What are the principal characteristics of a DOC Aceto Balsamico? A very official document issued by the Maestri Assaggiatori di Modena (Master Tasters of Modena) states that:

• The traditional balsamic vinegar is obtained from the boiled must of grapes, which is subjected to a long process of natural fermentation and concentration.
  
• This is to be effected over an exceptionally long ageing period in a succession of barrels made of various types of wood, strictly without the addition of aromatic substances.
  
• Of a lively, brown color, it should manifest a molasseslike consistency, a mildly acidic nose a which is at once penetrating and agreeable.
  
• The traditional taste is a smooth, subtle interplay of sweet and sour flavors. It is a full, rich taste in complete harmony with the olfactory properties.