Wasabi
Wasabi :originally also known as Japanese horseradish, is a member of the Brassicaceae family, which includes cabbages, horseradish, and mustard. Its root is used as a condiment and has an extremely strong flavor. Its hotness is more akin to that of a hot mustard rather than the capsaicin in a chili pepper, producing vapors that stimulate the nasal passages more than the tongue. The plant grows naturally along stream beds in mountain river valleys in Japan. There are also other species used, such as W. koreana, and W. tetsuigi. The two main cultivars in the marketplace are W. japonica cv. 'Daruma' and cv. 'Mazuma', but there are many others
Uses
Wasabi is generally sold either as a root which is very finely grated before use, or as a ready-to-use paste in tubes similar to travel toothpaste tubes. In restaurants the paste is prepared when the customer orders, and is made using a grater to grate the root; once the paste is prepared, it loses flavor in 15 minutes. In sushi preparation, sushi chefs usually put the wasabi between the fish and the rice because covering wasabi until served preserves its flavor. Fresh wasabi leaves can be eaten, having the spicy flavor of wasabi roots.
Because the burning sensations of wasabi are not oil-based, they are short-lived compared to the effects of chili peppers, and are washed away with more food or liquid. The sensation is felt primarily in the nasal passage and can be quite painful depending on amount taken. Wasabi is served with sushi or sashimi accompanied with soy sauce. The two are sometimes mixed to form a single dipping sauce known as wasabi-joyu. Legumes (peanuts, soybeans, or peas) may be roasted or fried, then coated with wasabi powder mixed with sugar, salt, or oil and eaten as a crunchy snack. Inhaling or sniffing wasabi vapor has an effect like smelling salts, a property exploited by researchers attempting to create a smoke alarm for the deaf. One deaf subject participating in a test of the prototype awoke within 10 seconds of wasabi vapor being sprayed into his sleeping chamber.