Wasabi paste Wasabi paste is spicy and pungent in flavour and is most commonly served with sushi and sashimi. The vapours tend to stimulate the nose more than the taste buds, and its unique taste and smell are due to the formation of volatile compounds known as isothiocyanates when the cells are ruptured from being cut or grated. Fresh wasabi paste loses its pungency when exposed to air, so the rhizome is often grated immediately before serving, traditionally with a sharkskin or wooden grater. It is also available as a dried powder or in a tube. True wasabi is naturally green in colour, while Western wasabi, made of horseradish, usually has green colorants added. Shelf Life :18 months