PROBLEM TO BE SOLVED: To provide a bitterness masking agent which masks, for gastric absorption, safely, inexpensively and easily, bitterness of an edible material including a drug food-and-drink, even when the edible food-and-drink is a fine powder or a whole fruit, by using a traditional food material, in a long-term antifungal/denaturalization-preventive way, even in an ordinary-temperature hydrated state of the edible food-and-drink, without degradation or denaturalization of the contained ingredients or production of industrial waste.SOLUTION: A bitterness masking agent for masking of the bitter ingredient of olive contains ethanol-containing sake lees or calcium hydroxide as an effective ingredient having action of masking the bitter ingredient of olive and is used effectively by simple mixing. A bitterness masking method uses the bitterness masking agent in masking the bitter ingredient of olive. The bitterness masking method may includes additionally a step of a treatment with carbonates. The bitterness masking method may comprise masking the bitterness ingredient of olive contained in an edible material and improving the shelf stability of the edible material. An edible material containing the bitter ingredient of the olive and the bitterness masking agent is also provided.
