Binkakoi Hiire (bottle pasteurization)

Binkakoi Hiire is a method of heat treatment (pasteurization) carried out on sake while it is in the bottle during production. In this process, the bottled sake is warmed in hot water, which helps suppress microbial activity and prevent oxidation. This helps maintain the quality of the sake and makes long-term storage possible. The method is also known as bin-kan hiire (瓶燗火入れ) and is used to stabilize sake without compromising its flavor or aroma. Sake treated with Binkakoi Hiire tends to stay fresh after opening and is easier to keep in good drinking condition.