Comparison Studies on Antioxidant Properties of Black Sesame Seed (<i>Sesamum indicum L.</i>) Extracts Prepared by Thermal Processing Methods

Abstract

The effects of thermal processing methods on antioxidant properties (DPPH, ABTS and FRAP) of black sesame seeds (BSS) were investigated. In this study, all samples were thermally processed by steaming, roasting and microwaving, and the effects on the levels of total phenolic content (TPC), tannins content (TC) and total flavonoid content (TFC) were also studied. The thermal processes applied in the present study were: steaming (80 kPa for 15 min and 30 min), roasting (160 °C for 5 min and 10 min) and microwaving (4 min and 8 min). The results showed that the steaming process led to significant (p oC for 10min. Despite the higher level of total phenolics and tannins content observed in roasted sample, roasted BSS extract showed the lowest antioxidant activity in DPPH (15.2%), ABTS (45.6%) and FRAP (110.0 10-3mM Fe2+ /100 g). Steamed BSS at 80 kPa for 30 min exhibited the highest antioxidant activity, suggesting that steaming is the preferred thermal processing method to get better health-related quality of BSS products.