Recent advances in starch-based films toward food packaging applications: Physicochemical, mechanical, and functional properties

Interest in starch-based films has increased precipitously in response to a growing demand for more sustainable and environmentally sourced food packaging materials. Starch is an optimal candidate for these applications given its ability to form thermoplastic materials and films with affordable and often sustainably sourced plasticizers like those produced as waste byproducts by biodiesel and agricultural industries. Starch is also globally ubiquitous, affordable, and environmentally benign. Although the process of producing starch films is relatively straightforward, numerous factors, including starch source, extraction method, film formulation, processing methods, and curing procedures, drastically impact the ultimate material properties. The significant strides made from 2015 to early 2020 toward elucidating how these variables can be leveraged to improve mechanical and barrier properties as well as the implementation of various additives or procedural modifications are cataloged in this review. Advances toward the development of functional films containing antioxidant, antibacterial, or spoilage indicating components to prevent or signal the degradation of food products are also discussed.