Pea protein isolate-zein complex particles prepared by hydrophobic interactions and their application in stable Pickering emulsions

Most of the recent studies focus on modifying hydrophobic proteins with hydrophilic components to prepare Pickering emulsion stabilizers. This study reports Pea protein isolate-Zein (PPI-Zein) complex particle prepared by hydrophobic interactions. During the formation of PPI-Zein complexes, the hydrophobic segments of two types of hydrophobic proteins interact to form the core of the particles, while the remaining hydrophilic parts tend to be exposed on the surface of the particles. Therefore, the complex particle has an improved dispersibility, the changed surface wettability and isoelectric point around 4. The diffusion coefficient of these particles is 7.1-11.4 times higher than that of pure zein and 4.0-6.3 times higher than that of pure PPI. As a result, Pickering emulsions stabilized by PPI-Zein complex particles can achieve an oil phase volume fraction of up to 60 (v/v)%, demonstrating good storage stability (up to 30 days), ionic strength resistance (up to 500 mM), high-temperature stability (80 celcius, 48 h) and pH stability (pH 2-9). And the prepared emulsion was proven to have the property of protecting active substances, such as curcumin. These findings indicate potential applications in encapsulation or carrier systems that require clean labels.