PROBLEM TO BE SOLVED: To provide an excellent glycation inhibitor and a food and a drink containing the inhibitor, and a method of masking bitterness and astringency by chlorogenic acid.SOLUTION: There are provided the glycation inhibitor containing a chlorogenic acid as an active ingredient and the food and the drink containing the inhibitor. The method of masking bitterness and astringency by a chlorogenic acid which includes combining the chlorogenic acid with a processed product of du zhong leaves is also provided.