produced synthetically on a commercial scale. Accordingly, there is no reason for adulteration of clove bud oil until its price increases twice or three times, and that is not very likely.