Steam explosion combined with subcritical extraction: A novel strategy for efficiently enhancing the content of (Z)-Lycopenes and comprehensive nutritional quality in tomato seed oil.

Lycopene is a distinctive nutrient found in tomato seed oil. In comparison to (all-E)-lycopene, the (Z)-lycopenes provided superior antioxidant activity and bioavailability. This study investigated steam explosion (SE), microwave (MW), and infrared (IR) pretreatments combined with subcritical extraction on tomato seed oil quality specially lycopene. (5Z)-(9Z)- and (13Z)-lycopene as the main (Z)-lycopenes were identified by spectral signatures. MW and IR pretreatments resulted in total (Z)-lycopene proportions (26.96% and 25.77%, respectively) than the untreated control (29.74%), while SE pretreatment significantly increased the total (Z)-lycopene content to 43.06%. Moreover, SE pretreatment enhanced other key nutritional indicators: total phytosterols rose from 7288.03 to 8058.57 mg/kg, α- and γ-tocopherol contents increased from 93.98 to 128.57 mg/kg and from 856.24 to 997.61 mg/kg, respectively, and total phenolics increased from 44.33 to 179.83 mg/kg. SE at 1.0 MPa gives strongly correlated with overall nutritional quality via principal component analysis. This strategy provided a considerable potential for the production of high-value, nutrient-rich tomato seed oil.