What is Wasabi Made Of? Learn to Spot Real vs Fake Wasabi

by Flora Baker

Ah, wasabi – that fiery green paste that many a naive sushi eater has swallowed large amounts of and immediately regretted and is one of the most well-known condiments in Japanese cuisine. We typically know wasabi from those tiny foil packets that come with sushi, nestled alongside a tangle of pickled ginger – but there’s a secret to this spicy stuff. 

It turns out that 90% of the wasabi in the US is imitation wasabi

So where’s all the real wasabi hiding? And where does fresh wasabi even come from? Read on for all the info about real wasabi versus fake and how you can tell the difference. 

What is Wasabi Made Of? 

Wasabi is a type of Japanese horseradish. Though wasabi is known primarily as being in paste form, it’s actually derived from grating the rhizome root of a plant that’s native to Japan. Known by a few names like Wasabia japonica and Eutrema wasabi, this plant is really difficult to grow because it needs specific conditions: a decent amount of shade, constantly moist but not wet soil, high summer humidity but not too much… In fact, authentic wasabi is known as one of the harder plants to grow successfully! 

The wasabi plant is also not one that thrives in the US at all – and importing it from climate-friendly locations, though theoretically possible, is also seriously expensive. Surprisingly enough, wasabi is one of the most lucrative plants on earth, and buying the pure stuff can cost from $160-$250 per kilo when sold wholesale. This is because wasabi root is hard enough to grow properly as is, and growing it on a commercial scale is even trickier. 

wasabi on a plate

Unfortunately, the vast majority of the wasabi that Americans eat is not the real thing (in fact, it’s sometimes referred to as ‘western wasabi’ in Japan!) Instead, it’s a mixture of regular old horseradish that’s powdered and mixed with hot mustard, sweeteners, and green food coloring, all of which is pureed to achieve that familiar paste consistency. 

So how can you spot fake wasabi from true wasabi when you’re out and about? The clues are in its appearance and its flavor.  When the wasabi paste is totally smooth, it’s highly likely to be fake, as the wasabi plant is grated to produce Japanese wasabi, not blended. 

Imitation wasabi also has a very strong flavor which overrules the delicate taste of the fish it’s eaten with. In comparison, true wasabi has a more mellow and pleasant flavor, and isn’t actually spicy – it’s more an aroma of spice than that intense kick we’re used to. 

Why is Wasabi Spicy? 

So what’s the reason for grated wasabi’s intense spiciness? It’s actually how your body reacts to the chemicals present in the wasabi plant. Similar to mustard, fresh wasabi contains a chemical compound called allyl isothiocyanate which stimulates nerve receptors in the mouth and on the tongue. Vapors duly travel through your mouth and into your nasal cavity, prompting that familiar burning feeling in your sinuses. 

If you find grated wasabi particularly overwhelming, there are a few tips and tricks floating around that might help reduce the spice’s impact. Drinking tea beforehand apparently coats the inside of your mouth, which adds a layer of protection. You can also calm the wasabi’s effects by eating it alongside ginger or pepper. 

Luckily there are no known side effects from eating too much real wasabi paste – great news for anyone that loves daring people to eat a full spoonful of the stuff!

How to Try Wasabi at Home

The plus side of this new wasabi discovery? You can actually make wasabi pretty easily for yourself at home if you’ve run out of packets from your local sushi place. Just mix together 2 teaspoons of horseradish, 1 teaspoon of mustard, 1 chopped anchovy, and a few drops of soy sauce. 

Of course, making authentic wasabi the traditional way in Japan is much more of a pure process. Once you’ve washed the rhizome and trimmed off any unsightly parts, you simply grate it like ginger until you have a nice pile of shavings. After you’ve left it for a few minutes for the flavor to accumulate, you can enjoy it with whatever food you’d like. 

Wasabi is a fantastic flavor that’s commonly used in a vast array of snacks.

Whatever you’re in the mood for, Bokksu has got you covered. Why not check out our wasabi products and pick up some spicy treats to snack on?

Author Bio

Flora Baker is a writer, blogger and author based in London, UK. She runs the award-winning travel website Flora The Explorer and has written for Coastal Living, Telegraph, and National Geographic Traveler.