Off-flavor
オフフレーバおふふれーばOff-flavor refers to undesirable odors or tastes in sake. These flavors can arise during production or storage, and may be caused, for example, by fermentation problems, contamination by unwanted microbes, or deteriorated raw materials. Because off-flavors detract from the character of sake, great care is required in brewing. They can also affect health, so it is best to avoid sake that has an abnormal aroma or taste.