The influence of chemical modification on the physical stability of β-carotene emulsions is shown in SI. 6 (see additional material). Compared with control proteins stabilized emulsions, β-carotene emulsions stabilized by covalently modified LA and LG exhibited better physical stability, while covalent modification of LF or SC did not improve physical stability of β-carotene emulsions. The improved physical stability may be ascribed to smaller droplet size as well as increased electrostatic and steric repulsion between proteins, which were indicated in SI. 5. According to Stokes' law and Deryagin–Landau, Verwey–Overbeek (DLVO) theory, a smaller particle size may result in a slower floating rate and high electrostatic repulsion could prevent emulsion coalescence by strengthening the repulsive force between droplets (Walstra, 1996). As depicted in SI. 6, the physical stability of emulsions stabilized by covalent protein–EGCG complexes followed the order: LG > SC > LA > LF, which suggested that emulsions prepared by covalent LG–EGCG complex and SC–EGCG complex exhibited better physical stability.