Modulating the interfacial structure of peanut oil body emulsions through different extraction methods: implications for curcumin delivery

This study investigated the microstructure, interfacial properties, and curcumin (Cur) delivery performance of peanut oil body emulsions (OBEs) prepared via aqueous, enzyme-assisted, heat-treated, water-washed, and NaHCO 3 methods. Peanut OBEs extracted by enzyme-assisted (E-OBE) and heat-treated (H-OBE) methods exhibited loose three-dimensional network structures with high protein contents (1.56% and 1.65%) and apparent viscosity. NaHCO 3 -extracted OBE (N-OBE) showed a tightly packed structure featuring high lipid content (75.56%), elevated storage modulus, and the smallest particle size (3.91 μm). Exogenous proteins-rich E-OBE and H-OBE (lipoxygenase, Ara h1, arachin, and conarachin) and oleosin-rich N-OBE achieved higher Cur encapsulation efficiencies (EEs 87.38%, 84.33%, 86.35%) than aqueous-extracted OBE (62.10%). NaHCO 3 method promoted β-sheet structure formation (15.18%) in oleosins, enhancing hydrophobic interactions between the lipid or phospholipid and oleosins. Furthermore, N-OBE demonstrated superior environmental stress resistance (77.94% retention after 48-h UV irradiation, 96.06% and 93.57% retention after 2-h heating at 60 °C and 90 °C, respectively) and high Cur bioaccessibility (32.40%). These findings provided valuable theoretical foundations for developing peanut OBE-based delivery systems. • Extraction methods affected the interface layer of peanut oil body emulsions (OBEs). • Enzyme-assisted extraction and thermal extracted OBEs had high apparent viscosity. • NaHCO 3 extracted OBE had small size and high encapsulation efficiency of curcumin. • NaHCO 3 extracted OBE effectively improved stability and bioaccessibility of curcumin.