Can you settle a pressing disagreement?
Does vinegar ever go bad? When , if ever, does the Veil /Mother become inactive?
As in ChefOno's example the finest balsamico from Modena could be 85 or more years old. As it ages it gets moved to smaller and barrels. That stuff you apply with an eye dropper. You wouldn't use it in a salad. Maybe a couple of drops on a piece of parmigano.
wine can also get better with age... but an opened bottle of wine doesn't. Anything can be aged and improved under the correctly controlled environment, but I still believe that an opened bottle of vinegar will eventually be unusable. Although I do agree the shelf life is much much longer than most products due to the acidity as ChefOno said.
I think vinegar will, infact go bad with enough time. I've actually seen it grow mold. That being said, i have vinegar in my kitchen that has been there for at least a year, and I still use it. The rule I have made up for myself is.... If it's still clear, then its good to use. If it starts to get cloudy, I start to get nervous and just dump it.
I've been doing research on this "mother" you all speak about. I've never read up on this stuff. does it change the flavor or your vinegar at all? perhaps I was wrong. Maybe vinegar never goes bad... lol
I have never noticed a change in flavor but, then again, I don't do shots of vinegar. I think it's safe to say any change in flavor is negligible.
I think the answer is to realize that vinegar is "bad" by it's very nature. Better to ask if your vinegar has turned really evil. If it's cloudy you can filter it. It's only bad. If it smells like anything but vinegar, it is evil and must go.
My bottle of rice wine vinegar dates from the Mao administration.
"Administration" is a charitable way to describe The Great Helmsman.
pierino, my charity runneth over. It seems to be trying to ketchup to my sense of humor.