Composition and quality characteristics of sesame seed (Sesamum indicum) oil roasted at different temperatures in an electric oven

Abstract

AbstractThe quality characteristics of sesame oils prepared at different roasting temperatures (120–250°C) from sesame seeds using a home electric oven were compared with an unroasted oil sample: only minor increases (P < 0.05) in characteristics, such as acid value, peroxide value, anisidine value and thiobarbituric acid value, of sesame oils occurred in relation to increasing roasting temperature between 120 and 180°C, but colour increase was more pronounced. In the oil prepared using a 250°C roasting temperature, the glycolipid content per 1000 seeds increased markedly (262.9 mg) compared with unroasted oil (6.9 mg) and phospholipids were no longer detectable. The fatty acid content of the oil was reduced, reflecting an increase in glycolipid content and triglyceride oxidation/polymerisation when the roasting temperature was over 220°C but fatty acid composition was unchanged. The amounts of γ‐tocopherol and sesamolin still remained over 900 g kg−1 of the original level after roasting at 180°C, but were almost depleted at 250°C Sesame oil prepared using a 180°C roasting temperature had the best flavour score when compared with the other samples.