Lemons and other citrus fruits aren't the only things that have a tart, acidic flavor -- in fact, there's a green herb that does and it's got a lot of punch for such a small, frilly thing. Its name is sorrel (sor-uhl or saw-ruhl). During the Middle Ages, before citrus fruit ever reached Europe, people used sorrel, a green spinach-like herb, to lend a sour flavor to their cooking. Once citrus fruits gained popularity, sorrel was almost forgotten about, that is until recent years. Sorrel has been making a comeback. But you probably have some questions about it.

Where can I find sorrel?

Sorrel isn't something you'll find readily in supermarkets, but you will find sorrel sold in the farmer's markets. It's categorized as an herb, so you'll most likely find it sold among other herbs, but sometimes it's mixed into salad greens. You can also experiment with growing your own sorrel -- it's very easy to plant from seed. But be wary of insects and critters, such as rabbits, who also love the taste of sorrel.

Why should I be interested in sorrel?

Sorrel is delicious used as an herb or as a salad green -- its tartness is really refreshing. A traditional way to enjoy sorrel is cooked into a sauce and served with fish, lending a lemony flavor without the use of lemon. It's also great cooked into soups or stews. Baby sorrel greens can be tossed into mixed salads. And if you don't have lemons to make a salad dressing, use sorrel to add tang.

What makes sorrel so sour?

The distinctive sour taste of sorrel is due to oxalic acid, which is also present in black tea and spinach. Older sorrel leaves have a higher oxalic acid content, so they will be better for cooking than eating raw. Sorrel also has a very high vitamin C content, which was a reason it was used as a preventative measure for scurvy. Not only is sorrel good to eat, it also has medicinal properties. However, people with arthritis or kidney stones should eat minimal amounts of sorrel because the high oxalic acid content can aggravate those conditions.

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