Preparation, structure evaluation, and improvement in foaming characteristics of fibrotic pea protein isolate by cold plasma synergistic organic acid treatment

Developing hypoallergenic pea protein isolate (PPI)-based foam stabilizers with high foam stability is of great significance to the nutrition and stability of foamed food in the future food industry. Here, a novel non-thermal fibrosis protein modification technology based on cold plasma synergistic tartaric acid (CPA) treatment was used to induce PPI deamidation and thus improve protein solubility, foamability, and foam stability. The results showed that CPA treatment (100 W, 10 min) caused deamidation of approximately 20.02% PPI. The morphology of the CAP-treated PPI aggregate started undergoing fibrosis, with the fiber strip having a length of 7.00–11.00 μm and a width of 0.60–1.00 μm. With CAP treatment, conductivity (111.60 S/m to 129.87 S/m), light transmittance (47.90%–86.90%), foamability (10.00%–112.22%), and foam stability (25.00%–76.82%) significantly increased. Moreover, the thermal denaturation temperature of PPI decreased from 85.29 °C to 82.00 °C. CPA treatment destroyed protein subunits or disulfide bonds and changed the composition and primary structure of PPI. Fourier transform infrared spectroscopy and ultraviolet analysis showed that the α-helix and β-folding contents of the protein's secondary structure were reduced, leading to the unfolding of the rigid structure of PPI, the exposure of hydrophobic groups, and the enhancement of the protein polarityin solution. This research has certain guiding significance and practical value for expanding PPI in the foam food industry and protein membrane field. • Cold plasma synergistic tartaric acid (CPA), a non-thermal deamidation fibrosis technology, was used to prepare fibrotic pea protein isolate (PPI). • CPA technology significantly improved the efficiency of protein deamidation. • CPA technology improved protein solubility, foamability and stability. • This study has significance and practical value for the application expansion of PPI.