Effects of Dielectric Barrier Discharge (DBD) Cold Plasma Treatment on Physicochemical and Functional Properties of Peanut Protein

Peanut protein isolate (PPI) solutions were modified by dielectric barrier discharge (DBD) cold plasma (CP) treatment. Effects of CP treatment on the solubility, emulsion stability, and water holding capacity (WHC) of peanut protein were studied. The results showed a significant improvement in solubility, emulsion stability, and WHC following CP treatment. CP treatment resulted in the unfolding of PPI structure, thereby increasing the β-sheet and random coil content and decreasing the α-helix and β-turn content, as analyzed by Fourier-transform infrared spectroscopy. Low-field nuclear magnetic resonance showed an increase in the peak area of T 21 relaxation time by CP treatment and the change in T 21 peak area was in agreement with the result of WHC. This study demonstrated that CP may be successfully applied as a method to modify the functionality of PPI.