Composite films comprising modified corn starch and gelatin were developed using a solvent casting technique. The effect of varied content of citric acid and gelatin on the functional properties of the corn starch and composite films, respectively, was investigated. Modified corn starch films enriched with 5% citric acid presented excellent film properties like solubility, swelling index, water vapor permeability, and mechanical property as compared to other films. Similarly, composite films enriched with a ratio (4:1) also exhibited excellent film properties like mechanical and opacity than other composite films. FTIR results confirmed the cross linking among the modified corn starch chains, which is responsible for the enhancement in the film properties. From SEM results, it was noticed that the modified corn starch films exhibited slightly rougher, less shiny than the composite films. Efficacy of the composite solution as a coating formulation in terms of the quality and shelf life of the cucumber investigated. From the results, it was noted that the composite film forming solution as a coating formulation has the potential to extend the shelf-life of the cucumbers additionally up to 16 days.
Keywords: Citric acid; Composite film/coating; Cross-linking; Cucumber; Gelatin; Shelf life.
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