Use it until it gets dirty. I've used one-step over and over and over. I have had no ill effects. I only pitch it when it discolors from grain and such. Months.
Oh, and I never refrigerate it.
Every pirate lives for something different. For some, it's the open sea. For others (the masochists), it's the food. For you, it's definitely the fighting. Two things complete your pirate persona: style and swagger. Maybe a little too much swagger sometimes -- but who really cares? Arr!
The lady at the first wine shop I ever went to told me that it's oxygen based, so as long as it makes the "bubbling" sound, it's good. I give it a little shake and listen. If it sounds ok, I use it. Sometimes it's been a couple of weeks or so.
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