That light green paste sitting next to your California roll, or offered as an addition to your poke bowl, is known as wasabi. However, there’s at least a 90% chance that it’s not really wasabi. In fact, most people live their whole lives without consuming real wasabi.
What is wasabi?
Wasabi is most commonly known as the spicy green paste served as a condiment to all forms of sushi. But you can use wasabi to spice up any recipe, like these Wasabi Beef Fajitas. True wasabi is made from the rhizome (like a plant stem that grows underground where you would expect to see a root) of the Wasabia japonica plant.
Its signature clean spiciness comes from allyl isothiocyanate instead of pepper’s capsaicin. (Where do your favorite peppers rank on the Scoville heat scale?) This is why people sometimes describe a feeling of wasabi heat going “up their nose” when they take a bite. The scent receptors for wasabi are packed tight in our nasal passages!
What does wasabi taste like?
Real fresh-grated wasabi tastes bright and green with a touch of quickly fading heat. It is pungent, yet delicate enough to let the flavor of raw fish shine. The hit of heat provided by the wasabi served with sushi is meant to highlight fish’s flavor, not cover it.
In the best sushi restaurants, the chef will portion wasabi onto each piece of sushi (usually nigiri style) to balance with the strength of flavor from the fish.
Fake “wasabi” burns much hotter and longer because it is made from horseradish and sometimes mustard. Too much of this imitation wasabi will totally obscure the delicate taste of the sushi.
What is most “wasabi” made of?
A true wasabi plant is part of the Brassicaceae family. Horseradish, radishes and mustard are also in this family and have a similar hot flavor to wasabi. Since authentic wasabi is expensive, most wasabi found in grocery stores and with prepackaged sushi is made of powdered horseradish and artificial color. It may also contain mustard powder and thickening agents like flour or cornstarch. If you love that horseradish zip, try these horseradish recipes.
How can you tell real and fake wasabi apart?
To spot fake wasabi, first look at the texture. A pasty and thick consistency is a sign of imitation wasabi (the horseradish is usually pureed completely smooth). Real wasabi will have a grated, gritty texture.
In order to capture the most flavor possible, real wasabi is always served freshly grated. The traditional method for grating is to run the root in circles over sharkskin which acts like sandpaper, shearing very fine pieces of wasabi from the root.
What makes real wasabi so expensive?
The Wasabia japonica plant is incredibly hard to grow because it needs to be partially submerged in moving water, which is not a common farming structure. In Japan, wild wasabi grows in rocky riverbeds. It is also a sensitive plant that can be killed by small changes in environment or humidity, according to this BBC interview.
Most wasabi is cultivated in Japan, although a handful of farms have popped up in North America. Why farm such a finicky plant? Because the rhizomes can be sold for more than $75 a pound. This extreme cost is also why you won’t see the real thing in most restaurants and definitely not at the grocery store.