Review on the loading efficacy of dietary tea polyphenols with milk proteins

In this review, the structural analysis and the loading efficacies of dietary tea polyphenols (+)-catechin (C), (-)-epicatechin (EC), (-)-epicatechingallate (ECG) and (-)-epigallocatechingallate (EGCG) with milk proteins beta-lactoglobulin (beta-LG), alpha-casein (alpha s1-casein) and beta-casein were compared. The multiple spectroscopic results and docking sresults showed that the polyphenol bindings are via hydrophilic, hydrophobic and H-bonding contacts, where larger polyphenols form more stable protein conjugates. The order of protein affinity towards polyphenol was beta-casein>alpha-casein>beta-LG. Loading efficacy was 30-50% for polyphenol-protein adducts. The comparison showed milk proteins are capable of transporting tea polyphenols, which increases the bioavailability of these dietary micronutrients in solution. (C) 2017 Elsevier Ltd. All rights reserved.