Namazake (生酒) is sake that has not been pasteurized even once after pressing. Only sake that meets this condition may be labeled “生酒”.
What pasteurization is
Pasteurization (hiire, 火入れ) is a process of warming sake to kill the bacteria that spoil it. It stops enzyme activity and keeps the quality stable. Most sake is pasteurized twice: before storage and when it is bottled.
Namazake, nama-chozo-shu and namazume-shu
| Name | Pasteurized before storage | Pasteurized when bottled |
|---|---|---|
| Namazake (生酒) | No | No |
| Nama-chozo-shu (生貯蔵酒) | No | Yes |
| Namazume-shu (生詰酒) | Yes | No |
| Ordinary sake | Yes | Yes |
“生貯蔵酒” (nama-chozo-shu) may also be used on the label only for sake that was stored without pasteurization after pressing and pasteurized when it was shipped.
Notes on storage
In namazake, the enzymes are still active. For this reason, its quality changes sooner and more than that of pasteurized sake. The labels of sake that has not been pasteurized give notes on storage and on how to drink it. If the label says “要冷蔵” (keep refrigerated), please store it in a refrigerator.