Kusum oil is a type of oil extracted from the seed of the Kusum tree (Schleichera oleosa). The plant, which is also commonly known as ceylon oak, lac tree, or Macassar oiltree, belongs to the Sapindaceae family. The schleichera family is named after J. C. Schleicher, a Swiss botanist, and the species name means "oily" or "rich in oil." The tree is native to India and Pakistan, but is also found in some parts of Southeast Asia.
Common names in Indian languages
- Common name: Ceylon oak, Lac tree, Gum lac tree
- Hindi: Kusum( कुसुम )
- Telugu: Posku, Busi,pusku,kosangi.
- Marathi:(कुसुम्ब) Kusumb
- Gujarati:( કોસુમ્બ) Kosumb
- Tamil: Kumbadiri
- Malayalam: Cottilai
- Kannada: Cakota
This tree grows naturally from the foothills of the Himalayas and the western Deccan to Sri Lanka and China. It was probably introduced to Malaysia and has naturalized in Indonesia. It grows in Bihar, Central and Southern parts of India. The tree occurs sporadically, seldom gregariously in dry, mixed deciduous forests. It grows in rocky, gravelly, or loamy, slightly acidic soil that is well drained. It is occasionally found in swampy locations, but it usually grows on rather dry soil, at low altitudes, but can be found at 900–1200 meters. The requirement of normal rain fall is 750–2800 mm. and ambient temperature of 35-47.5°C.
Schleichera oleosa (Kusum) is a large deciduous (nearly evergreen) tree with a comparatively short fluted trunk and a shade spreading crown. It is frost and drought hardy and is subject to damage by grazing. It produces root-suckers freely, and it has good cropping power. The wood is very hard and reddish brown. This tree is noted for its growth of new leaves that are bright red. In India the growth of these bright red leaves happens around March. The leaves are pinnate, with each leaf having 2-4 leaflets. The tree is host to Kusumi Lac, which is native to India.
Flowers: The flowers are tiny and hardly noticeable, occurring in short dense yellow clusters.
Fruit: The fruit is 2.5 to 3cm long - roughly the size of a small plum - and ovoid, 1-3 celled, and more or less abruptly tapering to a point, dry indehiscent.
Seed: The seed is 1.5cm long, smooth, brown, and enclosed in a succulent aril which has an acidic taste, and contains 25-38% oil and up to 22% protein. It is irregular or ellipsoidal in shape, slightly compressed, and has a thick brown seed coat on its surface. The moisture in the dried seed should be maintained around 4-6%. 
Kernel: The kernel is 16-20% of the dried fruit and 60-64% of the seed. It is 51-52% oil. The kernel is susceptible to fungal attack.
Collection of Seeds
Bunches of fruit are plucked by climbing the trees. Fruit pulp is removed by rubbing them in water, and letting them dry.
The oil contains oleic acid (2-3%), Stearic acid (2-6%), Gadoleic acid and arachidic acid as well as cyanogenic compounds, which must be removed for human consumption. Kusum oil is unusual, with just 37% of common glycerol esters. The oil also contains Linoleic acid (43-50%), Palmitic acid (5-8%), and hydrocyanic acid, which is poisonous and must also be removed prior to consumption. The oil is yellowish brown, semi-solid, with the faint odour of bitter almond. When allowed to settle, a light coloured solid fat separates. Kusum oil contains a cyanogenic compound in concentration of 0.03-0.05% as HCN. But the exact location of the cyanogenic compound in the oil or its nature has not been reported.
Table-Physical and chemical properties of kusum oil
|Moisture and insoluble impurities||0.25|
|Refractive Index at 50°C||4.4560-1.460|
|Specific gravityat 90°/30°C||0.865-0.869|
|Unsaponifiable matter% by Wt||3.0|
Table.2.Fatty acid composition of kusum oil
n-6 cisLinoleic acid(C18:2)||5.56
|n-7 Palmititoleic acid(C16:1)||1.80|
|n-9 cisOleic acid(C18:1)||2.83|
|n-6 TransLinoleic acid(C18:2)||49.69|
Uses of oil
- Kusum oil is used in hairdressing and to promote hair growth. The oil can also be used for cooking and lighting, and is used in traditional medicine systems for skin problems such as acne, itching, and burns. It is used as massage oil to relieve the pain of rheumatism.
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- Posted by abbas (2012-01-15). "Herbs-Treat And Taste: Kusum, Ceylon Oak, Or Macassar Oil Tree: Health Benefits And Uses Of Schleichera Oleosa". Herbs-treatandtaste.blogspot.in. Retrieved 2013-11-21.