Fiddleheads are the tightly coiled new growth of ferns. Many fern species produce edible fiddleheads, which are often viewed as a prized delicacy. They are mild in flavor, with a faint hint of forest and almonds, and they are often lightly seasoned so that their flavor is not obscured. They also, of course, form an important part of the growth habit of ferns. When in season, specialty stores may stock fiddleheads, and they can also be collected in the woods.
As a fern grows, it puts out tightly coiled stems of fresh fronds, also called fiddleheads. These stems slowly unfold and expand, with new growth pushing the fiddlehead to straighten and grown longer. Typically, these fronds are found close to the ground, and they may be heavily obscured by old growth. In most cases, the oldest growth on the fern dies back to make way for fresh growth, which will in turn develop spores to disperse the fern.
The fiddleheads of Matteuccia struthiopteris, the ostrich fern, are particularly prized. This fern is also known as a shuttlecock or fiddlehead fern, and it is common in Northern temperate zones across Asia, Europe, and America. Bracken, royal ferns, zemai in Asia, flowering ferns, and cinnamon ferns also yield tasty edible fiddleheads, typically in the spring.
Studies on these growths have suggested that they may contain an as-yet unidentified toxin. Several cases of food-borne illness have been linked to the consumption of undercooked fiddleheads. Therefore, it is extremely important to make sure that fiddleheads are boiled in fresh water for 10 minutes before use, to ensure that the toxin is leached out. It is also a good idea to remove the fuzz and brown chunks with a stiff scrub brush from fresh fronds before cooking. Make sure to select young, tightly cured fiddleheads without signs of mold or decay, as well.
In many parts of Asia, fiddleheads are roasted or grilled. They can also be boiled and then sautéd in butter, or boiled and then reboiled in a fresh change of water. They should ideally be lightly seasoned, and they can also be parboiled and frozen for use later in the year. After blanching and freezing, fiddleheads will keep for several months in the freezer, especially if they are allowed to dry out slightly before being frozen, so that ice crystals do not ruin them.