Development of ionic liquid plasticized high‐tensile starch‐protein‐sorghum bran composite films with antimicrobial activity

Abstract

AbstractIonic liquid (1‐butyl‐3‐methyl imidazolium chloride—[bmim]Cl) was used as a plasticizer alternative to enhance the mechanical strength of the starch‐zein composite films. Additionally, sorghum bran extract (SBE) was utilized as a sustainable source of bioactive compounds to introduce the antimicrobial activity to the composite films. [Bmim]Cl provided better solubilization capacity thereby enhancing the compatibility of film components. Thus, [bmim]Cl substantially improved the tensile strength and elongation at break of the ionic liquid plasticized (8.93 ± 1.59 MPa and 29.53 ± 0.86%) as well as sorghum bran functionalized films (8.99 ± 0.42 MPa and 21.91 ± 0.76%). Incorporation of SBE to the potato starch‐zein film solution enhanced opacity and attributed antioxidant properties to the composite film and that endorsed the possibility of inhibiting lipid peroxidation. Furthermore, the sorghum bran functionalized films possessed antimicrobial activity against Escherichia coli, making them appropriate for active packaging applications.