There is also the possibility that your red wine vinegar could develop what is known as a mother. This is a combination of bacteria and yeast that forms into a gelatinous sheet or disc.

Unlike traditional red wine which is made through the ... introduce acetic acid bacteria into diluted wine by way of a mother ...

Cheap vinegar, produced from inferior red wine, will give poor results to your finished dish. Buy good quality, aromatic vinegar with a complex flavour. The label will often specify which type of ...