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The truth about wasabi: you’ve probably never tasted the real thing, but we have

We’ve been lied to this whole time #shook.

by: Katy Rose | 10 Apr 2019
wasabi, sushi, fake, expensive

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In 2019, sushi is central to big city dining. We eat sushi at markets and in malls, we order it to our desk and it’s not unusual to find a sushi menu at your neighbourhood restaurant or even in a steakhouse. 

There is a ritual to eating sushi that is both challenging and comforting at the same time. We have learnt to have all the equipment and essential condiments on hand - chopsticks, small dipping bowl, soya sauce, soft pink flakes and that little blob of green paste. 

Who would ever consider a sushi meal without soya sauce, wasabi and pickled pink ginger? I can’t imagine it! And so I was stunned and shocked to learn this week that the green stuff we’ve been eating all along is not really wasabi at all. 

The real thing
Real wasabi is not only almost impossible to farm, especially on the scale that would satisfy the world’s sushi-lovers, but the flavour itself is so delicate and fleeting that it must be eaten within minutes of preparation. 


Honwasabi (true wasabi from the Wasabia japonica plant) is grown naturally in fresh mountain streams of Japan, or sometimes coaxed into growing in flooded gravel fields. The plant is very fussy, and will only grow in a very specific temperature range. The wasabi plant requires just the right combination of water and humidity. It can take years before the plant is ready to harvest, making wasabi farming slow and very expensive. 

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The root part is harvested, similar to its European cousin horseradish, and sold to the very best sushi restaurants in Tokyo and the world. 

Once the root is in the hands of the chef, the wasabi requires further careful treatment to reveal its spicy, pungent flavour. The root is traditionally grated on a decorative stiff board covered in rough shark skin. Nowadays, chefs are more likely to use a delicate handmade ceramic grater, that has little sharp raised bumps that grind the wasabi pulp into a paste. 

The action of grating breaks open the plant cells allows their compounds to mix together. As you crush the root, enzymes are released and it is this chemical reaction that we taste when we taste wasabi. 

Almost like the spark from a firecracker, once the chemical reaction is completed the flavour is gone. Just like that. 

wasabi, sushi, fake

So just what does fresh wasabi taste like? We visited South Africa’s most prestigious traditional Japanese restaurant, Kyoto Sushi Garden in Cape Town to talk to owner Scott Wood about his special delivery of fresh wasabi from Japan.

Scott brings out the wasabi - it is about the shape and size of a medium carrot, with dark brown skin on the outside and vibrant green showing through where the wasabi has been grated previously. He rubs it vigorously on the wasabi board in small energetic circles, and slowly a smooth paste begins to gather. 

The flavour of the wasabi paste will deteriorate after a few minutes, and so it must be prepared fresh for every dish. 

The smell is the first thing I noticed. It smells fresh and green, like very faint cut grass. He offers us some to taste - he encourages us to take more than usual as fresh wasabi’s flavour is milder than the cheaper alternatives. It zings a little on the tip of my tongue, and then fills my mouth with a fresh elegant flavour. It reminds me of the feeling of champagne bubbles. The taste is herbaceous with a hint of sweetness, like the cousin of a very strong rocket plant. 

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sushi, wasabi

We taste the fresh wasabi with a piece of raw salmon, and suddenly it all makes sense. The wasabi elevates the flavours and heightens the textures. Imitation wasabi so often overpowers and dominates the sushi, but here the real product compliments and uplifts the sashimi. 

So what is the wasabi we’ve been eating the whole time? Scot explains that it is a combination of mustard seeds, white horseradish and green food colouring. It’s a cheaper substitute for the real thing and it can be dangerously potent. 

Scot orders his wasabi roots from Japan, and he says he pays about R4000 a kilo after all the transportation costs. Yes, it’s expensive he admits, but he doesn’t charge extra for the fresh wasabi. “I like to offer something special in my restaurant. It’s a wonderful feeling tasting wasabi for the first time.” 

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