Improving the quality of multi-layer films based on furcellaran by immobilising active ingredients and impact assessment of the use of a new packaging material.

To improve the quality of multi-layer film, four-layer films based on furcellaran and active ingredients: gelatin hydrolysate, curcumin, capsaicin, montmorillonite and AgNPs, were produced in an innovative manner. The films were characterised by SEM and AFM analysis. Along with an increase in the concentration of active ingredients, the structure of the film becomes less homogeneous, which may affect the functional properties. The objective of the study was to analyse changes in the functional properties of the newly-obtained films and to verify their potential as packaging materials for fish products. With the increase in active ingredient concentration, water properties also improved, but there were no noticeable significant effects on mechanical properties. For antioxidant properties, the obtained values were within 1.04-2.74 mM Trolox/mg (FRAP) and 7.67-40.49% (DPPH). The obtained multi-layer films were examined with regard to the shelf-life of salmon. For this purpose, salmon fillets were packed in films having good antioxidant and functional properties. The films were effective in microorganism growth inhibition responsible for fillet spoilage during storage. The microorganism number in the active film-stored samples was lower by 0.13 log CFU/g on day 12 versus the control. However, film application did not retard lipid oxidation in the salmon fillets. Nonetheless, the films show great potential as active packaging materials, extending the shelf-life of the packed foods.