I haven’t felt this betrayed since I found out I’ve never eaten yams. Turns out, unless you happen to live in Asia, you’ve probably never had real wasabi either. That sinus-clearing green concoction on your plate of sushi is an impostor, or seiyō wasabi (“western wasabi”). It’s a mix of regular ol’ American horseradish, mustard, and green colouring.
True wasabi, which is grown in rocky riverbeds, is actually rather rare (and expensive) outside of Japan. It has traditionally been paired with sushi not only for it’s unique flavour, but also health reasons. Wasabi is a natural anti-microbial agent, so it was beneficial to match with raw fish before the modern standards of food preparation came into existence. (it may also explain why it’s so hard to find wasabi yogurt)
The easy way to tell between real and fake wasabi is by it’s appearance. The “western wasabi” looks like a lump of putty or paste. The real stuff looks like what it is… a finely grated root. Next time you’re in a nice Japanese restaurant, ask if they have fresh wasabi. According to the “sushi fanatic” author of my source, it’s worth the effort and expense.
Bonus Fact: Those same anti-microbial elements have been put to the test in labs to determine that wasabi actually makes an effective bacteria-battling toothpaste. That’ll wake you up!