Abstract
This study investigated the mechanisms underlying the influence of droplet size and emulsifier wettability on gel properties when oil-in-water (O/W) emulsions serve as fillers in myofibrillar protein (MP) gels. Pickering emulsions with varying droplet sizes were prepared using soybean protein isolate (SPI) and SPI-curcumin nanoparticles, then used to construct composite gels. Findings showed that decreased droplet size and increased emulsifier surface hydrophobicity enhanced hydrophobic interactions in the gel, increasing the β-sheet content of MP molecules. Upon the introduction of SPI-Cur-NPs stabilized nanoemulsion (SCNE), the hydrophobic force in the gel was approximately 2.6-fold more remarkable than that of the control, and the β-sheet content increased to 16.51 %. This resulted in a denser mesh framework and more uniform oil droplet distribution, increasing the hardness value from 26.993 g to 41.847 g. Moreover, SCNE addition improved gel antioxidant properties, reducing carbonyl and peroxide levels to 31.82 % and 24.15 % of the control, respectively. These findings offer insights for improving MP-based gel products.