Encapsulación en liposomas de aceites esenciales para mejorar su retención en la elaboración de films de quitosano

Abstract

[EN] The effect of encapsulation of eugenol and cinnamon leaf essential oil (CLEO) in lecithin liposomes on the losses of these compounds during the chitosan film formation process, by casting, was evaluated. Film forming dispersions (FFD) with eugenol or CLEO (free compounds and from encapsulated compounds), and pure chitosan films and those containing lecithin liposomes were also obtained. Films with the 6 different formulations were characterized as to microstructure, optical and mechanical properties, water vapour barrier capacity and thermostability. Losses of eugenol in the active films were determined by solvent extraction and GC analysis. Encapsulation of eugenol or essential oil in lecithin liposomes lead to a 40- 50% retention of this compounds in the films, whereas only 1-2% was retained when compounds were incorporated by emulsification. Films with liposomes exhibit a lamellar structure which improved film extensibility and increased the water vapour barrier capacity. Liposomes modified optical properties of the films, reducing their gloss, increasing colour saturation and giving them redness. Encapsulation of volatile active compounds in liposomes appears as a good strategy to obtain active films with essential oils.

[ES] Se ha encapsulado aceite esencial de hoja de canela o eugenol en liposomas de lecitina para incorporarlos a films de quitosano como antimicrobianos/antioxidantes y mejorar su retención durante la etapa de formación del film por extensión y secado. Films control con los activos no encapsulados fueron también preparados para evaluar la mejora en la retención de compuestos activos. Los films obtenidos fueron caracterizados en la retención de compuestos activos y sus propiedades físicas y micro estructurales. La encapsulación mejoró en gran medida la retención de los aceites y la incorporación de las nano-capsulas afectó a la estructura y propiedades funcionales de los films