In this study, antioxidant food-packaging materials were developed by the incorporation of merken, an aboriginal Chilean spice, into a biodegradable polymer matrix, poly(lactic acid). Antioxidant activity assays and the phenolic content of merken showed interesting results compared to other condiments, such as oregano and parsley. Active materials with merken at 3 and 5 wt % were successfully obtained by extrusion. Chromatographic analysis revealed the chemical composition of merken, and its active material was based on interesting flavonoids and organic acids, such as catechin, myricetin, and gallic and ellagic acids. Scanning electron micrographs showed that the merken particles accumulated in aggregates; this resulted in an increase in the permeability values and a reduction in the crystallinity and mechanical properties of the polymer matrix. Nevertheless, these materials presented interesting antioxidant activities as radical scavengers on aqueous food simulants. The kinetics of release was dependent on the type of food and the nominal content of merken in the films. (C) 2017 Wiley Periodicals, Inc.