Synthesis of N'-[(2,4-dimethoxyphenyl)methyl]-N-(2-pyridin-2-ylethyl) oxamide and evaluation of its taste-enhancing effect

The development of efficient and safe taste-enhancing compound is important to reduce sodium intake, at the same time maintains food palatability. Hence, in this study, an excellent and safe taste-enhancing compound (N'[(2,4-dimethoxyphenyl)methyl]-N-(2-pyridin-2-ylethyl) oxamide (DE)) was synthesized in 96% yield under optimized conditions. The chemical structure of DE was clearly characterized by 1H and 13C NMR spectrum. Human sensory evaluation showed that the addition of DE (0.9 ppm) significantly enhanced the kokumi, umami, and salt tastes, the degree of enhancement by 66.4%, 56.6%, and 26.2%, respectively. The result of electronic tongue was consistent with the human sensory evaluation, which was again illustrated that DE is a promising taste-enhancer. Time-intensity (TI) results revealed that the sample (with addition of 0.9 ppm DE) umami duration (210.0 & PLUSMN; 0 s) were significantly prolonged that of control group (150.0 & PLUSMN; 0 s). Moreover, the DE could bind and activate calcium-sensing and T1R1/T1R3 receptors, inducing stronger umami and kokumi tastes. This work revealed the potential of DE as an excellent taste enhancer.