The corn-kernel-size caper adds a salty, pungent flavor to salmon dishes, Italian sauces and other foods. But what are these dark-green garnishes?
Capers are the unopened flower buds of a Mediterranean plant: Capparis spinosa, or caper bush, a shrub that thrives in semiarid and arid regions, even growing amid rocks.
After harvesting, the caper buds are pickled or brined, causing them to release mustard oil (glucocapparin), which intensifies their flavor.
Capers appear frequently in Mediterranean dishes, particularly Italian staples like chicken piccata and spaghetti alla puttanesca. They are often used to garnish smoked and cured salmon, especially lox and cream cheese. You'll find capers in tartar sauce and Niçoise salads, too.
The fruits of the caper bush, similarly dried and pickled, are also edible, and are sold as caper berries. They often join olives, cheeses and other small savories on Middle Eastern-style mezze (small) plates. Caper leaves can also be eaten in salads.
Caper buds must be picked by hand; machines would damage the delicate floral shoots. This need for manual labor explains capers' high cost, with jars usually running $6 to $17. You can make a "poor man's caper" by cooking nasturtium seeds with vinegar, pickling salt, garlic and other seasonings.