Fatty Acid Profiles of White Sesame Seeds from the Different Cultivation Areas of Ethiopia

Abstract

Sesame is the second important export commodity of Ethiopia after coffee. The white sesame seeds (Sesamum indicum L.) from the main production areas of Ethiopia have not been studied comprehensibly for their chemical compositions. Hence, this study aimed to assess the geographical origin variations in the fatty acids composition of white sesame seeds. For this, fifty three white sesame seed samples from the five major producing areas (Humera, Metema, West Armachiho, Wolkayiet, Tach Armachiho) were analyzed for their fatty acid compositions using gas chromatography coupled with mass spectrometry (GC MS). Nine different fatty acids were detected in all of the samples. The sesame seeds were rich in the essential fatty acids, linoleic acid and oleic acid, which were the most abundant fatty acids in the seeds with percentage compositions in the range 35.3‒48.3% and 29.8‒38.2%, respectively, across the different samples. These two fatty acids together accounted for 72.0‒78.8% of the total fatty acids in the samples, whereas 19.8‒22.0% was accounted jointly by palmitic acid and stearic acid while trace levels (all together 1.34‒2.32%) were palmitoleic acid, margaric acid, gadoleic acid, arachidic acid, and behenic acid. The seed oils showed high unsaturated-to-saturated fatty acid ratio in the range of 2.98‒3.70, which is high enough to satisfy most dietary guidelines. The oleic acid to linoleic acid ratio of the seed oils were in the range of 0.80–0.97, where the highest was found in seeds from Humera. Regarding the individual fatty acids, a significant variation (p < 0.05) among production areas was observed only for palmitic acid and palmitoleic acid, where the highest concentrations were found in seeds from Humera (14.9±1.5% palmitic acid and 0.25±0.04% palmitoleic acid).