Sansai is the Japanese term for a group of vegetables that grow wild throughout the Japanese countryside. The word translates literally as "mountain vegetable." Sansai actually include several vegetables, such as butterbur roots, wasabi leaves and varieties of fiddlehead ferns. Most of these vegetables aren’t readily available in markets outside of Asia, though another sansai vegetable, mitsuba — a three-leaved, long-stemmed herb — is quite common in Japanese markets in some other countries. Takenoko, or young bamboo shoots, also is extremely common in grocery stores outside Japan.
Mountain vegetables usually play a small part in an overall recipe, rather than standing by themselves as a dish. Cooking times generally are short. Common preparation methods are simple, either blanching and soaking or stewing in sauces and broths. Sansai can be fried in tempura batter as well. The flavor tends to be somewhat bitter, and this bitterness can lead to a bit of indigestion if someone eats too much of these vegetables.
The vegetables in sansai are traditionally a sign that winter is ending and spring is on the way, and trips to gather these vegetables in the countryside in Japan aren’t unusual. People who are new to sansai gathering need to learn how to identify the plants, though, to avoid accidentally picking inedible lookalikes. Going out into the field with someone who knows what he or she is doing is a must.
Even edible sansai, however, has its risks. Warabi, also called bracken fern, is a type of fiddlehead fern that contains small amounts of carcinogenic and poisonous compounds such as cyanogenic glycosides and ptaquiloside, which is responsible for poisoning cattle that feed on the plants in larger amounts. Ptaquiloside and bracken fern have been under investigation as a threat to livestock or local water supplies. Not all fiddlehead ferns are warabi, though. Sansai often include two other varieties of fiddlehead fern known as cinnamon fern and ostrich fern, respectively, and a dish containing sansai will often have small amounts of several vegetables, not just ferns.
There also is a more obscure meaning of sansai in Japanese meal planning, in which the san- portion of the word means "three" instead of "mountain." This is a traditional Japanese meal concept involving three dishes plus soup. The context surrounding the word sansai will show which meaning is relevant, however, because menus obviously will not list the three-dish definition as an ingredient.