ref=”https://thinktasty1.wpengine.com/wp-content/uploads/2014/08/rsz_mtxtfyg.jpg”>A while ago, I mentioned the time I tried to make gari — pickled ginger for sushi — and couldn’t get it to turn pink. I thought maybe I’d used the wrong kind of vinegar. (I’ve found out that very young ginger is supposed to turn pink when pickled, but most commercially pickled ginger has been helped out with beet juice or artificial dye.)

Vinegar is one of those supplies you can have around for most of your life without ever thinking much about what it is, where it comes from, or why it does what it does. Doing some pickling this summer has finally turned my attention to it.

So, what exactly is vinegar? It’s mostly water and acetic acid — but that doesn’t mean diluted acetic acid is vinegar. In fact, the FDA has ruled that it isn’t. There are further acids, salts, and other substances in vinegar, and though there’s very little of them, they’re what make the difference.

Vinegar starts out as — well, almost anything with fermentable carbs: wine, cider, even honey. A fermentation process turns the sugar into alcohol, then the alcohol into acetic acid. Once, this took a long time, but now vinegar can be made by a fast process.

So it’s pretty much an acid you can safely use in food, in small amounts. As an acid, it has a sharp taste, good for balancing sweet or bland tastes in food. It also has the power to break down meat tissue, making it more tender, which is why you’ll find it in many marinades. Something else vinegar can do is destroy bacteria, so it’s used in pickling to keep the food from spoiling for months to come. (Even cooks like me, who don’t feel comfortable pickling for the long term, use it in refrigerator pickles for that classic sharp taste.)

Different kinds of vinegar include wine and cider, as mentioned above, and balsamic, which has nothing to do with balsam but is made from grape juice. (People once thought it had the same healing qualities as balsam, and they may not have been far off.) The vinegar used to pickle ginger is made from either rice or a by-product of sake.

Does it matter what kind of vinegar you use? Though it’s best to use what your recipe says to get the exact taste intended, what’s important is the acidic sharpness. In other words, if plain white vinegar is all you’ve got, use it rather than skip making the dish.