What's Wasabi?

Although real wasabi is becoming more available, most sushi restaurants outside of Japan still serve up a paste made of horseradish, mustard, and green food coloring and call it wasabi. The truth is that real wasabi is not a type of horseradish. Rather it comes from a plant from a different genus entirely. While wasabi is part of the same family of plants as horseradish, that family (Brassicaceae) also includes mustard, broccoli, and cabbage.

There are, of course, reasons that wasabi is often replaced by a horseradish mixture. First, in its spiciness it shares the same sort of heat possessed by horseradish and hot mustard – the sinus-clearing onslaught that tends to quickly disperse, instead of the lingering burning caused by chili peppers. Second, wasabi is rare and, consequently, expensive. It is primarily grown in Japan, but the demand for it there is so high that Japan ends up as a net importer of wasabi. What difference does real wasabi make? While wasabi shares a similar sort of heat with horseradish, it has a distinctly different taste. The heat it has is slightly mellower than that of horseradish, and it is tempered by a sweet aftertaste. Since I tried real wasabi, the the fake stuff has been mildly disappointing... except on those crunchy peas. It's still addictively good on those. Why is it so rare? Wasabi is picky. It likes to grow in certain conditions... and they aren't convenient conditions. In particular, it really likes to grow on the banks of cool mountain streams. I can't say that I blame it, but I wouldn't mind more inexpensive wasabi sources in my life. (Apparently, the difference between wasabi grown in running water and field-grown wasabi is tasteable.) Fortunately, there are people who are beginning to cultivate it in places other than Japan that have the requisite biomes, such as New Zealand and the North American Pacific Northwest. Greenhouse methods are also being developed with increasing success. I think the place we got our wasabi from was Pacific Farms. They still sell real wasabi paste, but they are no longer shipping the fresh rhizomes. You might have better luck with Pacific Coast Wasabi or Real Wasabi if you want the whole rhizome. (Warning: whole wasabi rhizomes are expensive.) What do you do with it? Wasabi comes in either a prepared paste form or as a whole rhizome that you grate fresh. Fake wasabi also comes as a powder, but I haven't seen real wasabi sold that way. I'd be skeptical if I did, I think it would lose a lot of its flavor if dehydrated. In addition to using it alongside fish, you can use wasabi in most recipes that call for horseradish. I also suspect that it has some untapped culinary potential. When Angela got some rhizomes for Christmas, we used it fairly liberally. It was great with beef, but my favorite thing I did with it was make the most decadent tuna salad ever, which included raw sashimi-grade tuna, homemade mayonnaise, and freshly-grated wasabi. Update Learn more at Real Talk: celebrating the authenticity of Wasabia japonica Also, real wasabi is traditionally grated with dried sharkskin, and that is pretty darn awesome.

Image by Dave B