Disclosed is a flavor-enriching agent comprising a substance discovered by searching for a number of variation compounds having a CaSR-agonizing activity. Said substance exhibits an improved flavor-enriching action, particularly with respect to initial tastes, exhibits an improved stability, and can be produced by a simple method at a low cost. Also disclosed is a composite flavor-enriching agent comprising said substance and another substance having a CaSR-agonizing activity. Specifically disclosed are a flavor-enriching agent comprising γ-Glu-Nva (L-γ-glutamyl-L-norvaline), and a composite flavor-enriching agent comprising the aforesaid substance together with another substance having a CaSR-agonizing activity.
