Natural-Origin Edible Gels as Delivery Systems for Green Tea Extract: Formulation, Physicochemical, and...

Natural-origin edible gels are gaining attention as innovative carriers for bioactive compounds, offering consumer-friendly formats and potential to enhance stability and bioavailability. This study aimed to develop and characterize edible gels incorporating Camellia sinensis (L.) Kuntze extract using different plant-based gelling agents, including whole flaxseeds, ground flaxseeds, medium-size oatmeal, and coarse oatmeal. The physical properties of the gels were evaluated by rheological (flow curve) and pH studies. The phytochemical composition of the green tea extract and gels with this extract and the main phenolic compounds, including catechins, gallic acid, and caffeine, were evaluated by high-performance liquid chromatography. The biopharmaceutical properties of the prepared gels were evaluated by dissolution testing. Rheological analysis revealed that oat-based gels exhibited higher viscosity (up to 24.33 Pa·s) compared to flaxseed-based gels. Despite differences in consistency, no statistically significant differences were found in total phenolic release among gel formulations (p > 0.05), except for epigallocatechin, which showed significantly higher release from coarse oatmeal gels (p > 0.05). The findings suggest that both flaxseed- and oatmeal-based gels are promising natural carriers for green tea phytochemicals, offering standardized dosing and potential cognitive health benefits. Further studies are warranted to assess the in vivo bioavailability and long-term stability of these formulations.