Think You've Been Eating Wasabi All This Time? Think Again.

Wasabi: you know it well, or so you think. Chances are, however, you've never actually eaten real wasabi, or at least not very often. This is because most of the wasabi served outside of Japan is a mixture of horseradish, mustard and food coloring. Even in Japan, the demand for real wasabi is so high that you'll often find the horseradish mixture instead, with little, if any, real wasabi mixed in.

Real wasabi tastes more herbal than the horseradish stuff. It's hot but doesn't have a lingering, burning aftertaste. It's supposed to taste smoother, cleaner and more "plant-like" than its commonly used substitute. The horseradish paste served in restaurants is harsher and not as fresh-tasting.

So now that you know you're probably eating fake wasabi, what does real wasabi look like and where does it come from?

Real wasabi comes from grating the root Wasabia Japonica.

Ryouchin via Getty Images

Most of the wasabi you'll find in Japanese restaurants in the United States and even often in Japan is not real wasabi.

Most wasabi sold in the United States is really just horseradish.

Debbi Smirnoff via Getty Images

Horseradish grows faster and bigger than Wasabi Japonica, and it is cheaper to produce. Even in Japan horseradish is often used in place of Wasabi japonica.

Wasabi Japonica originated in Japan.

Stefano Scata via Getty Images

Mentions of the plant have been found in botanical books and dictionaries in Japan that trace back to 794 CE. Today, however, it is also grown in China, Taiwan, New Zealand, Australia and North America.

The leaves of the wasabi plant are also edible.

Steamy Kitchen

They can be eaten raw in salads, pickled or even fried into chips.

Real wasabi loses its flavor after 15 minutes or so.

d3_plus D.Naruse @ Japan via Getty Images

For the freshest wasabi, you must grate the root right before serving, as the wasabi will only hold its strong flavor for about 15 minutes after preparation.

Wasabi has long been said to have medical properties.