Biodegradable Cassava Starch-Based Films Formulated with Coconut Oil for Sustainable Food Packaging

A large volume of plastic waste is disposed of in the environment and in landfills worldwide. To remediate this serious environmental issue, sustainable alternatives to substitute traditional fossil fuel-derived plastics are necessary. In this regard, starch-degradable films are a promising avenue for promoting sustainability in the food industry due to starch's low cost, non-toxicity, availability and desirable film-forming capacities. However, starch-based films may have challenging water vapor barrier properties and mechanical resistance. To address this issue, in this study, we investigated the use of coconut oil (CO) to improve the performance of biodegradable cassava starch-based films. Different formulations (glycerol content and CO emulsion) were tested and the developed films were assessed regarding their morphology, mechanical properties, water permeability and biodegradability. The best formulation (COF-1) was achieved using 8.70 g of glycerol and 0.5 g of CO emulsion and showed better homogeneity and uniformity and improved mechanical properties. COF-1 showed a maximum tensile strength of 8.12 ± 1.99 MPa, almost three times higher than the control cassava starch-based film (CSF) produced without CO. The water vapor permeability (WVP) of COF-1 was 4.14 ± 0.56 g·mm·m-2·day-1·kPa-1, almost one-third lower compared to commercial cellophane. The incorporation of CO emulsion in the polymer matrix had a positive impact on the mechanical properties and showed good results of barrier and morphological properties. Overall, our work shows that enhanced starch-degradable films formulated with CO are potential solutions to conventional plastics, contributing to a cleaner environment and a more sustainable future.