The caper (Capparis spinosa L.) is a perennial spiny shrub that bears rounded, fleshy leaves and big white to pinkish-white flowers. A caper is also the pickled bud of this plant. The bush is native to the Mediterranean region, growing wild on walls or in rocky coastal areas throughout. The plant is best known for the edible bud and fruit (caper berry) which are usually consumed pickled. Other species of Capparis are also picked along with C. spinosa for their buds or fruits.
Capparis spinosa is highly variable in nature in its native habitats and is found growing near the closely related species C. sicula, C. orientalis, and C. aegyptia. Scientists can use the known distributions of each species to identify the origin of commercially prepared capers. The shrubby plant is many-branched, with alternate leaves, thick and shiny, round to ovate in shape. The flowers are complete, sweetly fragrant, showy, with four sepals, and four white to pinkish-white petals, many long violet-colored stamens, and a single stigma usually rising well above the stamens.
Capers can be grown easily from fresh seed, gathered from ripe fruit and planted into well drained seed-raising mix. Seedlings will appear in 2-4 weeks. Old, stored seeds enter a state of dormancy and require cold stratification in order to germinate. Cuttings from semi-hardwood shoots taken in Autumn may root, but this is not a reliable means of propagation. Caper plants prefer full sun in warm/temperate climates and should be treated much like cacti. They require regular watering in summer and very little during winter and are deciduous, though in warmer climates they may simply stop growing. Capers have a curious reaction to sudden increases in humidity - they form wart-like pock marks across the leaf surface. This appears to be harmless as the plant quickly adjusts to the new conditions and produce unaffected leaves. Seedling capers can be expected to flower from the second to third year and live for at least decades, and probably much longer.
The buds, when ready to pick, are a dark olive green and about the size of a kernel of corn. They are picked, then pickled in salt, or a salt and vinegar solution, or drained. Intense flavor is developed, as mustard oil (glucocapparin) is released from each caper bud. This enzymatic reaction also leads to the formation of rutin often seen as crystallized white spots on the surfaces of individual caper buds.
Capers are a distinctive ingredient in Sicilian and southern Italian cooking, used in salads, pasta salads, pizzas, meat dishes and pasta sauces. Examples of uses in Italian cuisine are chicken piccata and salsa puttanesca. They are also often served with cold smoked salmon or cured salmon dishes (especially lox and cream cheese). Capers are also sometimes substituted for olives to garnish a martini.
Capers are categorized and sold by their size, defined as follows, with the smallest sizes being the most desirable: Non-pareil (up to 7 mm), surfines (7-8 mm), capucines (8-9 mm), capotes (9-11 mm), fines (11-13 mm), and grusas (14+ mm).
Unripe nasturtium seeds can be substituted for capers; they have a very similar texture and flavour when pickled.
If the caper bud is not picked, it flowers and produces a fruit called a caperberry. The fruit can be pickled and then served as a Greek mezze.
In addition, the Greeks make good use of the caper’s leaves, which are especially desirable and hard to find outside of Greece. They are pickled or boiled and preserved in jars with brine cf. caper buds. Caper leaves are excellent in salads and in fish dishes. Dried caper leaves are also used as a substitute for rennet in the manufacturing of high quality cheese. Capers grown on the island of Santorini are reputed to be of a very high quality, presumably because of the volcanic ash subsoil.
In Greek popular medicine a herbal tea made of caper root and young shoots is considered to be beneficial against rheumatism. Dioscoride (MM 2.204t) also provides instructions on the use of sprouts, roots, leaves and seeds in the treatment of strangury and inflammation. Rutin is a powerful antioxidant bioflavonoid proven to search out super-oxide radicals in the body. Perhaps this explains the Ancient Greeks’ understanding of the caperbush as a vital medicinal plant. Capers contain more quercetin per weight than any other plants.
Etymologically, the caper and its relatives in several European tongues can be traced back to Classical Latin capparis, “caper”, in turn borrowed from the Greek κάππαρις, kápparis, whose origin (as that of the plant) is unknown but is probably Asian. Another theory links kápparis to the name of the island of Cyprus (Κύπρος, Kýpros), where capers grow abundantly.