Physicochemical characterisation of β-carotene emulsion stabilised by covalent complexes of α-lactalbumin with (-)-epigallocatechin gallate or chlorogenic acid.

•(−)-Epigallocatechin gallate (EGCG) and chlorogenic acid (CA) were covalently linked to α-lactalbumin (α-La).•The impact of protein–polyphenol complexes on the stability of β-carotene emulsions was monitored by the types of the polyphenols.•α-La–EGCG covalent complex stabilised β-carotene emulsions improved physical stability and inhibited β-carotene degradation.•α-La–EGCG covalent complex could be applied as an emulsifier with antioxidative activity in emulsion systems.