Styrax (FAO, NWFP 6)
- See the main page Copal (in French)
- Extract from : NWFP 6. Coppen J.J.W., 1995. Gums, resins and latexes of plant origin. FAO, Rome. 142 p. (Non-Wood Forest Products, 6). on line
[87]
Contents
DESCRIPTION AND USES
Styrax, sometimes called storax, is a balsamic oleoresin obtained from trees of the genus Liquidambar. So-called Asian styrax comes from Liquidambar orientalis of Asia Minor, while American styrax is obtained from Liquidambar styraciflua of Mexico and Central America.
Asian styrax is a semi-solid, sticky brown mass, somewhat heterogeneous in both colour and consistency. American styrax is usually darker, but cleaner, than Asian styrax. Like other balsams, both contain cinnamic acid or derivatives of cinnamic acid, although in the case of American styrax the typical balsamic odour is masked by a styrene-like odour.
An essential oil can be distilled from both types of styrax and this is more widely used by the fragrance industry than the oleoresin itself. It has a rich, balsamic odour and is often used in floral-type perfumes. Extraction of the crude oleoresin with an appropriate solvent furnishes a number of "resinoids" or "absolutes" which are also used in perfumery.
There has been some minor use of the balsams in pharmaceutical preparations such as bronchial medicines, and there is still some local use for medicinal purposes, particularly with oleoresins from some of the Asian species of Liquidambar.
WORLD SUPPLY AND DEMAND TRENDS
Markets
Trade statistics for styrax are not readily available, and in most cases importing countries do not separate it from other gums and resins. Consumption of both types of styrax might total a few hundred tonnes at most.
Exports of Asian styrax from Turkey ranged from 50 tonnes to 70 tonnes annually in the period 1961-69. The main importers then were the United Kingdom (the largest), Germany, France, Italy and the United States. Europe, where there are many processors and producers of essential oils and oleoresin extracts, probably remains the most important market for Asian styrax. The United States is the largest importer of American styrax.
Supply sources
Turkey is the only source of internationally traded Asian styrax, and since domestic consumption is small, the export data given above are a reasonable reflection, also, of production.
Most American styrax comes from Honduras, although Guatemala (and, to a lesser extent, Nicaragua) has produced small amounts in the past. The size of production from this region is not known.
Quality and prices
Asian styrax is impure and, as a result of its method of production, often contains substantial amounts of water. American styrax is slightly darker but generally of better quality.
[88]
An EOA standard specifies certain physico-chemical requirements for oil of American styrax.
Published commodity prices (mid-1995) list Turkish styrax at about US$ 11.75/kg, CIF London.
PLANT SOURCES
Botanical/common names
Family Hamamelidaceae:
- Liquidambar orientalis Mill. - Asian styrax/storax
- Liquidambar styraciflua L. - American styrax/storax
Description and distribution
Liquidambar orientalis is a medium-sized tree, usually 6-12 m tall but sometimes higher. It is native to Turkey and surrounding regions.
Liquidambar styraciflua is a large tree which grows wild in some parts of the southern and eastern United States, and in Mexico, Honduras and Guatemala.
Liquidambar formosana H. occurs in Southeast Asia (People's Republic of China, Viet Nam and elsewhere) but the oleoresin, although used locally, is not believed to enter world trade.
COLLECTION/PRIMARY PROCESSING
In Liquidambar orientalis, the balsam is present in the sapwood and bark of the tree. The traditional method of obtaining Asian styrax is to remove pieces of bark and boil them in water. The crude, softened balsam separates out and settles to the bottom of the vessel, from which the water is subsequently decanted. Further quantities of balsam are obtained by pressing the "extracted" bark to remove any residual material. Some styrax is also obtained by making incisions into the exposed stemwood and either collecting the exudate in small cans fixed to the tree or scraping it off directly.
Preliminary cleaning of Asian styrax is undertaken by combining the different lots of crude balsam and washing it in boiling water. The dirty water is again removed by decantation and the soft, fluid oleoresin is separated from the lower layer of sand, dirt, etc.
In Honduras, it is more usual to collect the styrax by tapping only, without treatment of the separated bark. A small gutter and cup are fixed to the tree and a cut is made in the stem where the pockets of balsam are located.
Yields
No reliable yield data are available, although it is known that there can be considerable tree-to-tree variation. In the older literature, average yields of around 20 kg of balsam per tree were claimed for American styrax in Honduras.
[89]
VALUE-ADDED PROCESSING
As already noted, crude styrax is rarely used as such. Steam distillation of the oleoresin yields an essential oil which is of more value than the oleoresin itself. The crude balsam is often saponified prior to distillation to release cinnamyl alcohol.
Extracts are also widely used and are prepared using hydrocarbon or alcoholic solvents.
PRODUCTS OTHER THAN RESIN
No other products of economic value are known to be obtained from the trees.
DEVELOPMENTAL POTENTIAL
A judgement on the developmental potential of styrax requires a greater knowledge of the demand for it than is presently available. If labour costs in Turkey increase to the point where it becomes uneconomic to produce, or the people becorne less inclined to want to undertake the tasks involved in production, then there may be opportunities for producers of styrax from other botanical sources, particularly those in Southeast Asia. This would depend, however, on the balsam (and the oil and extracts derived from it) having quality characteristics that make it acceptable to end-users.
Research needs
Apart from market research, including Japanese and other Asian markets (as outlets for any balsam from newly developed Asian sources), it would be desirable to examine the properties and quality characteristics of alternative sources of styrax. Only if these preliminary investigations showed promise would it be worth expending more effort in examining the technical and economic aspects of production.
- Phytochemical screening and trade evaluation. Collections of oleoresin should be made from a number of provenances of Liquidambar formosana and other Asian species of Liquidambar. After preliminary analysis and preparation of the essential oil, samples should be assessed for commercial value by traders and/or end-users, both local and international.
SELECTED BIBLIOGRAPHY
- ADAMSON, A.D. (1971) Oleoresins. Production and Markets with Particular Reference to the United Kingdom. Report G56. London: Tropical Products Institute [now Natural Resources Institute, Chatham].
- BOELENS, H.M., de RIJKE, D. and HARING, H.G. (1982) Studies of some balsamics in perfumery. Perfumer and Flavorist, 6(6), 7-14.
- EOA (1975) Oil styrax. EOA No. 153. 2 pp. Essential Oil Association of USA.
- FURIA, T.E. and BELLANCA, N. (1971) Storax. pp 231-233. In Fenaroli's Handbook of Flavour Ingredients. Cleveland, USA: The Chemical Rubber Co.
- GUENTHER, E. (1952) Oil of styrax. pp 243-254. In The Essential Oils, Vol. 5. New York: Van Nostrand Co.
[90]
- IGOLEN, G. (1972) [Anatolie styrax] (in French). Rivista Italiana EPPOS, 54, 554-558.
- IVANOV, C.P., YANKOV, L.K. and THO, P.T.T. (1969) On the composition of the essential oil from the resin of Liquidambar formosana H. Rivista Italiana EPPOS, 51, 380-384.
