Why do some Balsamic Vinegars cost a few dollars a bottle while other may cost a hundred dollars an ounce.  Is there a difference?

--Bryan

Traditional balsamic vinegar is the result of a long process that starts with the juice, or 'must', of Trebbiano and Lambrusco grapes being boiled until the liquid is reduced to about two thirds of its original volume.  This reduction is done over low heat over several days, resulting in a greater concentration of sugars and starting some of the browning reactions that contribute to the flavor.  This browning reaction is fundamental to a lot of cooking and is described in the posting "Browning Meat for Slow Cooker".

The must is then poured into a wooden cask where it is left to ferment into vinegar.  Rather than the typical, two step approach for traditional vinegar production, where sugars are fermented into alcohol which is then fermented with a second bacteria to make vinegar, traditional balsamic vinegar undergoes both fermentations at the same time.  The sugar to alcohol step involves a particular strain of yeast that will continue to work as the vinegar level rises.

As the vinegar ages, for a minimum of 12 years and frequently much longer, it is moved to progressively smaller casks, each made out of a different wood so that each contributes a particular flavor note to the vinegar.  Traditionally, some older vinegar is blended into the new vinegar to start the fermentation process.

Because of the long process and the reduction in volume that occurs during the making of traditional balsamic vinegar, there is typically a large investment to be recovered from sale of the product.

By contrast, commercial balsamic vinegar is a concoction of boiled must, red wine vinegars, caramel flavoring and other ingredients.  If it is aged at all, the time is shorter, perhaps as little as three years, and the progression through various casks is not done.

In flavor and appearance, traditional balsamic vinegar is usually thicker and more syrupy.  It has a more complex and balanced flavor.  By contrast, commercial balsamic is more watery and has a distinct sweet-and-sour sort of flavor.

Traditional balsamic is used in small quantities to directly enhance the flavor of foods, for example by sprinkling a few drops on strawberries or ice cream or by drizzling it over risottos or grilled meats.  Because of its cost, it is almost never used for things like salad dressings.  Commercial balsamic may be used in dressing or marinades, and is frequently boiled down for sauces or other uses.

If you are looking for authentic, tradictional balsamic vinegar, look for the word "Tradizionale" in Italian on the label.  The two most common types are "Aceto Balsamico Tradizionale di Modena" and "Aceto Balsamico Tradizionale di Reggio in Emilia".  A label which has the word "Vecchio" indicates a 12 year old vinegar while "Extra Vecchio" means it is 25 years old.  Also, look at the ingredients and avoid any offerings that include words like caramel or wine vinegar.

Authentic balsamic vinegar is definitely pricey, but if you can find one within your budget, it is well worth trying at least once.