Synergistic effects and interactions among components in the surimi/κ-carrageenan/soybean oil system

When κ-carrageenan (KC), soybean oil, and surimi are mixed in appropriate proportions, they demonstrate significant synergistic effects. This study established a ternary system composed of surimi, KC, and soybean oil, exploring the synergistic effects and mechanisms among surimi, KC, and oil from multiple dimensions, including gel properties, rheological behavior, Raman spectroscopy, and microstructure. Gel strength analysis revealed that when the KC concentration was 4.0% (w/w), the surimi gel exhibited the highest gel strength. Moreover, the addition of an extra 5.0% oil further enhanced the gel strength. Rheological analysis indicated that the highest storage modulus (G') exhibited by the ternary system containing 5.0% oil is the result of synergistic effects among surimi, KC, and oil. Raman spectroscopy further uncovered the hydrogen bonding and electrostatic interactions between surimi proteins and KC, the hydrophobic interactions between surimi proteins and oil, and the hydrogen bonding between KC and oil. The results from scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) indicated that, compared to the pure surimi gel, the Surimi/KC/Oil ternary gel containing 5.0% oil exhibits a more compact and uniform network structure, attributable to the filling effect of KC and oil on the gel network. These results suggest that the synergistic effect is induced by the physicochemical interactions among surimi, KC and oil in appropriate proportions.