Evaluation of mechanical, antimicrobial, and antioxidant properties of vanillic acid induced chitosan/poly (vinyl alcohol) active films to prolong the shelf life of green chilli.

Vanillic acid incorporated chitosan/poly(vinyl alcohol) active films were prepared by employing a cost-effective
solvent casting technique. FTIR investigation validated the intermolecular interaction and formation of Schiff's
base (C=N) between functional groups of vanillic acid, chitosan, and poly(vinyl alcohol). The addition of vanillic
acid resulted in homogenous and dense morphology, as confirmed by SEM micrographs. The tensile strength of
active films increased from 32 to 59 MPa as the amount of vanillic acid increased and the obtained values are
more significant than reported polyethylene (2231 MPa) and polypropylene (31–38 MPa) films, widely utilized
in food packaging. Active film's UV, water, and oxygen barrier properties exhibited excellent results with the
incorporation of vanillic acid. Around 40 % of degradation commences within 15 days. Synergistic impact
against S. aureus, E. coli, and C. albicans pathogens caused the expansion of the inhibition zone, evidenced by the
excellent antimicrobial activity. The highest antioxidant capacity, 73.65 % of CPV-4 active film, proved that
active films could prevent the spoilage of food from oxidation. Green chillies packaging was carried out to
examine the potential of prepared active films as packaging material results in successfully sustaining carotenoid
accumulation and prolonging the shelf life compared to conventional polyethylene (PE) packaging.