Investigating the Oxidative Stability of Fish Oleogels Prepared with Carnauba Wax

Oleogels are semi-solid gels formed through the structuring of oils using organogelators under heating and cooling conditions. In this study, fish oil oleogels (FOs) were prepared by combining fish oil with varying concentrations of carnauba wax (4%, 6%, and 8%) through heating at 90 °C, homogenization, and subsequent cooling. All formulations successfully formed semi-solid gels at room temperature. As carnauba wax concentration increased, the oleogels exhibited a brighter yellow hue and firmer texture, indicating a more compact internal network structure between the wax and oil. The melting points of the oleogels ranged from 65 to 80 °C and increased proportionally with wax concentration, accompanied by enhanced viscoelastic properties. In vitro digestion simulations revealed that the 8% palm wax oleogel significantly delayed the release of fish oil in the gastric phase and facilitated its release in the intestinal environment, thereby potentially reducing the unpleasant fishy odor upon consumption. During storage at 45 °C, both bulk fish oil and FOs exhibited a continuous rise in peroxide value and p-anisidine value. Higher oxidative stability was exhibited by FO8%. These findings suggest that carnauba wax-structured fish oil oleogels can improve the physicochemical stability and sensory acceptance of fish oil-based products.