Elemi (FAO, NWFP 6)
- See the main page Élémi (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). en ligne
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Contents
DESCRIPTION AND USES
The term "elemi" has been applied in the past to a large number of oleoresins from a variety of geographic and botanical sources (see PLANT SOURCES below). Nowadays, however, the term is almost always used to describe the product from the Philippines, Manila elemi, which is the only one that is traded internationally, and most of the rest of the discussion focuses on this.
Manila elemi is the soft, fragrant oleoresin obtained from the trunk of Canarium species, the most important of which is C. luzonicum. When fresh, the oleoresin is oily and pale yellow or greenish in colour, resembling crystallized honey in consistency, but on exposure to air it loses some of the volatile constituents and hardens. It has a balsamic odour and a spicy, rather bitter taste.
In the forest areas where it is collected it is rolled in leaves and used for lighting purposes, but in commerce it is used mainly by the fragrance industry after distillation of the essential oil. It still finds occasional use as an ingredient in lacquers and varnishes, where it gives toughness and elasticity to the dried film.
WORLD SUPPLY AND DEMAND TRENDS
Markets
Exports of Manila elemi from the Philippines for the period 1988-93 are given in Table 27. Annual totals have been somewhat erratic but average almost 300 tonnes, with a peak of over 600 tonnes in 1990.
France is the largest single market, accounting for up to three quarters of the total exported from the Philippines, and it is presumed that the elemi is used principally or solely for fragrance purposes. Germany is the second biggest market, and exports to Japan have increased slowly but significantly. The United Kingdom, United States and Switzerland are other, sometimes erratic, importers.
The trend is difficult to predict but, at least, does not appear to be down, and with continued supply of elemi the market is likely to be able to sustain levels of around 200-300 tonnes annually.
Supply sources
Although the source of Manila elemi, C. luzonicum, occurs on other islands in the Pacific (where it may have potential for exploitation; see DEVELOPMENTAL POTENTIAL), the Philippines are the only source of internationally traded elemi. Export figures are as given in Table 27.
Quality and prices
Three classes of Manila elemi exist for domestic and export trade, although the designations are not always adhered to: class I (within which there are two grades), class II (two grades)
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and class III (one grade). Class I represents the palest material (the two grades being clean or non-clean), class II a more yellowish material, and class III a mixture of I and II. The softer grades are the higher quality, reflecting a higher essential oil content compared with the harder grades.
In the last four years for which data are available, the FOB export value per kg for Manila elemi has been US$ 1.74 (1990), US$ 1.73 (1991), US$ 1.67 (1992) and US$ 2.08 (1993). Currently (mid-1995) there is reported to be a shortage and prices quoted by London importers are in the range US$ 4.20-4.50/kg (cf US$ 2.25/kg a year earlier). Prices for elemi fluctuate more than for most other resins.
PLANT SOURCES
Botanical/common names
Family Burseraceae:
| Canarium luzonicum (B1.) A. Gray (syn. C. polyanthum Perkins, C. olignanthum Merrill) | Pili, piling-liitan (resin: elemi, sahing, brea blanca) |
| C. ovatum Engl. | Pili nut |
| C. indicum L. (syn. C. commune L., C. amboinense Hochr.) | Java almond, kenari nut, ngali nut |
| C. schweinfurthii Engl. |
C. luzonicum is probably the only source of commercially traded Manila elemi, although C. ovatum, C. indicum and C. schweinfurthii are known to produce resin which is, or has been, used locally. Other species of Canarium undoubtedly produce resin if wounded.
Other genera which yield gums or resins which have been traded in the past as elemis include Protium (which produces "breu branco" or Brazilian elemi), Amyris (Mexican elemi) and Dacryodes (West Indian elemi). They are not discussed further.
Description and distribution
Canarium is a genus of big shade trees in the Old World tropics, chiefly Malaysia to the Philippines, but extending to Papua New Guinea and other Pacific islands, which are often highly prized for their edible fruits and nuts. C. luzonicum is a large tree up to 35 m tall and 1 m in diameter. It is found in primary forests at low and medium elevations in Luzon and some other islands of the Philippines.
C. ovatum is a large, buttressed tree, reaching up to 20 m in height, and native to the Philippines.
C. indicum reaches as high as 40 m and occurs in parts of Malaysia, Indonesia, Papua New Guinea, the Solomon Islands and other islands in the Pacific.
C. schweinfurthii grows to 50 m in height and is found outside the usual Canarium region, in tropical West and Central Africa. In the past it has been an occasional source of "African elemi".
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COLLECTION/PRIMARY PROCESSING
In a survey of tapping methods practised in the Philippines (ALONZO and ORDINARIO, 1972), tappers used a sharp "bolo" and a wooden mallet to make a series of cuts up the trunk of the tree, each cut resulting in removal of bark and exudation of the oleoresin. The diameter of the trees tapped was in the range 20-60 cm. The initial strip of bark which is removed should be 2 cm high and not more than 30 cm wide. Subsequent strips (1 cm high) are removed at approximately two-day intervals above and adjacent to the previous one, and tapping is continued as high as the person can reach. A second face may be opened close to the first, providing at least one third of the circumference of the bark of the tree is left intact.
