Laboratory of Food Chemistry, Wageningen University , Bornse Weilanden 9, 6708, Wageningen, The Netherlands.
J Agric Food Chem. 2013 Oct 23;61(42):10010-7. doi: 10.1021/jf4030823. Epub 2013 Oct 15.
Epigallocatechin gallate (EGCG) has been ascribed to several health benefits, but its bitter taste influences the liking of products with high concentrations of this compound. β-Casein, in particular, and several gelatins are known as strong binders of EGCG, contrary to β-lactoglobulin. The current study aimed at relating the EGCG-binding characteristics of those proteins and their food-grade equivalents to their effects on reducing bitter receptor activation by EGCG in vitro and their bitter-masking potential in vivo. Also in the bitter receptor assay, β-casein showed the strongest effect, with a maximum reduction of hTAS2R39 activation of about 93%. A similar potency was observed for Na-caseinate. β-Lactoglobulin had little effect on bitter receptor activation, as expected based on its low binding affinity for EGCG. The bitter-masking potential of Na-caseinate was confirmed in vivo using a trained sensory panel. β-Lactoglobulin also slightly reduced EGCG bitter perception, which could not be directly related to its binding capacity. The bitter receptor assay appeared to be a valid tool to evaluate in vitro the efficacy of food proteins as complexing agents for masking bitterness.
没食子儿茶素没食子酸酯（EGCG）被认为具有多种健康益处，但它的苦味影响了人们对高浓度该化合物产品的喜爱。β-酪蛋白，特别是几种明胶，与β-乳球蛋白相反，被认为是 EGCG 的强结合剂。本研究旨在将这些蛋白质及其食品级等效物的 EGCG 结合特性与其在体外降低 EGCG 对苦味受体激活的作用以及在体内的苦味掩蔽潜力相关联。在苦味受体测定中，β-酪蛋白表现出最强的效果，对 hTAS2R39 激活的最大抑制约为 93%。类似的效力也观察到了酪蛋白酸钠。β-乳球蛋白对苦味受体激活的影响很小，这与它对 EGCG 的低结合亲和力相符。使用经过训练的感官小组在体内证实了酪蛋白酸钠的苦味掩蔽潜力。β-乳球蛋白也略微降低了 EGCG 的苦味感知，但不能直接与其结合能力相关联。苦味受体测定似乎是一种有效的工具，可用于评估食品蛋白作为苦味掩蔽剂的体外功效。
