Eugenol-loaded LLDPE films with antioxidant activity by supercriticalcarbon dioxide impregnation

MARÍA LAURA GOÑI; NICOLÁS GAÑÁN; MIRIAM STRUMIA; RAQUEL MATINI

JOURNAL OF SUPERCRITICAL FLUIDS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 p. 28 - 35

0896-8446

tIn this work, linear low density polyethylene (LLDPE) films were impregnated with eugenol using super-critical CO2impregnation, as a strategy for obtaining a loaded material to be potentially applied in activefood packaging. Eugenol, the main component of clove oil, is well known as a natural antioxidant andantimicrobial agent. Impregnation runs were performed in a lab-scale high pressure stirred cell at 45◦Cduring 4 h, and the effect of pressure (10, 12 and 15 MPa) and depressurization rate (0.5, 1 and 5 MPa/min)on impregnation yield was evaluated. Yields of 1?6% (w/w) were achieved, with higher values at lowdepressurization rate. Film samples were characterized by infra-red spectroscopy (FTIR) and differen-tial scanning calorimetry (DSC). FTIR analysis suggested that the distribution of eugenol in the films isnot totally homogeneous. DSC revealed a decrease in the crystallinity degree in the impregnated sam-ples as well as in films subjected to pressurization with CO2but not loaded with eugenol. Changes inmechanical properties were also investigated in a texturometer. A decrease of LLDPE Young modulusand ductility was observed after high pressure impregnation, although tensile strength was not signifi-cantly affected. Finally, the antioxidant activity of the eugenol-loaded films was assessed via the DPPHinhibition test.