Structural characterization and oxidative stability of black cumin oil oleogels prepared with natural waxes

In this study, black cumin oil (BCO) oleogel was produced using natural waxes (beeswax: BW, sunflower wax: SFW, and carnauba wax: CW) to offer a healthy alternative to shortening. Oiling-off was observed only in the BW oleogel (3.88 ± 0.02%). The CW oleogel had the lowest Ea (354.82 kJ/mol), indicating greater resistance to thermal degradation. The highest G′ and G″ were observed in the CW oleogel, while the lowest was observed in the BW oleogel. All oleogel samples displayed weak gel properties (tan δ > 0.1), but the lowest tan δ value belonged to the CW oleogel (0.12). After 4 weeks of storage, the peroxide values of the oleogels were lower than those of bulk oil (p <.05). Finally, the oxidation results showed that the BCO structuring by the waxes effectively protected it from oxidation over eight weeks of storage. Novelty impact statement: The most important innovation of the present study was to investigate the effect of BCO oleogelation on the stability of thymoquinone, the main phenolic compound of BCO. The BCO oleogels had higher thymoquinone content during the first half of the storage period compared with bulk BCO, showing that the oleogel network provides a protective effect against oxidation and thermal degradation.