Though they are often mistakenly used interchangeably, balsamic vinaigrette and balsamic vinegar are not one and the same. Period. A vinaigrette is a cooking sauce or salad dressing made by mixing vinegar, oil and seasoning so balsamic vinaigrette should therefore presumably be made from balsamic vinegar but since the vinaigrette is so mass produced, one can never really be sure.
Traditional balsamic vinegar, on the other hand, is one of Italy's most precious gastronomic treasures, made from a reduction of Trebbiano and Lambrusco grape juice, which is boiled down to 30% of its original volume to create a must and then aged for a minimum of 12 years–otherwise 18 or 25–in barrels made from different types of wood.
Source: http://www.swide.com/
