Application possibilities of triple-layer furcellaran film with hazelnut oil microemulsion for packing cod liver oil

Abstract

Triple-layer films based on furcellaran were successfully produced, where the middle layer was enriched with a hazelnut oil microemulsion. SEM images showed good embedding of the emulsion in the furcellaran layer. The addition of microemulsions significantly decreased the thermal and mechanical properties of the films, where the tensile strength values decreased, while the elasticity values of the film were improved. The presence of the emulsion increased the hydrophilicity of the film surface. The developed films in the form of sachets were used for packaging and storing cod liver oil. Fish oil was stored in refrigerated conditions without access to light and at room temperature (22 °C ± 1 °C) with access to light for 3 months. The acid (AV), iodine (IV) and peroxide values (PV), as well as the profile of fatty acids, were determined for the cod liver oil samples. It was shown that the cod liver oil samples had a similar value of the acid number during storage, however, over time, the IV and PV values increased statistically significantly, which indicates the ongoing process of fat rancidity. Furthermore, 23 compounds were identified in the fatty acid profile. It was shown that the profile of fatty acids in the stored fish oil changed, and the direction of these changes varied and generally, significantly depended on the film type and conditions in which the fat was stored. This study shows the possibility to obtain biodegradable packaging based on furcellaran enriched with a hazelnut oil microemulsion but also underline how important it is to check the presented packaging material in terms of its potential application.