|Small Scale Processing of Oilfruits and Oilseeds (GTZ, 1989, 100 p.)|
|1. Oil Plants and their Potential Use|
|1.2 The major oil plants|
Sesame, Sesamum indicum L, member of the family Pedaliaceae, is probably the most ancient oilseed used by man and originates from the Ethiopian area. It occurs as numerous species and is locally known under a variety of names, such as gingerly and til in India, sim-sim in Arab countries and East Africa and benniseed in Nigeria.
Figure 7: Sesame. (a) shoot top with flowers' (b) ripe capsules.
Source: S.Rehm, G. Espig, 1984, p. 1 02
Sesame is considered a crop of the tropics and subtropics and normally requires fairly hot conditions, with temperatures around 26°C encouraging rapid germination, initial growth and flower formation. In altitudes below 1250 m, sesame's main distribution is between 250 north and south of the equator, but it can be found further north in China, Russia and the USA and further south in Australia and South America. Optimal rainfall is 500 to 650 mm per year, but since the crop is reasonably drought resistant it can also be planted in relatively arid zones with annual rainfalls as low as 300 mm.
World production of sesame seed has been almost static for 20 years, at 2.4 million tons per year (see Table 1) and almost exclusively originates in developing countries. Major producers are China, India, Burma and Tanzania (in that order for 1985). A large proportion of the sesame seed harvested is, however, neither marketed nor exported but consumed by local producers and therefore often does not appear in statistics for home production. This is particularly true in Africa, where sesame is grown from north to south, but often in such small plots that it is impossible to calculate the total, large though it may be. It is estimated that only 10 % of the total production enters world trade in sesame seed, the largest exporters being China, the Sudan and Mexico, the largest importers Japan, USA and Hong Kong.
Although reaching as high as 2 tons per ha (in Yugoslavia), average yields are only 350 kg of seeds per ha, because sesame is mostly cultivated in arid regions with poor soils. The average seed composition is 45 to 50 % (highly valued) oil and between 19 to 25 % protein. Sesame seed is relatively sensitive to mechanical damage, and even minor damage at threshing can result in an immediate loss of the viability of the oil extraction process.