Antioxidant films based on poly(lactic acid) incorporated with crude extract from Malpighia emarginata DC pomace for use in food packaging

Abstract The interest in natural antioxidants for the development of active food packaging is increasing, since lipid oxidation has a negative impact on food quality and people's living standards are changing. The aim of this work was to obtain Malpighia emarginata DC pomace extract (MEPE), as well as to develop poly(lactic acid) (PLA)‐based films with antioxidant activity, through the incorporation of MEPE. MEPE showed antioxidant activity through the DPPH and ABTS assays, 127.16 ± 9.70 μmol TEAC g −1 extract and 322.84 ± 19.38 μmol TEAC g −1 extract, respectively. The HPLC quantification revealed that quercetin and isorhamnetin were found at concentrations of 244.77 ± 8.42 and 707.20 ± 23.17 μg g −1 , respectively. The properties of the films were influenced by the presence of MEPE, which caused a plasticizing effect on the PLA film, reducing the tensile strength and Young's modulus and increasing the elongation at break and water vapour permeability. The antioxidant property test (DPPH and ABTS) of the films was shown to be improved with the addition of MEPE. Despite changes in the film properties, they have potential for application as active food packaging. This work showed the potential utilization of agriculture pomace to produce antioxidant additive and its application as antioxidant in active food packaging, since they showed excellent antioxidant activity in radical scavenging activity tests.