Encapsulation of bioactive compounds from food processing waste: rosehip seed model

In this thesis, the recovery of bioactive compounds from industrial waste defatted rosehip (Rosa canina L.) seeds and their encapsulation into nanofibers by the electrospinning were investigated. Extracts were obtained from defatted rosehip seed powder using ultrasound-assisted extraction, and these compounds were incorporated into polyvinyl alcohol-based spinning solutions to produce nanofibers. The antioxidant activity of the spinning solution was determined by ABTS and DPPH assays, while the total phenolic content was measured using the Folin-Ciocalteu method. The extract exhibited an ABTS value of 553.28±32.8 mg Trolox/L, a DPPH value of 1027.30±30.1 mg Trolox/L, and a total phenolic content of 46.28±0.46 mg GAE/L. Response Surface Methodology was employed to optimize the electrospinning parameters. The optimum conditions were determined as a collector distance of 10 cm, an applied voltage of 24.36 kV, and a feed rate of 1.0 mL/h. FT-IR analysis revealed characteristic band shifts in extract-loaded nanofibers, indicating successful incorporation of bioactive compounds into the polymer matrix. SEM analysis showed that the average fiber diameters of the control samples (CNF-1 and CNF-2) were 270±56 nm and 338±76 nm, respectively, while the extract-loaded samples (RNF-1 and RNF-2) exhibited average fiber diameters of 306±76 nm and 348±86 nm. TGA and DSC analyses demonstrated multi-step degradation behavior under a nitrogen atmosphere up to 600°C. The results indicate that rosehip seed extract was successfully encapsulated into electrospun nanofibers, highlighting the potential of food industry waste as a source of value-added functional components.