PROBLEM TO BE SOLVED: To provide a method to utilize pericarp of Citrus jabara which is previously disposed of and to solve problems especially concerning drinks about removal of bitter taste from pericarp of Citrus jabara and how to effectively extract narirutin which is considered to be effective to pollinosis and the like.SOLUTION: This invention obtains functional extract for foods and drink which satisfactorily addresses the problems through the following four processes: the first process in which pericarp of citrus jabara is boiled and heated in fluid containing milk the second process in which the pericarp after the first process is washed the third process in which the pericarp after the second process is immersed in water for six or more hours and the fourth process in which the fluid obtained in the third process is sterilized.
