Koshu (aged sake)

Koshu (aged sake) refers to sake that is shipped and served after a period of storage, in contrast to shinshu, the new sake brewed within the current brewing year. In general, sake aged for three years or more from the time of production is considered koshu. Aging softens the flavor and gives the sake a distinctive depth. Because there is no clear regulation governing how koshu is labeled, long-aged sake of 3 or 5 years, and even 10 or 15 years, is well known. Sake that has undergone long aging takes on an amber color and complex aromas, and falls among the more expensive types of sake. In the sake industry, once the brewing year changes, all sake brewed before that point is also called koshu, so the definition of koshu can vary depending on actual brewing practice and the season. Koshu is a special category in which aging draws out the sake's inherent appeal, allowing drinkers to experience its true value.