A number of variation compounds having CaSR agonist activity were searched, and a novel compound having superior action for imparting rich flavor was discovered. Provided are an agent for imparting rich flavor which comprises the abovementioned substance, and a composite agent for imparting rich flavor which comprises the abovementioned substance and a substance having another CaSR agonist activity. Specifically, provided are an agent for imparting rich flavor which comprises a Lanthionine derivative, and a composite agent for imparting rich flavor which comprises the aforementioned substance and a substance having another CaSR agonist activity.
