Soy Protein Isolate (SPI)-Based Films/Coatings for Food Packaging: Research Progress on Properties and Applications

Films and coatings made from soy protein isolate (SPI) have become a cutting-edge approach to environmentally friendly food packaging, providing benefits like non-toxicity, biodegradability, and renewable supply. This review studies a comprehensive overview of SPI, including its classification, properties, and applications in food packaging. SPI-based film preparation techniques have been studied, including the development of composite soy protein films, including other proteins, polysaccharides, and biopolymers. The effects of different material blends on the mechanical, barrier, and thermal properties of SPI films are discussed, highlighting the role of SPI-based films and coatings for upcoming food packaging applications and the different structured composites in improving functionality. SPI has excellent film-forming properties, and the properties of SPI-based food packaging films can be adjusted through various strategies. SPI-based food packaging films/coatings have been used in various food preservation applications.