Studies on Egyptian sesame seeds (Sesamum indicum L.) and its products 1-physicochemical analysis and phenolic acids of roasted Egyptian sesame seeds (Sesamum indicum L.).

The effect of roasting on physical characteristics, chemical composition and phenolic acids of 2 sesame seeds varieties Giza 32 (G 32) and Shandawil 3 (Sh 3) were studied. The results showed that the roasted seeds contained 0.20-3.06% moisture, 18.92-23.18% crude protein, 3.01-4.38% ash, 6.75-7.34% crude fiber, 56.49-59.97% crude oil and 4.33-11.59% total carbohydrates. The oil from roasted sesame seeds was found to contain high levels of unsaturated fatty acids, especially oleic (up to 39%) and linoleic (up to 42%). Sesamum indicum L. oil can be classified in the oleic-linoleic acid group. The dominant saturated acids were palmitic (up to 7%) and stearic (up to 5%). Phenolic acids were identified by high performance liquid chromatography (HPLC). Ellagic acid was the most predominant amongst the sixteen phenolic acids identified in sesame seeds samples. Gallic acid, vanillic acid and benzoic acid increased with roasting. Our study has demonstrated that roasted sesame seeds gave the most desirable quality of raw sesame seeds with respect to phenolic content and fatty acid composition. Sesame (Sesamum indicum. L., synonymous with world, higher in quantity than olive oil and safflower oil Sesamum orientale L.), also known as benniseed (Africa), (6). Sesame seed contains high levels of fat and protein. benne (Southern United States), gingelly (India), gengelin The chemical composition of sesame seed varies with the (Brazil), sim-sim, semsem (Hebrew) and tila (Sanskrit), variety, origin, color and size of the seed. The fat content is the world's oldest oil crop. It belongs to the Tubiflorae of sesame seed is around 50% whereas the protein order, Pedaliaceae family, which comprises of 16 genera content is around 25%. Sesame seed contains about 5% and some 60 species. There are 37 species under the of ash, whereas the fiber and carbohydrate contents Sesamum genus. Among the 37 species, only Sesamum show large variation (7). The chemical composition of indicum is widely cultivated. As most of the wild species sesame shows that the seed is an important source of oil of sesame were found in Africa, it is generally believed (44-58%), protein (18-25%), total carbohydrates (~13.5%) that sesame originated in Africa. India may also be the and ash (~5%) (8-15). origin of some species (S. capense, S. prostratum and Sesame seed has about 17% seed weight as hull, S. schenckii) of sesame. The sesame species in the which is high in oxalic acid (2~3%), calcium and crude Middle East are similar to Africa; they are believed to be fiber. Oxalic a cid could complex with calcium and spread from Africa via Egypt (1, 2, 3). The color varies reduces its bioavailability; indigestible fiber would from white, yellow, gray, red, brown, to black. The weight reduce the digestibility of protein (7, 16). Sesame seed is of 1000 seeds is around 2.5 to 3.5 g. The oil drops are a rich source of edible oil. It contains more oil than the located in the cotyledon. It is generally believed that the major oilseeds, such as soybean, rapeseed-canola, light-colored seeds with thin coats are higher in quality sunflower seed and cotton seed. Oil content of sesame and oil content than the dark-colored seeds. Each year, seed varies with the variety of sesame; it may range from the world consumes close to 120 million MT of edible fats 28% to 59%. In general, the cultivated seed has around and oils (4, 5).