How long can an open sake be used?

Hi,
I have read of many recipes on Japanese cooking mentioning sake as an ingredience. However, I am not sure how long a bottle of sake can be used before it becomes bad taste or even unhealthy to put in food.

As I understand there is not much sake used in each cooking, so buying a bottle for 700-1400 yen for just using once is a bit expensive in the length.

Any clue?

You can use "Box-Wine"(white and cheap wine) as a substitution of "sake" in your country.

If you live in Japan, "Ryori-shu" sake can be purchased at any supermarkets around 150-300 yen per bottle and will last for two month kept in cool place.

The cooking sake - "ryori-shu" as mentioned by tokyo friend 48 will come in handy. The one I have in my kitchen cabinet says it's good until November of this year, if kept unopened, for example. It has been opened, but I will probably use it up in... several months, keeping it in a relatively cool cabinet, and I have not had any problem with using cooking sake this way over the years.

Sake for drinking should be enjoyed in a far shorter time once the bottle is opened. They lose their fragrance as well.

I usually finish the bottle in one sitting! Of course, I buy the little 300ml bottles.

Alright, I will try looking for cooking sake instead. I thought I should buy a drinking sake first though, I doubt I would empty one bottle in a day anyway.

Not sure what to compare sake with, red wine? I can barely drink 1 glass of red wine without getting a bit dizzy :O

"Ryori-shu" cooking sake is not taste as good as liquor sake. You can drink it but is not very tasty. And also, it's not categorized as "liquor", thus liquor tax is excluded, therefore is cheap and can be purchased at supermarkets and combini where they don't have a liquor license.
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