Effect of chlorogenic acid covalent conjugation on the allergenicity, digestibility and functional properties of whey protein

We investigated the allergenicity, digestibility and functional properties of whey protein isolate (WPI) after covalent conjugation with chlorogenic acid (CHA). The covalent conjugation of CHA may cause an unfolded protein structure. The WPI–CHA conjugate showed lower IgE binding capacity but higher intestinal digestibility than unmodified WPI. Furthermore, after digestion, the IgE binding capacity of β-lactoglobulin and α-lactoalbumin was lower in the digested WPI–CHA conjugate than digested WPI. Moreover, the solubility, emulsifying activity, foaming properties and antioxidant capacity of WPI were enhanced by covalent conjugation of CHA. Covalent conjugation with CHA might reduce the allergenicity in vitro of WPI by improving the functional properties of the protein.