A few weeks ago, I bought my first bottle of Umeboshi Plum Vinegar. I bought it a my local HFS. It is a smallish, brown glass bottle with a shaker top. I tried the UPV and immediately fell in love with it. I started putting it on everything.
I have kept it in my pantry as I do all vinegars. I didn't use it for about a week, and when I went to use it yesterday on some Talapia, I got a distinctively funky taste from it. Sort of reminded me of dirty socks.
Can UPV go bad? Should it be stored in the fridge? I took a look at the bottle and didn't notice anything about specific storage.
I think I'm going to throw this bottle out and start fresh, but I've only had it a couple of weeks, and have used only the tiniest bit. I would hate to think that it is that perishable. And, no, my house isn't warm (in fact, often too chilly for some family members), nor was it exposed to any significant heat.