Preparation and characterization of poly (vinyl alcohol) (PVA)/basmati rice starch (BRS) blend films cross-linked with aliphatic and aromatic carboxylic acids for food preservation and packaging

In the current study, three different carboxylic acids were incorporated as a cross-linker into the blend films of polyvinyl alcohol (PVA) and basmati rice starch (BRS) at a 70/30 ratio and plasticized with glycerol. The cross-linking succeeds through the creation of ester bonds between the free hydroxyl groups of PVA/BRS and the C = O groups. The effect of this cross-linking on physicochemical properties (film thickness, retraction ratio, moisture content, water absorption, and water vapor permeability) and optical (transmittance and color analysis), antimicrobial, and antioxidant properties was assessed. The current findings showed that COA incorporation into the PVA/BRS blend films demonstrated better hydrophobicity and excellent UV light-blocking properties. The incorporation of COA has no impact on radical scavenging activity; however, the cinnamic acid- and benzoic acid-containing films at higher percentages possess antimicrobial properties. FTIR studies confirm the existence of hydrogen bonding interactions among the PVA/BRS blend film and COA. The study encompasses the swelling properties of the blend film in water, brine, and seawater. The cast blend films can be utilized for the packaging purposes of foodstuffs.