The exuded, sticky mass is collected at two-week intervals, usually by scraping it off the tree with a blunt-tipped bolo or stick.
After transport to the towns, elemi which is destined for export is cleaned by manual removal of as much bark and other forest debris as possible. The cleaned resin is then packed in polythene-lined kerosene cans.
Yields
Yields are known to vary from tree to tree, but no reliable quantitative data are available; yields of 4-5 kg of resin per tree annually have been reported in the older literature. Tapping is usually a year-round activity, but resin flow is at its greatest during the rainy season and little, if any, may be collected in the dry months.
VALUE-ADDED PROCESSING
The crude oleoresin contains a high proportion of essential oil, around 25%, and this can be recovered by the simple process of steam distillation. The freshly distilled oil is liable to resinify and polymerize on standing, and for this reason distillation is normally carried out in the importing country, where it can be formulated soon after preparation.
A resinoid is also sometimes prepared by solvent extraction of the crude elemi.
PRODUCTS OTHER THAN RESIN
Although usually restricted to local use, many species of Canarium are used as sources of edible fruits and nuts, and provide valuable fat and protein in the diets of very many people in the Pacific region. The Chinese olive, from C. album, is exceptional in being exported to other regions of Southeast Asia and, occasionally, further afield. Recent work in the Solomon Islands on the ngali nut (from C. indicum var. indicum) has shown this, too, to have considerable promise as an export item, although it is not known whether the tree is also a potential source of resin.
It has been suggested that the essential oil of C. luzonicum could be blended with diesel oil and used as a motor fuel, but at the moment this application remains speculative.
DEVELOPMENTAL POTENTIAL
C. ovatum and some other resin-yielding species of Canarium are already grown as sources of fruits and nuts and integration with resin tapping would be a welcome development,
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providing one does not adversely affect the other. The method of tapping described is not unlike that used to obtain resin from pine trees, and if the international market can absorb more elemi, there are grounds for optimism that improved methods of tapping Canarium could be developed which would lead to higher yields of better quality oleoresin than at present.
Research needs
Some work to develop improved varieties of Canarium for fruit and nut production has already been carried out, and since cultivation for this purpose is likely to remain the primary activity, research on resin production should be complementary to that on fruit and nuts. Several aspects need to be researched:
- Comparative evaluation of different Canarium species for dual purpose fruit/nut and oleoresin production. Although C. /uzonicum is the present source of Manila elemi, its productivity should be compared (in terms of both fruits and oleoresin) with C. ovatum, C. indicum and, possibly, other species, to determine which might offer the best combination for maximizing economic returns. As a first step, however, a laboratory and trade assessment of the resin from each species should be made to determine whether the non-traditional elemis would be acceptable in the market-place. *Germplasm screening for elite planting stock. As has been noted elsewhere with other gum and resin-yielding species, natural populations of Canarium (particularly C. /uzonicum) should be screened to determine provenance and tree-to-tree variation in oleoresin yield and composition. *Improved methods of tapping. This should draw on experience in the gum naval stores (pine tapping) field and include an examination of the use of cups (such as coconut shells) to collect the resin which runs down the tree in order to produce a cleaner product.
SELECTED BIBLIOGRAPHY
- ABARQUEZ, A.H. (1982) Pili management for resin and nut production. Canopy International, 8(4), 14-15.
- ALONZO, D.S. and ORDINARIO, F.F. (1972) Tapping, collection and marketing practices of Manila elemi in Marinduque and Quezon provinces. The Philippine Lumberman, 18(Jun), 26-32. *ANON. (1972) Manila Elemi. FPRI Technical Note No. 122. 2pp. Laguna, the Philippines: Forest Products Research and Industries Development Commission.
- EVANS, B.R. (1991) A Variety Collection of Edible Nut Tree Crops in Solomon Islands [including the ngali nut]. Research Bulletin No. 8. Honiara, Solomon Islands: Ministry of Agriculture and Lands.
- GRIFFITHS, D.A. (1993) Canarium: pili nuts, Chinese olives and resin. West Australian Nut and Tree Crops Association Yearbook, 17, 32-45.
- GUENTHER, E. (1952) Oil of elemi. pp 357-360. In The Essential Oils, Vol. 4. New York: Van Nostrand Co.
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- OLIVEROZ-BELARDO, L. et al. (1985) Preliminary study on the essential oil of Canarium luzonicum (Blume) A. Gray as a possible supplement to diesel oil. Transactions of the National Academy of Science and Technology, 7, 219-232.
- SAWADOGO, M. et al. (1985) Oleoresin of Canarium schweinfurthii Engl. Annales Pharmaceutiques Francaises, 43(1), 89-96.
- TONGACAN, A.L. (1973) Manila elemi. Forpride Digest, 2(2), 6-7, 18.
- VILLANUEVA, M.A., TORRES, R.C., BASER, K.H.C., OZEK, T. and KURKCUOGLU, M.
(1993) The composition of Manila elemi oil. Flavour and Fragrance Journal, 8(1), 35-37. 106
