Characterisation of flavourous sesame oil obtained from microwaved sesame seed by subcritical propane extraction

This study developed a novel and green method to produce fragrant sesame oil using microwaves and subcritical extraction (SBE). Sesame seeds were microwaved at 540 W for 0-9 min before subcritical propane extraction at 40 °C and 0.5 MPa. SBE caused less deformation to the cellular microstructure of sesame cotyledons while dramatically improving oil yield (96.7-97.1 %) compared to screw processing (SP) (53.1-58.6 %). SBE improved extraction rates for γ-tocopherol (381.1-454.9 μg/g) and sesame lignans (917.9-970.4 mg/100 g) in sesame oil compared to SP (360.1-443.8 μg/g and 872.8-916.8 mg/100 g, respectively). Microwaves generated aroma-active heterocyclics and phenolics faster than hot-air roasting in sesame oil with a better sensory profile. SBE had a higher extraction rate for aroma-active terpenes, alcohols, and esters while reducing the concentrations of carcinogenic PAHs and HCAs in sesame oil. The novel combination process of microwaves and subcritical extraction is promising in producing fragrant sesame oil with superior qualities.