The huge part of what one actually can buy under the name of “wasabi” is actually not containing any piece of that fragile plant: you might never have taste original Japanese wasabi (山葵).
In Europe and the United States, the green paste accommodating sushis and sashimis is usually containing less than 30% of original wasabi (and more often less than 5%). That fake wasabi is containing a mixture made of horseradish, water and colorants. In contrast, the “true wasabi” is a delicate plant, long and difficult to grow, and whose subtle flavor is vanishing about 15 minutes after it had been grated. In Japan, it is the pride of mountainous Utogi in Shizuoka prefecture.
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Youko Siratori knows pretty well wasabi (山葵). On that cold December morning, while the sun finally succeeded to find its way through the valley, the 65-year-old is strongly raking 150 sq ft of gravel. Up in the Shizuoka mountains, Utogi-born Youko is running her farm by herself. And the raking is nothing more than the first of many steps to grow sawa wasabi, the more renowned one (not to be mistaken with the soil-grown one, the oka wasabi).
“Then the gravel must be washed, is smiling Youko pointing the hose she just unwound across the neighboring path. Wasabi is fragile and will grow smoothly only if everything is perfect.” Around Youko, the wasabi terraces, on gravel areas because the plant is growing in white water, are following each other up and down the tiny mountain stream.
A native plant from Japan
Wasabi (山葵), before its rhizome is grated to obtain the subtle flavored green paste, is no more than a tiny plant. Before the Muramachi era (1336-1573), when Japanese understood how to grow it, it was naturally flourishing in some streams of Japan and Sakhalin. Mainly in the mountains, where the water temperature is about the same all year round, between 13 and 18°C.
Then wasabi became truly fashionable during Edo era, from 1600. Japanese farmers became masters in growing the stream plant, mainly in what is now Shizuoka prefecture, while the city people began to use it with raw fish and soba noodles. The true wasabi is not essentially spicy-hot – it is more like a really strong flavor going up in the nose, like mustard.
From several centuries now, the village of Utogi, where Youko is running the family farm, is the place of a top range wasabi.
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“The wasabi growing will last one year and three months before it reaches the harvesting size, is detailing Youko while looking up the numerous terraces along the stream. These ones will be ready next month.” On the next terrace, a few wasabi are blooming in winter thanks to the December sun.
The fragile plant’s sunlight exposition is a big deal for the farmers. It has to be the right daily amount, meaning that they are constantly looking up the sky, ready to protect the plant with long fabrics at any time. Upstream, some terraces are already covered by translucent plastic tarp to prevent the leaves from freezing. (And at the top on the Aozasayama mountain, one can discover an original view over Fuji-san).
At least 2000 yens for 100g
Downstream, Youko is now harvesting some matured plants, successfully grown after 15 months. Under the wide green leaves, the stems are gathering in a thick rhizome (of 8 to 15 cm long), from where the tiny roots are coming and which will be grated to obtain the flavored paste.
“But we first need to remove carefully all the roots and wash the plant”, describes Youko while she is filling a blue plastic crate with her wasabi. Fifty meters away, on the other side of the stream, three Japanese monkeys are running away along tea fields, the other pride of Utogi.
Youko’s wasabi’s rhizomes will cost about 10000 yens each (about 85US$). The wasabi prices are usually beginning around 15US$ for 100g, depending on the quality and origin.
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The national production of wasabi, being so long and complicated to grow, is not enough for Japan. Moreover, a part is also exported to high range restaurants all over the world. That explains why the “fake wasabi” had been created, first for domestic market and then for Japanese affordable restaurants.
Original and fake wasabi
The wasabi paste available in sushi restaurants worldwide is usually composed of horseradish. A big part is produced in China and shipped to Japan, where original wasabi might be added to the mixture. In Europe, the wasabi tubes containing at least 5% of original one are allowed to display the picture of the plant.
The substitute is about ten times less expensive than original wasabi. Aside horseradish, it contains mustard seed, soy floor, colza oil and maize starch, salt and sugar, dome thickener and some sweetener. The mixture, not yet green like proper wasabi, then needs food coloring to get the right color (mainly, and depending of the country, tartrazine and brilliant blue FCF) whose effects on health are unclear.
To appreciate the original wasabi subtle flavor, its rhizome must be kept in the fridge (one month maximum) and grated five minutes before the meal. The plain aroma is thus revealed. The step is really important : the chefs are using special wood and shagreen (ray or shark skin) graters.
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Back to Utogi, Youko is having lunch down the village, after a hard morning that began long before December sun rose. In the canteen-like restaurant, posters are already announcing the coming mochitsuki. “You can eat everything in wasabi, she says. Not only the rhizome, but also the leaves and the stems”. For lunch, aside soba noodle, she is having some wasabi leaves tempura.
The stems are used to make a special sake, called logically wasabizake. In Utogi, the small plant is everywhere. From the walls of the village to the manhole covers (highly decorated as anywhere in Japan), one cannot miss it.
How to get there?
The easiest way to visit Utogi (有東木) is by car. The village is only 20 miles from Shizuoka, where one can rent a car. Still the journey through mountainous small road takes about one hour (but is worth the drive). Several buses also leave Shizuoka station and do reach Utogi but the trip is a bit longer (about 1h15, 1200 yens and 57 stops)
Discover more:
Last fall, a youtube video revealed the secrets of original wasabi, by introducing the Daio Farm of Hokata. On wasabi.org, a long article describes the benefits of its consumption for health.
Some wasabi is also growing in Europe, mainly in ancient watercress farms. That is the case of The Wasabi Company in England, on their Dorset and Hampshire farms.