Fresh wasabi rhizomes are a rare and precious culinary commodity prized by high level sushi and fine dining chefs of Japanese cuisine. Oroshigane means grating metal and also known as oroshiki are graters used in Japanese cuisine. These oroshigane differ from Western-style graters because they have finer grating patterns and use tin-coated copper plates with numerous small spikes on the surface of the metal. This type of graters is the best and are therefore used by leading chefs.
The grater commonly used in Japan
are made from the surface of sharkskin. These graters produce a lot finer
grating at the surface than the metal graters. However, you can use much less
expensive graters made from other materials like plastic or ceramic.
About 15-20 minutes after being grated, wasabi starts to lose
some of its kick; it simply produces a burning sensation in the mouth. To
regenerate the wasabi kick mix a small amount of sugar with the wasabi paste to
enjoy its flavour once more.
After receiving the wasabi rhizomes, place them in a damp
towel/cloth and transfer to a refrigerator. The wasabi rhizomes will remain
fresh for up to four weeks.
The black layer which is only a few millimetres thick on the
outer surface of the wasabi rhizome is due to an oxidation process which occurs
overtime and does not affect the overall quality of the freshly grated
wasabi. If the rhizome is not fresh, you
will notice a white or grey colouration.
This observation is associated with an unpleasant odour. Therefore, if the wasabi rhizome does not
produce an unpleasant odour this indicates that the rhizome is acceptable for
grating. The black layer is just
nature’s way to keep the favour within the rhizome – so it is a good sign! You can consume the black layer, but you do
not have to do this because freshly grated wasabi is much more enjoyable to
eat. Conversely, the black layer protects the rhizome from the effects of
oxygen in the atmosphere. The thin black
layer is easily removed by scraping with a knife or potato peeler, then proceed
to grating.