Process intensification for activated clay bleaching of sea buckthorn pulp oil

An optimized activated clay (ACL) bleaching process was developed for ‘Shenqiuhong’ sea buckthorn pulp oil (SPO). Among the four tested adsorbents, ACL showed the highest chlorophyll removal efficiency. Single-factor experiments and response surface methodology were applied to optimize key variables (dosage, temperature, and time). The optimal conditions (6.9% ACL, 73 °C, 36 min) reduced chlorophyll by 84.6%, while maintaining the fatty acid profile and improving visual quality. Levels of peroxide, moisture, phosphorus, and heavy metals were also significantly decreased. Although partial loss of phenolics and flavonoids occurred, the oil preserved considerable bioactivity. To our knowledge, this is the first comprehensive optimization of ACL bleaching for SPO, demonstrating a scalable method to improve oil quality and stability, and providing a technical reference for its use in functional foods, nutraceuticals, and cosmetics. • Optimized ACL bleaching reduced chlorophyll in SPO by over 84%. • Bleaching improved oil brightness while preserving fatty acid profile. • Heavy metals and phosphorus were significantly reduced by ACL treatment. • Bioactive retention confirms effectiveness of the method for functional oil refining.