Novel Poly(butylene succinate-dilinoleic succinate) Films in Packaging Systems for Fresh Cut Chicory

Ready-to-eat products, such as mixed-cut leafy vegetables, require packaging that provides adequate mechanical protection, a barrier against UV radiation, gases, and water vapor, as well as microbiological safety. In this study, thin films made of polybutylene succinate (PBS) and poly (butylene succinate-dilinoleic succinate) (PBS-DLS) copolyester were prepared by casting a film-forming solution onto a glass plate and spreading it with a roller. These films were compared to commercial thin films made of oriented polypropylene (OPP). OPP films exhibited ten times higher tensile strength than PBS films (104.36 ± 10.03 MPa for OPP, 10.96 ± 0.68 MPa for PBS, and 6.36 ± 0.62 MPa for PBS-DLS). Incorporation of co-monomeric units of dilinoleic succinate (DLS) into PBS structure significantly improved elongation at break, increasing from 38.16% ± 12.36% for PBS to 132.30% ± 25.08% for PBS-DLS. However, commercial OPP had the highest elongation at break, reaching 231.84% ± 20.30%. OPP films exhibited the highest transparency in the visible light range but also in the UV range. In contrast, PBS and PBS-DLS films provided better UV radiation blocking. The films were used to create sachets by heat sealing, into which freshly cut chicory leaves were placed. The packaged product was stored under refrigerated conditions for 48 h and 120 h. While OPP and PBS-DLS films provided good protection against moisture loss in chicory, leaves packed in PBS sachets lost significant weight during storage. The packaged product contained considerable microbial contamination, but the type of packaging did not influence its reduction or increase. Ultimately, the PBS-DLS copolymer exhibited higher elongation at break and greater water vapor barrier properties than PBS. Protection against moisture loss in packaged chicory for PBS-DLS packaging was similar to that for commercial OPP. Despite their weaker mechanical properties, PBS-DLS films appear to be a promising alternative to OPP films for packaging fresh food products.