Genshu

Genshu, written 原酒 in Japanese, is a type of sake that has not been diluted with water after fermentation. The term means “original sake” or “undiluted sake,” reflecting its higher alcohol content and fuller flavor. While most sake are diluted after fermentation to around 15–16% alcohol by volume, genshu typically ranges from about 18–20% ABV, though it can be higher.

Production and characteristics: After the mash is pressed to separate liquid from solids, ordinary sake is diluted with water to reduce strength. In genshu, the dilution step is omitted, preserving the sake’s original strength and intensity. Genshu can be pasteurized or sold as namagenshu (生原酒), meaning it is unpasteurized. Many producers still pasteurize genshu to stabilize flavor and extend shelf life, while namagenshu requires refrigeration and has a shorter shelf life.

Flavor and serving: Genshu tends to be fuller-bodied with more pronounced aroma and a warmer booze presence on the palate. Flavor notes vary by brewer and rice style, but it often carries richer fruit, citrus, or creamy rice characteristics. It is commonly served chilled or at room temperature, though some styles can be gently warmed depending on preference and season.

Storage and handling: Unopened genshu should be stored in a cool, stable environment. Pasteurized genshu has a longer shelf life; namagenshu is more delicate and should be kept refrigerated and consumed sooner after opening.

See also: sake classifications such as junmai, ginjo, and daiginjo, and other post-fermentation practices like dilution and pasteurization.