Posted by: Didapper PJ11 SEP 2013
If you enjoy sushi, you will be familiar with the glob of green wasabi paste glooped onto the side of your plate. And, if you are partial to oriental nibbles, you may well have snacked on peas or peanuts coated with wasabi.
But probably not. Your alleged wasabi will almost certainly have been a poor imitation made from horseradish beefed up with mustard and salt and dyed a garish green with food colourings.
Outside Japan, genuine wasabi tends to be used only by high-end restaurants whose affluent clients can afford the authentic product.
Authentic wasabi commands a high price because it is hard to cultivate. It occurs naturally in mountain river valleys in Japan, but few other places offer ideal conditions for its growth.
Wasabi japonica is a member of the large Brassicaceae family, best known for green vegetables such as cabbage and root vegetables such as turnip. The family also includes various sharp-tasting plants such as mustard, radish and horseradish. But wasabi is unusual in that it produces vapours that stimulate the nasal passages rather than the tongue. This pungency is attributed to isothiocyanates released when the rhizome is grated.
Because wasabi’s effect is not unlike that of smelling salts, it has been studied as a possible smoke alarm for the deaf. In one test, a subject awoke within 10 seconds of wasabi vapour being sprayed into his sleeping chamber.
In 2011, researchers who investigated the ideal density of airborne wasabi for waking people in an emergency were awarded the Ig Nobel prize, an accolade that celebrates quirky and imaginative research.
Studies have also shown that wasabi may inhibit the growth of micro-organisms. A project by Japanese and South Korean researchers found that all parts of the plant have a bactericidal action against several strains of Helicobacter pylori. As bacteria increasingly show resistance to mainstream antibiotics, perhaps wasabi offers one way forward.