Speaker 1: Welcome to brain Stuff, a production of I Heart Radio,
Speaker 1: Hey brain Stuff, Lauren Boga bam here. If the wassabi
Speaker 1: that the waiter brings out to a company your sushi
Speaker 1: could talk, it would have some explaining to do. It's
Speaker 1: highly unlikely that that pungent green paste is the real thing.
Speaker 1: It's probably not even close. The wissabi served in American
Speaker 1: restaurants is actually a mixture of mustard, horseradish, and green
Speaker 1: food coloring. That's because real sabi is very expensive, sometimes
Speaker 1: more than a hundred dollars a pound outside of Japan.
Speaker 1: Though even in Japan it's rare for restaurants to use
Speaker 1: it because it's not cheap and it must be freshly graded.
Speaker 1: The part of the wisabi plant that's used as a
Speaker 1: condiment is the rhizome. It's a root like stem that
Speaker 1: grows underground, like ginger or potatoes. The whole plant is
Speaker 1: actually edible, but the rhizome is especially prized for its
Speaker 1: sharp flavors. If you're lucky enough to go to a
Speaker 1: restaurant serving the real thing, they may even bring the
Speaker 1: rhizome to the table along with greater so that they
Speaker 1: can grade it as freshly as possible for you. That's
Speaker 1: because wassabi starts to lose its kick around fifteen minutes
Speaker 1: after being graded or cut. Because that amazing kick comes
Speaker 1: from one of the plant's defense mechanisms, and it's not
Speaker 1: a permanent feature of the rhizome. You see, Wasabi doesn't
Speaker 1: have much scent until it's cut or grated. But when
Speaker 1: its cell walls are broken, say by the teeth of
Speaker 1: a hungry herbivore or a chef's knife, compounds from inside
Speaker 1: and outside those cells mix and undergo a chemical chain
Speaker 1: reaction that creates pot tasting compounds during one phase of
Speaker 1: the chain. This is an evolutionary trait meant to deter
Speaker 1: animals from eating the plant, But suckers, we humans have
Speaker 1: decided that we dig that flavor. While imitation with sabi
Speaker 1: is very hot with a mustard pepper sort of flavor,
Speaker 1: the real stuff doesn't have the same harshness or burn
Speaker 1: and tastes more vegetile, earthy, and smooth with just a
Speaker 1: hint of sweetness. Was Sabi is so expensive because it's
Speaker 1: hard to cul to eight. It's known as the hardest
Speaker 1: plant to grow commercially in the world. The best was
Speaker 1: zabi called Sabo sabi is grown in flooded beds of
Speaker 1: gravel or preferably in cool mountain streams. The roots sink
Speaker 1: down into the soil below, the rhizomes grow in the gravel,
Speaker 1: and the leaf stems poke up above the water. Lower
Speaker 1: quality plants are grown in fields in soil called oka
Speaker 1: wasabi for processing into dried powder for snack crackers and
Speaker 1: the like. But either way, was sabi's leaves and stems
Speaker 1: are brittle. It wants temperatures to stay between fifty and
Speaker 1: seventy degrees fahrenheit that's about eight to twenty celsius, and
Speaker 1: like me, it won't tolerate direct sunlight. It doesn't do
Speaker 1: well in greenhouses, so it can really only be grown
Speaker 1: in appropriate natural environments. So when restaurants are trying to
Speaker 1: keep costs down, they substitute the aforementioned horse radish mixture
Speaker 1: for real was sabi. The reason this works is because
Speaker 1: both ingredients get their pungency from the same family of
Speaker 1: herbivore deterrent compounds called isothiot Science nates and scientists are
Speaker 1: looking into a sabi's medicinal properties. It appears to relieve
Speaker 1: allergy symptoms, fight cancer, and inhibit bacterial growth, though more
Speaker 1: research is needed. The antimicrobial attribute might be why it
Speaker 1: traditionally accompanies sushi. It's a way of counteracting any possible
Speaker 1: ill effects of eating raw fish. Today's episode was written
Speaker 1: by Katherine Whitburn and produced by Tyler Clang. The brain
Speaker 1: Stuff is production of I Heart Radios How Stuff Works.
Speaker 1: To learn more about the history, science, and culture of sabi,
Speaker 1: check out my other podcast, Saber. We did an episode
Speaker 1: on it in December, and of course, for more on
Speaker 1: this and lots of other hot topics, visit our home
Speaker 1: planet has Stuff works dot com plus for more podcasts
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