Antioxidant starch-based films with encapsulated eugenol. Application to sunflower oil preservation

[EN] Starch films containing eugenol, which was added to the film-forming dispersion in free form or encapsulated with different wall materials (whey protein or lecithin), were obtained by casting. The physical and the antioxidant properties of the films, the release kinetics of eugenol in different food simulants and their performance at preventing sunflower oil oxidation during storage were evaluated. Encapsulated eugenol modified the film microstructure, yielding less stretchable films with reduced water affinity, transparency and oxygen permeability as compared to films formulated with non-encapsulated eugenol. The addition of eugenol microcapsules containing oleic acid promoted the eugenol retention in the starch matrix during film formation and thus, these films exhibited the greatest antioxidant activity. Films developed with encapsulated eugenol powder containing lecithin and oleic acid were highly effective at preventing sunflower oil oxidation even throughout 53 days of storage at 30¿°C, maintaining low and almost constant values of peroxide index, conjugated dienes and trienes in comparison with the control samples.The authors acknowledge the financial support provided by the Spanish Ministerio de Educacion y Ciencia (Projects AGL2013-42989-R and AGL2016-76699-R). Author Emma Talon thanks the Universitat Politecnica de Valencia for a FPI Grant (99/2011). The authors also thank the services rendered by the Electron Microscopy Service of the UPV.Talón-Argente, E.; Vargas, M.; Chiralt, A.; González Martínez, MC. (2019). Antioxidant starch-based films with encapsulated eugenol. Application to sunflower oil preservation. LWT - Food Science and Technology. 113:1-10. https://doi.org/10.1016/j.lwt.2019.108290S11011

Laboratory antimicrobial activity of cinnamaldehyde and pomegranate-based polycaprolactone films

Polycaprolactone (PCL) was incorporated separately with cinnamaldehyde (CNMA), pomegranate methanolic extract (PME), freeze dried arils of pomegranate (FDAP), and seed flour of pomegranate (SF) to form antimicrobial films to be used for active food packaging. PCL–CNMA films completely inactivated growth of the artificially inoculated Escherichia coli and Staphylococcus aureus, whether at 5% or 10% concentrations (wt/wt of polymer), at all studied temperatures (4, 20, and 37 °C). PCL–PME films (10% wt/wt of polymer) delayed the growth of E. coli and S. aureus for up to 7 and 6 days, respectively, at 37 °C. Two-day delays in the growth of both bacteria were achieved with FDAP and SF films (10% wt/wt of polymer) at 20 °C. The release of CNMA was slower than the release of PME during film processing, as measured by Fourier transform infrared spectroscopy. Thus, CNMA and pomegranate-based films perhaps should be planned further for use in controlled release food packaging