Q&A for How to Make Balsamic Vinegar

Yes, but not cane sugar. The sugar comes from the grapes used in the process; the grape juice is reduced to a syrup, which is semi-caramelized. It does not brown into a full caramel. You may also be tasting the flavors added by the wood casks the vinegar sits in as it ages.

Generally, the more viscous the liquid, the lower its boiling point. As the article states that the "mosto" that is formed by this process ends up being a syrupy liquid, it is very possible that its boiling point is below 195 degrees. Either way, it says the mosto will not generate vinegar if you exceed 195 degrees, so don't.

How many barrels you use will depend on how much balsamic vinegar you're making, not necessarily the amount of years. Fill the largest barrels full of the must first, and then transfer this liquid to roughly 6 other barrels that decrease in size.

The bacteria that produce acetic acid (the main chemical in vinegar) from the alcohol in the wine love oxygen, and will work better in a well-oxygenated environment. The chefs at Noma recommend running an air pump through an air stone to speed up the second stage of the ferment. However, it should be noted that a faster ferment means less flavor development, especially for a long-term ferment like balsamic. If you do speed it up, don’t expect nearly the depth of flavor that comes from a good balsamic. In fact, it’ll probably taste closer to a red wine vinegar, which isn’t bad, but definitely isn’t in the same league as a good balsamic.

You'll need roughly 85-90 pounds of grapes (likely even more) to make roughly 20 liters of must (or grape juice that goes in the barrels).

It's best to buy barrels from a barrel maker, which you can find online by doing a quick search. Most people say that washing out a barrel with clean, hot water is an efficient way of cleaning it, making sure to do several rinses with the hot water.

Typically when fermenting wine, which is what this starts out as, you ferment it until it no longer gives off carbon dioxide which means all the fermentable sugars have been assimilated into alcohol and carbon dioxide. The next step is to take the wine and make it into vinegar, this is where wine stops being wine and becomes vinegar. For further study I would suggest looking into the different types of fermenting i.e. anaerobic, aerobic, etc. You will get a broader sense of how this all works.

It takes around 12 to 50 years. The longer it ages, the more the flavors develop. It is best to aim for about 20 years to get a decent balsamic flavor and tone.