The stem or the rhizome is the most valuable part of the wasabi plant. These dutch grown wasabi rhizomes toke 18-24 months to grow full-size. They are harvested to order to ensure their freshness. Sizes vary between 80 and 150+ grams.
Source
Not all Japanese sourced wasabi are equal. Our Japanese wasabi is only sourced from farms in Shizuoka prefecture, in particular the Amagi area which is renowned for high quality wasabi.
Wasabi in this area is cultivated on steep terraces filled with wasabi. Crystal clear spring water flows down from the mountains where it fills the pumice stone wasabi terraces; this water delivers nutrients, minerals and dissolved oxygen that are vital for wasabi plants to thrive. Trees and the steep valley sides provide natural shade from the summer sun.
Many different varieties of wasabi are grown in the area, some are particular to individual growers. The Isewan typhoon of 1959 flooded Amagi with such devastating effect that all wasabi varieties were washed away. Mazuma wasabi from Wakayama was re-planted and much of the wasabi grown in the area now is derived from this variety.
Our guides to the best wasabi, and wasabi famers, are Yoshiharu-san and his father Takahashi-san. Takahashi-san has over 50 years’ experience sourcing wasabi from all over Japan for the top restaurants in Tokyo.
Most growers of the best wasabi in Japan are small family businesses, this combined with wasabi’s long production cycle of at least 18 months means Yoshiharu-san will source our wasabi from various growers throughout the year. This ensures a continuous supply of the highest quality wasabi.
Processing
The wasabi paste is created by grating the wasabi rhizome. This paste gives a sharp kick with a sweet aftertaste. This taste arises because the cells are grated and react with the air.
A standard kitchen grater is not suitable for grating wasabi. Use a good wasabi grater to get a nice wasabi paste with the right taste.
After grating, the wasabi can be used fresh for about 15 minutes. Of course you can also use the wasabi in a recipe. The pungency remains best recognizable in greasy recipes. However, wasabi gives it its own "wasabi" flavor in addition to a sharp taste.
Storing
If the wasabi rhizome is delivered vacuum sealed, open the package upon arrival by e.g. cutting in the top part of the packaging. The key is to prevent the rhizome to dry out too much while providing enough fresh our preventing the head to deteriorate too fast.
As a result, the wasabi can be kept in the refrigerator for up to 2 weeks. Sometimes the outside gets a little brown or the head a bit dry or soft. Cut the head off or scrape a thin layer of the rhizome. The inside will be untouched.
