Isothermal-microwave pretreatment enhances the quality and oxidative stability of cold-pressed oil from short-term germinated sesame seeds

Enhancing the oxidative stability of cold-pressed sesame oil using green methods without high-temperature treatments remains challenging. Short-term germination is a common but limited solution. In this study, isothermal-microwave pretreatment (80 °C, 0-60 min) was applied to short-term germinated sesame seeds, followed by cold pressing. Results showed that moderate-duration pretreatments (10-30 min) yielded higher oil extraction rates (81.06%-82.22%) than the 0-min pretreatment (79.71%). Moreover, the β-tocopherol, γ-tocopherol, sesamolin, and total phenolics contents of the oils increased by 17.22%-35.14%, 10.90%-17.28%, 16.18%-25.60%, and 7.24%-26.19%, respectively, resulting in enhanced radical scavenging capacity and oxidative stability. This was because isothermal-microwave pretreatment promoted their migration into the oil bodies. Furthermore, the oil obtained from short-term germinated seeds pretreated with isothermal-microwave for 15 min also exhibited better frying stability than oil from seeds without pretreatment. Thus, this work presents a promising approach for producing high-quality cold-pressed oil with enhanced oxidative stability.