Pentadesma butyracea (PROSEA)
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Introduction |
Pentadesma butyracea Sabine
- Family: Guttiferae
Synonyms
Pentadesma leucantha A. Chevalier.
Vernacular names
- African butter tree, tallow tree, kiasoso (trade name) (En). Arbre à beurre, beurre de lami (Fr).
Distribution
Native to West Africa, occurring from Guinea to Cameroon. It is cultivated elsewhere in tropical Africa and other tropical regions. In South-East Asia it was successfully grown in Singapore already around 1900.
Uses
The seeds contain a brown, edible, tasteless but pleasant-smelling fat ("butter") which is used for cooking and made into an unguent for skin and hair; it is applied to kill skin parasites such as lice and mites. It is suitable for making soap, candles and margarine and has the advantage that it does not turn rancid. The butter is also incorporated into several commercial balms used for massage. In cross-section the seeds are red and have been used to adulterate true kola ( Cola sp., they can easily be distinguished as the cotyledons do not differentiate as in kola). The fruits are edible when immature, becoming too hard upon ripening. Seeds also are edible when immature, turning bitter when ripe. The wood is fairly hard and heavy with a coarse structure and easy to work. There are almost no commercial applications, but poles are used for example as mine-props, for rough construction work, boat masts, canoes and fuel. The bark is used as fish poison in Ghana, a decoction as a purgative and an infusion in lotions to treat parasitic skin diseases. In Liberia the roots are used as chew-sticks and a decoction as a vermifuge.
Observations
Tree, up to 30 m tall and 75 cm in trunk diameter, sometimes with narrow buttresses or stilt roots; bole straight and slender, slash soft and brittle, light to bright red, the wound exuding a pale yellow latex; crown small with spreading branches which are slightly drooping at the end. Leaves opposite, simple, coriaceous; petiole up to 1 cm long; blade elliptical to obovate, 7-22 cm × 3-7 cm, base cuneate, margin entire, apex bluntly acute, shiny dark green, new flushes dark red. Inflorescence a panicle, up to 35 cm long, with few, large and showy, cream flowers; pedicel 2-3 cm long; sepals 5, unequal, 3-6 cm long, persistent; petals 5, ovate, 4-6 cm × 2-4 cm, imbricate; stamens numerous, grouped into 5 bundles; ovary sessile, style elongated, stigma with 5 linear lobes. Fruit a berry, ellipsoid to ovoid, up to 15 cm × 10 cm, pendulous, skin coriaceous, brown, containing 3-15 seeds embedded in yellow, greasy-juicy pulp. Seed angular, often pyramidal, 3-5 cm long, 2-3 cm thick, brown, red in cross-section, cotyledons not differentiated. Seedling with hypogeal germination. P. butyracea grows in primary and secondary forests, often in swamps. Flowering season coincides with the rainy season, main fruiting season in West Africa is October-March. P. butyracea flowers open and produce nectar at night; one of the pollinators is an African long-tongued bat ( Megaloglossus woermanni ). Although the fruits fall complete, the seeds are eaten by animals and natural regeneration is rather poor. Air-dried seed contains 30-40% fat which can be extracted by pounding and cooking. The major fatty acids are palmitic acid (1%), stearic acid (45%) and oleic acid (54%); the iodine value is 51. The presscake hardly contains carbohydrates and nitrogen; tannin and other substances make it unsuitable for feed or manure. Propagation is by seed and by cuttings and sapling growth is fast. Unless the butter becomes more important, P. butyracea will remain a curiosity in South-East Asia grown only in botanical gardens and parks.
Selected sources
2, 19, 20, 21, 132.
