This study focuses on the development of polyvinyl alcohol-chitosan-tragacanth gum composite films enriched with rosehip extract and seed oil for the packaging of active foods. The films were tested for their antioxidant activity, transparency, biodegradability, water vapor permeability and effectiveness in preserving sweet cherries under seasonal high temperature conditions. The addition of tragacanth, rosehip extract and rosehip seed oil significantly influenced the mechanical properties by increasing elongation at break and tensile strength. Films enriched with rosehip seed oil effectively reduced weight loss and preserved the sensory properties of the cherries, while films based on rosehip extract exhibited superior antioxidant properties with increased free radical scavenging activity. Biodegradability tests showed that all films degraded under soil conditions, with the rate of degradation depending on the concentration of tragacanth gum. The water vapor permeability results showed that the addition of rosehip extract and seed oil significantly reduced the water vapor permeability and improved the barrier properties of the films. Preservation tests showed that these films minimized titratable acidity, oxidative stress and moisture loss, effectively extending the shelf life of sweet cherries under highly stressful conditions. These results highlight the potential of rosehip-enriched biopolymer films as a sustainable and environmentally friendly packaging alternative to extend the shelf life of perishable fruits.

The objective of the present work was to investigate the effect of CMC biopolymer on the physicochemical, mechanical, thermal, barrier, and biodegradation properties of PVA-based films. The polymeric films were developed using solution casting method, incorporating CMC at concentrations ranging from 0.5 to 1.5%. With the addition of CMC, the tensile strength (TS) of the hybrid films was reduced from 1.40 +/- 0.02 MPa to 1.99 +/- 0.02 MPa. However, there was a significant improvement in the elongation at break (EAB) up to 49.29% compared to PVA film. The addition of CMC resulted in substantial improvements in water vapor permeability (WVP) and moisture retention capacity (MRC), showcasing a 38.73% improvement in WVP and a satisfactory MRC of 78.374% at 0.5% CMC concentration. The hybrid films also exhibit enhanced light absorbance at UV wavelength with opacity ranging from 0.301 to 1.413. TGA analysis showed a notable enhancement in the decomposition temperature of the hybrid PVA/CMC films, resulting in reduced mass loss compared to the PVA film. FTIR spectra confirmed that blending CMC with PVA led to the formation of strong hydrogen bonds within the polymer blend, significantly affecting the intermolecular forces inside the cellulose matrix. Moreover, with the addition of CMC, the degradation rate of the PVA/CMC film was increased approximately to 40% on the 30th day of soil burial. The films also exhibit effective microbial degradation against Pseudomonas putida and Bacillus subtilis bacteria strains as compared to commercial plastics. Overall, the obtained results validate the use of CMC biopolymer for blending of single polymer system as well as scaling down the extensive use of petroleum-based polymers in the field of packaging.