I've never eaten a packet of salt and vinegar crisps and thought to myself if only this were chardonnay vinegar. This is aside from the fact that ready salted is the only true way (and none of that reduced salt nonsense, they're crisps, not health food).
I don't know what dried acetic acid is (pure anhydrous acetic acid is a liquid above about 17 degrees) - I presume in this case, they removed the acetic acid and water and left the 'chardonnay flavours,' leastways those that aren't volatile and they put the acid tingle back with citric acid.
While you might have had an allergic response to something in them, it's probably just the citric acid – it's what it says it is, and it's also going to dry out your lips and mouth. You can verify by buying a tub of food-grade citric acid and sticking your tongue in it. Or find an experimental (children might be useful, but remember to use all of them).
Also, sugar in crisps, good god. It makes me want to hunt down everyone involved the creation of that diabolical concoction with angry pigs.