Unfavorable smell which is generated when sake becomes oxidized due to reasons such as "Maturing progressed too much (over maturing)," "degraded before maturity" and "improper storing method."
「熟成が進みすぎた（過熟）」、「熟成しないうちに劣化した」、「保存方法が正しくなかった」などの理由で、酒が酸化してしまったときに生じる異香。