Innovative composite modification of soybean protein films for nano-TiO₂ migration control and enhanced rapeseed oil storage

Nano-TiO₂ is evenly distributed in protein films modified by CP and TGase. • Protein films with nano-TiO₂ showed improved hydrophobicity and barrier properties. • Nano-TiO₂ enhanced the thermal stability of soybean protein films. • Nano-TiO₂ modified protein films enhanced rapeseed oil storage and shelf life. • Composite modification of protein films reduced nano-TiO₂ migration in packaging. This study investigates the development of functional packaging films by incorporating nano-TiO₂ into SPI and 7S/11S composite proteins. Cold plasma (CP) treatment and CP combined with transglutaminase (TGase) modification were applied to enhance film properties and reduce nanoparticle migration. These protein-based films were tested for packaging rapeseed oil. The results showed that the interaction between TiO₂ and proteins was primarily physical and non-covalent. Incorporating TiO₂ reduced protein film solubility by over 15%, decreased water vapor permeability by up to 22.43%, and improved tensile strength and thermal stability at high temperatures. These effects were more pronounced in films treated with CP and CP-TGase. Furthermore, quality tests on the packaged rapeseed oil demonstrated that films treated with CP and CP-TGase delayed oil deterioration. The combination of CP and TGase also helped limit the migration of nano-TiO₂, which is crucial for mitigating the potential hazards of metal nanoparticles in functional food packaging. Download: Download high-res image (205KB) Download: Download full-size image