Effect of interaction between pea protein isolate and whey protein isolate on encapsulation of resveratrol

Resveratrol (Res) has many potential benefits for human health. This investigation employed a complex protein system comprising pea protein isolate (PPI) and whey protein isolate (WPI) as an innovative carrier for Res delivery. The effect of PPI and WPI binding on protein conformation was investigated and differences in Res delivery by PW (pea protein isolate-whey protein isolate) complex protein and single PPI and WPI proteins were compared. The secondary structure and surface hydrophobicity results showed that the formation of PW complex protein increased the flexibility and surface hydrophobicity. Fluorescence spectroscopy results indicated that compared to single proteins, PW complex protein could bind more efficiently to Res through hydrophobic interactions. The PW-Res complex achieved higher encapsulation efficiency (EE), improving by 59.17% and 25.80% over PPI and WPI, respectively, and more significantly increased the antioxidant activity of Res by 36.89%. Furthermore, the smaller average particle size (173.95 ± 10.94 nm) and larger absolute value of ζ-potential (27.07 ± 0.49 mV) of the PW-Res complex resulted in better stability compared to the PPI-Res and WPI-Res complexes. This study has significant implication for encapsulation of hydrophobic active ingredients such as Res using complex protein systems.