New active packaging based on encapsulated carvacrol, with emphasis on its odour masking strategies
New active polyethylene packaging with both antioxidant and antimicrobial properties was designed and produced using three different concentrations of encapsulated carvacrol. Films containing 10%, 20% and 30% of active capsules showed strong antioxidant activity as hydroxyl (OH·) radical scavengers, while only films containing 30% capsules showed anti-Salmonella enterica activity. Storage of active packaging rolls in sealed aluminium bags maintained both the antioxidant and antimicrobial properties of the films for up to 9 months. Two strategies were used to control or eliminate the strong odour of the developed packaging materials: odour masking spray and multilayer packaging. Migration tests were carried out to assess the safety of packaging. The most successful strategy was the development of two active multilayer packaging materials (polyethylene terephthalate (PET)/adhesive/active low density polyethylene (LDPE) with 10% capsules and aluminium/adhesive/active LDPE with 10% capsules) which reduced the oxidation of packaged crisps stored at 60 °C for 30 days by up to 45%, measured as malonaldehyde using the TBARS assay. In addition, the packaging materials did not affect the organoleptic properties of the stored crisps as determined by sensory analysis. These results show that this novel bifunctional (antioxidant and antimicrobial) active packaging can protect fatty foods from oxidation processes while preserving their organoleptic properties.