Polysaccharide-based films of cactus mucilage and agar with antioxidant properties for active food packaging

Abstract

The production of films derived from renewable resources for food packaging applications is an important research area within the scope of sustainable development. Herein, fully biobased films made from cactus mucilage (CM), extracted from Algerian Opuntia ficus-indica cladodes, and agar (A), extracted from marine red algae, were assembled via solvent film casting method. The effect of agar concentration on the properties of the plasticized CM films (40 wt.% glycerol) was evaluated at three different mass ratios of CM/A, namely 70:30, 60:40 and 50:50. Overall, the results revealed that the polysaccharide-based films exhibited good mechanical properties (Young’s modulus ≥ 135 MPa and tensile strength ≥ 5.3 MPa) and UVlight protection (transmittance ≤ 40% (200–400 nm)), as well as thermal stability up to 140 °C, low water vapor transmission rate (WVTR ≤ 10.6 g h−1 m−2) and moderate antioxidant activity (DPPH scavenging ≥ 19% and ferric reducing antioxidant power ≥ 1.3 mg AAE per g of film). Following from this, the pliable freestanding CM/A-based films with UV protection, water barrier properties and antioxidant activity can be a low-cost and eco-friendly option for the development of active food packaging materials.