Toward sustainable food encapsulation: Eco-innovative and energy-efficient fabrication of phospholipid-stabilized nanoemulsions

The primary objective of the present venture is to fabricate food-grade phospholipid-stabilized oil-in-water nanoemulsion for the encapsulation of lignan-rich sesame oil. A large number of high-energy, high-cost instruments are available on the market; however, a combination of high-speed homogenization and the solvent evaporation method was successfully applied in this study to overcome the significant economic burden imposed by high-energy approaches. Furthermore, the challenge remained in circumventing synthetic surfactants and incorporating phospholipids as emulsifiers in the present work. The three nanoemulsion formulations, NEA, NEB, and NEC, were successfully fabricated using phospholipid and Tween 20 in 2:1, 1:1, and 1:2 ratios, respectively. The formulations were found to possess nano-droplet sizes, narrow polydispersity indices, and sufficient physical stability against creaming and phase separation. Phospholipid was shown to provide a thickened viscoelastic layer around the droplet, a highly negative surface potential and a favourable packing parameter. Engaging Tween 20 in adequate amounts was found to impart a steric-repulsive barrier to these phospholipid-stabilized formulations, which might help maintain stability across a wide range of pH and ionic strength. The physical stability against environmental stressors was highest in NEC owing to the substantial presence of Tween 20. On the contrary, NEA offered maximum protection against lipid peroxidation owing to the inherent antioxidant properties of phospholipids. Lipolysis in a simulated gastrointestinal environment was higher in the NEA formulation, indicating how interfacial composition alters enzyme kinetics under dynamic conditions. In this endeavour, selecting emulsifiers at the interface provides a platform that modulates physical and oxidative stability, as well as the in vitro digestion profile. The insights gained from this study yielded promising outcomes in the frontier area of nanodelivery.