Investigating the novel use of rosehip extracts and seed oils in the production of alginate‑based edible films

Abstract

This study formulated biodegradable, edible films with sodium alginate and varying concentrations and a combination of seed oils (watermelon seed oil, sesame seed oil) and rosehip extract. In the present study, rosehip, sesame, and watermelon seed oils, which incorporated many bioactive compounds and are known to have antioxidant properties, were incorporated into edible films to improve the film properties due to the controlled release of the active substance and thus increase the storage time. The potential to form alginate-based edible films by incorporating this extract and seed oils into alginate-based films has not been thoroughly investigated. Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and mechanical, physical, thermal, and antioxidant properties characterized the edible film samples. The biodegradability by soil was also performed. Blending rosehip extract and its combination with seed oils significantly improved the films' antioxidant properties while reducing moisture content. In the study, the highest total phenolic content was recorded in the rosehip + sesame oil film (R2) sample (0.418 ± 0.015 mg GAE/g) and the lowest total phenolic content was recorded in the control sample (0.208 ± 0.014 mg GAE/g). Additionally, the highest % moisture value was recorded in the control sample (68.060 ± 0.530%), and the lowest % moisture value was recorded in the rosehip + sesame oil film (R2) sample (61.223 ± 0.881%). Watermelon seed oil blended film samples showed more homogeneity and had smooth surfaces compared to control samples. Alginate-based films incorporated with seed oils and rosehip extract may have caused color differences and whiteness index due to phenolic and bioactive compounds in their content. Soil degradation properties showed that the films were biodegradable. The elongation at break value of alginate-based films combined with rosehip extract and seed oils showed a significant increase compared to the control films. According to the results, alginate-based films combined with rosehip extract (films compounded with rosehip extract only and films compounded with rosehip and selected seed oils) improved film properties compared to control films. In addition, the incorporation of rosehip extract into the films improved the film properties compared to the films obtained using only seed oil. Based on the findings of this study, the use of rosehip extract, sesame, and watermelon seed oil in the development of composite biodegradable, edible films of sodium alginate could be used as a suitable alternative for edible food packaging.