Utilization of interfacial engineering to improve physicochemical stability of β-carotene emulsions: Multilayer coatings formed using protein and protein-polyphenol conjugates

The impact of lactoferrin (LF)-chlorogenic acid (CA) and (-)-Epigallocatechin-3-gallate (EGCG) conjugates on the physicochemical properties of beta-carotene emulsions was investigated. Formation of lactoferrin-polyphenol conjugates, which was confirmed by SDS-PAGE, caused changes in the structure and nature of lactoferrin. Based on layer-by-layer electrostatic deposition, beta-carotene bilayer emulsions were prepared by lactoferrin and lactoferrin-polyphenol conjugates at pH 7.0. The physicochemical properties of primary and secondary emulsions were evaluated and the results suggested that LF-polyphenol conjugates-stabilized primary and secondary emulsions exhibited better emulsifying properties and improved physical stability of beta-carotene bilayer emulsions under freeze-thaw, ionic strength and thermal treatments. In addition, the lactoferrin-polyphenol conjugates could effectively enhance chemical stability of beta-carotene in oil-in-water emulsions against heat treatment and ultraviolet light exposure, and the least degradation of beta-carotene occurred in LF-EGCG conjugate-stabilized primary emulsion. The interfacial engineering technology utilized in this study may lead to the formation of emulsions with improved physicochemical and functional performance. (C) 2016 Elsevier Ltd. All rights reserved.