Brian Mailman wrote:
> Bob (this one) wrote:
>
>> amber wrote:
>>
>>> Have been cleaning out the pantry and have come across various
>>> unopened bottles of red wine vinegar and balsamic vinegar....
>
>> They don't become rancid. They will lose flavor and acidity over time,
>> but it's a long time.
>
> Not true balsamic vinegar... aging is *good* for it. The most valued
> are over 100 years old, I understand. Of course, that's cask-aging, not
> bottle-aging.

It is true. Balsamic vinegar isn't made and then dumped into one barrel
forever. It's topped up as it ages, adding a new infusion of acetic
acid, sugars, etc. each time. Barrel-aging permits evaporation through
the wooden walls thus concentrating the flavoring agents and reducing
the volume. Leaving it in a bottle stops any beneficial aging processes.
Over time, the acetic acid breaks down to other compounds and that
affects other flavoring agents as well. The balance of flavors changes
until it becomes bland.

I tasted some "Aceto Balsamico Tradizionale" in Modena that were
ostensibly more than a century old. They were essentially syrups, having
so concentrated over that time that they poured thickly. They didn't
have a vinegary spirit. They were wonderful for sipping, smooth and very
complex. No one cooks with that stuff. At most, they'll trickle a few
drops over a finished dish. And, in truth, that's all one needs. The
flavors are so dense and rich that drops of it are more than enough. I
bought a bottle (3 ounces) for $90, and the only reason it was that
cheap was because I spoke Italian with the bottler. Took three years to
use it all.

Pastorio