Chemical composition and mineralogical residence of sesame oil from plants grown in different Yemeni environments

Sesame seeds collected in eight provinces of Yemen were used to prepare cold-pressed sesame oil over three consecutive years. After ascertaining the nutritional quality and compliance with official norm of each batch of oil, mineral composition was determined by ICP-OES. No major and significant variations were detected over three years indicating the high reproducibility of Yemeni sesame oil composition as a function of its geographic origin. Three physico-chemically distinct sub-groups were identified. A subgroup includes sesame oil from Al Bayda, Marib, Ibb, and Taiz; a second is constituted by sesame oil from Abyan, Shabwa, and Hadhramount while sesame oil from Hodeida presents its own specificity. Calcium content was between 3.02 and 9.66 mg/kg, this cation making up 50% of the total mineral content. The two other most abundant minerals were potassium (0.824-4.251 mg/kg) and magnesium (0.811-4.742 mg/kg). Potentially toxic metal (Cd, Pb, Cu, Sn and Zn) content was very low in all samples. Principal component analysis showed that Abyan oil presents a unique metal-content profile. The precise geographic origin of Yemeni sesame oil can be determined by element content analysis.