Eutrema wasabi (formerly Wasabia japonica), a perennial herb which is not related to horseradish but resembles it in flavour, and is often referred to as ‘Japanese horseradish’. It is found elsewhere in E. Siberia, but belongs essentially to Japan, where it is used extensively, providing one of the most important flavourings in Japanese cookery.
The plants grow wild in or on the banks of mountain streams and are cultivated in flooded mountain terraces. This cultivation requires great care, since the water temperature has to remain a constant 11–14 °C (51–7 °F) throughout the year. Nagano, Shizuoka, and Shimane are the main growing districts in Japan. The plants take several years to reach maturity.
The Japanese name is said to mean ‘mountain hollyhock’. The roots are sold in Japanese grocery stores in pans of water. Peeled and trimmed, they are grated into a fine paste, pale green in colour. This is used especially with sushi and sashimi (raw fish) and in soups, to which it adds considerable pungency.
A wasabi pickle is also made; the leaves, flowers, stalks, and rhizomes are chopped, brined, and then preserved in saké lees and (subsequently, before use) mixed with mirin and sugar.
Fresh wasabi can rarely be obtained outside Japan. Tins of wasabi powder (to be prepared like mustard powder) or tubes of wasabi paste may be used instead.
Alan Davidson was a distinguished author and publisher, and one of the world's best-known writers on fish and fish cookery. In 1975 he retired early from the diplomatic service—after serving in, among other places, Washington, Egypt, Tunisia, and Laos, where he was British Ambassador—to pursue a fruitful second career as a food historian and food writer extraordinaire. Among his popular books are Seafood of South-East Asia, North Atlantic Seafood, and Mediterranean Seafood. In 2003, shortly before his death, he was awarded the Erasmus Prize for his contribution to European culture.
