Enhancing the stability and quality of black seed oil during storage by incorporating Areca catechu L. powder as a natural antioxidant

Black seed oil (BSO) is known for its nutritional and therapeutic properties; however, it inherently has low oxidative stability, which necessitates the use of antioxidants. Due to growing concerns over the safety of synthetic antioxidants, natural alternatives have gained increasing attention. In this study, Areca catechu L. was incorporated into cold-pressed BSO at concentrations of 0% (control), 1.5%, 3%, 4.5%, and 6% (w/w). The oils were evaluated for quality attributes, peroxide value, acid value, chlorophyll, carotenoids, total phenolic content, and the Schaal test, on the day of preparation and at monthly intervals over a 90-day storage period. The results revealed that increasing levels of Areca catechu L. powder (BP) led to a reduction in acid value over time; after 90 days, the acid value of the control sample reached 3.5 mg KOH/g oil, compared to 2.4 mg KOH/g in the 6% treatment. Although peroxide values increased in all samples during storage, the sample containing 1.5% BP showed the lowest value (23 meq O₂/kg oil) on day 90, while the control reached the highest (28.7 meq O₂/kg). Carotenoid and total phenolic contents increased with BP concentration, whereas chlorophyll content decreased. On day 90, carotenoid and phenolic contents in the 6% sample were 0.53 mg/kg and 26.9 mg/kg, respectively, compared to 0.50 mg/kg and 6.00 mg/kg in the control. Conversely, chlorophyll content decreased from 11.5 mg/kg in the control to 6.1 mg/kg in the 6% treatment. These findings suggest that BP may contribute to improving the oxidative stability of BSO during storage under the experimental conditions investigated and may be proposed as a natural antioxidant for use in edible oils.