To search a number of variation compounds having a CaSR agonist activity in order to obtain a substance having a more excellent kokumi-imparting function, and more particularly to provide a kokumi-imparting agent, which contains the foregoing substance, and a composite kokumi-imparting agent, which likewise contains the aforementioned substance and another substance having a CaSR agonist activity as well, in combination a kokumi-imparting agent comprises a lanthionine derivative and a composite kokumi-imparting agent comprising the lanthionine derivative and another substance having a CaSR agonist activity.本發明係提供一探索具有CaSR促效劑活性的多數變異化合物而發現更為優異之具賦予濃厚味作用的新穎化合物,並提供由該物質所構成之濃厚味賦予劑、及由該物質與其他具有CaSR促效劑活性之物質所構成之複合濃厚味賦予劑。本發明係由羊毛硫胺酸衍生物所構成之濃厚味賦予劑,及在該物質中倂用其他具有CaSR促效劑活性之物質之複合濃厚味賦予劑。