Will the Real Wasabi Please Stand Up?

We have some surprising sushi news: wasabi, also known as “Japanese horseradish,” may not be as exotic as you think. According to TIME, much of the green stuff we get in the US is actually an amalgamation of impostor ingredients: traditional horseradish, mustard, and either green food coloring or spirulina.

Better than the real thing?
Even in Japan, many sushi bars serve this “Western wasabi” because wasabi root is expensive and in high demand (up to $125/pound in the US). First introduced to Japan in the 1860s, horseradish was a welcome economic solution for Japanese businesses: it grows faster and larger than wasabi, and is more profitable to produce.

The nose knows
Both horseradish and wasabi create a heat felt more in the sinuses than on the tongue, but real wasabi has a complex depth of flavor, and a spiciness that dissipates quickly into a palate-stimulating, fruity sweetness that compliments the flavor of fish. What’s more, according to recent studies, real wasabi could be a cancer-fighter: Georgetown University’s research found that a chemical contained in wasabi called “isothiocyanate” may bind to a defective protein in cancer cells, leading to cancer cell death. Some research has also noted wasabi’s anti-inflammatory capacity and potential to prevent food poisoning—another argument for serving it with raw fish.

Get real
One way to ensure you’re getting the authentic article is to purchase the root and grate it yourself (some West Coast farms have found ways to grow the notoriously difficult plant outside of Japan). When freshly grated, wasabi packs a super-strong flavor, though it loses much of that punch when exposed to air even for a short while, and the root spoils in just a week. If you can’t find it in stores, look for online vendors like North Carolina-based Real Wasabi that sell the rhizomes (stems), powdered or tubed wasabi bearing the name “Wasabia Japonica.” Even genuine powdered or tubed wasabi, however, often contains horseradish to approximate the spicy, sinus-clearing kick of fresh wasabi.

If you’re at a restaurant, ask your waitstaff if they offer fresh wasabi or “hon-wasabi,” which is how chefs in Japan distinguish the true variety from the imitation product. If they have the real thing, it will likely come out grated, rather than as a putty-like paste.

Seems it’s not easy being green.