Effects of Selected Plant Extracts on the Quality and Functional Properties of Gelatin and Furcellaran-Based Double-Layer Films

Abstract In this study, for the first time, double-layer films based on furcellaran and gelatin were obtained, in which the 1st layer of furcellaran was enriched with various plant extracts. The aim of this work was to improve the composition of the developed innovative packaging material by using two layers of biopolymer complexes and analysing the composites to determine the effect of different model plant extracts on the physicochemical properties of the double-layered materials. Furthermore, the hypothesis that positron a nnihilation lifetime spectroscopy (PALS) could be correlated with gas barrier properties was verified. The addition of plant extracts significantly influenced the physicochemical parameters of the obtained double-layered materials. The lowest solubility was noted in films with the addition of garlic extract (58.40%) and black pepper extract (59.26%) which also had the lowest water content (8.88%). The film with garlic extract also had the lowest oxygen transfer rate (OTR) value after 6 months of storage which is consistent with PALS. The presented data suggest the possibility of correlating PALS results with the gas barrier properties. Tests carried out using this method will facilitate the selection of new potential ingredients when designing packaging materials based on biopolymers, thus, making it possible to obtain new-generation matrices.