Physio-mechanical properties of an active chitosan film incorporated with montmorillonite and natural antioxidants extracted from pomegranate rind.

An active film was prepared from chitosan incorporated with montmorillonite (MMT) and pomegranate rind powder extract (PRP). The effect of MMT (1 %, 3 %, and 5 % w/w chitosan) and PRP (1 %, 1.5 %, and 2 % w/v chitosan) on the physical, mechanical and antioxidant properties of the chitosan-based films was studied. Fourier transform infrared (FTIR) spectra revealed that good interactions occurred between functional groups of chitosan with MMT or with PRP. The results showed that the water vapor barrier property of the films was significantly improved by incorporation of MMT and PRP (p < 0.05). When compared to pure chitosan film, the WVP of M3P2 film (Chitosan/3 % MMT/2 % PRP) decreased by 25.2 %. Tensile strength of the films was affected by the addition of MMT and PRP. However, percent elongation at break was not significantly changed by addition of PRP. The film incorporated with 3 % MMT and 2 % PRP that contained the highest amount of total phenolic (15.2 mg GAE/g DW), was found to be the most active radical scavenger. These results suggest that chitosan films containing MMT and PRP can be used for development of active food packaging materials.