I saw the new bottle of vinegar from the grocery store today and it said “Artificial Vinegar”. This may be due to Islamic interpretations of what is allowed and not allowed.

Also it is noteworthy that the Qur’an specifies intoxicants, as being Haram. An intoxicant is, by definition, a substance eaten, drunk or smoked with the sole intention of becoming intoxicated, or a substance created with that purpose in mind. This basically means alcoholic drinks and narcotic drugs.

Any food which was made with an alcoholic drink is Haram because, although the food itself probably couldn’t get you drunk, its alcoholic ingredient was made for that purpose. So make sure you check the ingredients label carefully!

In contrast, alcohol can be found in some Halal foods, such as bread, soy sauce and vinegar (even cider vinegar or wine vinegar). These sometimes contain minute amounts of alcohol as a result of a natural reaction between certain chemicals during the manufacturing process (as opposed to alcoholic drinks being deliberately added to food to add flavour), and so couldn’t be classified as Haram. From: Islam Online

Also Islam Online also says:

… What I see is that if wine changes into vinegar, it becomes pure and lawful as it has changed from its original state and this requires a new ruling as is the case with all other converted impurities regardless of whether this occurs naturally or by human interference. Wine itself is a pure substance as it was made from grapes. After becoming an intoxicant, it becomes prohibited. Once it changes and lacks the intoxicating characteristic, it regains its original ruling. …

“Artificial vinegar” is acetic acid that is made by a chemical process. “Natural vinegar ” is acetic acid that is made in a biological process using the Acetobacter aceti bacteria. If the “natural vinegar” is distilled, it is very difficult to tell the difference between it and the “artificial vinegar”.

From: The difference between artificial vinegar and natural vinegar