Antioxidant activity of coatings containing eugenol for flexible aluminium foils to preserve food shelf-life

Active food packaging is an innovative system that avoids food deterioration ensuring quality, safety and shelf life extension of food. Herein, two novel eugenol vinyl-based resins were used for coating flexible aluminium foils with potential packaging applications. Coatings were prepared with single eugenol or loaded eugenol in Santa Barbara Amorphous15 (SBA-15) mesoporous silica nanoparticles, and their antioxidant activity was investigated by DPPH, ABTS, ORAC, TBARS assays and by the hydroxyl free radicals' generator method with HPLC analysis. Antioxidant activity was also evaluated exposing the coatings to various food simulants. Both coatings revealed adequate antioxidant capacity when exposed to fatty food simulants and to vapour phase hydroxyl free radicals (scavenging > 50%). The incorporation of eugenol in SBA-15 reduced its release to 65%, promoting eugenol beneficial antioxidant effects over time. The release of eugenol from the coatings into food simulants is not required for the activity of free radical scavenging.