The eminent Muslim scholar and renowned Da`iyah, Sheikh `Abdel Khaliq Hasan Ash-Shareef, states: “This is a controversial issue among Muslim scholars. According to the Shafi`i madhhab, it is haram to use such vinegar. According to Shafi`i scholars it is haram because the wine turns into vinegar by adding a material on it and this new addition becomes contaminated by wine and therefore it becomes haram even if it turns into vinegar.
However, other Imams of Fiqh are of the opinion that it is permissible. This is because as long as the essence of the substance of khamr (wine) changed to another material (i.e. vinegar), then there is nothing wrong in making use of it.”