Enhancing canola oil's shelf life with nano-encapsulated Mentha aquatica extract for optimal antioxidant performance

Incorporation of antioxidants, such as phenolic compounds into edible oils has limitations such as rapid release of phenolic compounds, low solubility, low penetration, low accessibility, and rapid degradation by environmental compounds. To solve this problem, the nano-encapsulation process is offering promising opportunities. In this research, for the first time, the phenolic extract of Mentha aquatica was nano-encapsulated in nano-emulsions coated with chitosan, Lepidium perfoliatum gum (LPG), and complex of chitosan and LPG (CCL) (1:1 ratio). Based on various tests (particle size measurement, zeta-potential, polydispersity index, encapsulation efficiency index, and intensity curve), the LPG coating was the most optimum option for nano-encapsulation compared to the other coatings. Thus, the LPG-assisted nano-encapsulated phenolic extract of M. aquatica was used to improve the oxidative stability of canola oil at three concentrations (100, 200, and 300 ppm). The results of peroxide value and anisidine index tests (as initial and secondary oxidation indicators, respectively) showed that the nano-encapsulation improved the antioxidant effect of M. aquatica when compared with free extract in canola oil. In a comparative approach, the best sample was obtained from the LPG-assisted nano-encapsulated extract (200 ppm) due to the release of more phenolic compounds. The findings from this study showcase how nano-encapsulation enhances the efficacy of antioxidants in edible oils.