Physical and Antioxidant Properties of Cassava Starch–Carboxymethyl Cellulose Incorporated with Quercetin and TBHQ as Active Food Packaging
Antioxidant integration has been advocated for in polymer films, to exert their antioxidative effects in active packaging. In this study, the new antioxidant food packaging made from cassava starch&ndash;carboxymethyl cellulose (CMC), which is biodegradable, edible and inexpensive, was developed. Their properties were determined and applied in food models for application. Antioxidants (quercetin and tertiary butylhydroquinone (TBHQ)) were added at various concentrations into cassava starch&ndash;carboxymethyl cellulose (CMC) (7:3 w/w) films containing glycerol (30 g/100 g starch&ndash;CMC) as a plasticizer. The effects of quercetin and TBHQ concentrations on the mechanical properties, solubility, antioxidative activity, and applications of the films were investigated. Addition of antioxidant improved tensile strength, but reduced elongation at break of the cassava starch&ndash;CMC film. Cassava starch&ndash;CMC films containing quercetin showed higher tensile strength, but lower elongation at break, compared to films with TBHQ. Increases in quercetin and TBHQ content decreased water solubility in the films. Both the total phenolic content and antioxidative activity (DPPH scavenging assay) still remained in films during storage time (30 days). In application, cassava starch&ndash;CMC film containing quercetin and TBHQ can retard the oxidation of lard (35&ndash;70 days) and delay the discoloration of pork.