Kale

Kale
Curly kale, one of the many varieties of kale
Species	Brassica oleracea
Cultivar group	Acephala Group
Origin	Unknown, but before the Middle Ages
Cultivar group members	Many, and some are known by other names.

Kale (English IPA /keɪl/) or leaf cabbage is a group of vegetable cultivars within the plant species Brassica oleracea. They have green or purple leaves, in which the central leaves do not form a head (as opposed to headed cabbages). Kales are considered to be closer to wild cabbage than most domesticated forms of Brassica oleracea.^[1]

Children collecting leaves of red Russian kale (Brassica napus L. subsp. napus var. pabularia (DC.) Alef.) in a family vegetable garden.

Etymology

Kale bears semblance to "kail", a variant of "cawul" derived from Scotland and northern England for various kinds of cabbage.^[2]

Origins

Until the end of the Middle Ages, kale was one of the most common green vegetables in Europe. Curly-leaved varieties of cabbage already existed along with flat-leaved varieties in Greece in the fourth century BC. These forms, which were referred to by the Romans as Sabellian kale, are considered to be the ancestors of modern kales. Russian kale was introduced into Canada (and then into the U.S.) by Russian traders in the 19th century.

During World War II, the cultivation of kale in the U.K. was encouraged by the Dig for Victory campaign. The vegetable was easy to grow and provided important nutrients to supplement those missing from a normal diet because of rationing.^[3]

Description

Some varieties can reach a height of six or seven feet; others are compact and symmetrical and of good quality for eating. Many, however, are coarse and indigestible. Most kale are either annuals or biennials. Seeds resemble those of cabbage in size, form, and color.

A traditional New Years Danish dish: boiled ham, glazed potatoes and stewed kale.

Cultivars

One may differentiate between varieties according to the low, intermediate, or high length of the stem, with varying leaf types. The leaf colours range from light green through green, dark green, and violet-green, to violet-brown.

Classification by leaf type:

• Curly-leaved (Scots kale; blue curled kale)
• Plain-leaved
• Rape kale
• Leaf and spear (a cross between curly-leaved and plain-leaved kale)
• Bumpy-leaved (black cabbage, better known by its Italian translation cavolo nero, and also known as Tuscan Cabbage, Tuscan Kale, lacinato and dinosaur kale)

Because kale can grow well into winter, one variety of Rape Kale is called Hungry Gap, named after the period in winter in traditional agriculture when little else could be harvested.

An extra-tall variety is known as Jersey kale or cow cabbage.^[4]

Kai-lan or Chinese kale is a kale cultivar much used in Chinese cuisine; in English it is occasionally called just "kale".

In Portugal, the bumpy-leaved kale is called by its original Italian name, "cavolo nero", with the expression "couve rebela" also being used.

Ornamental kale

Cultivation

Kale is an annual plant grown from seed over wide germination temperatures.^[5] It is hardy and grows well into winter.^[5]

Decorative uses

Many varieties of kale and cabbage are grown mainly for their ornamental leaves, which are brilliant white, red, pink, lavender, blue or violet in the interior of the rosette. Ornamental kale is as edible as any other variety.^[6]

Nutritional value

In a 100 gram serving, raw kale provides 49 calories and is a rich source (20% or more of the Daily Value, DV) of vitamin A, vitamin C, vitamin K, vitamin B6, folate, and manganese (see table "Kale, raw"). Kale is a good source (10–19% DV) of thiamin, riboflavin, pantothenic acid, vitamin E and several dietary minerals, including iron, calcium, potassium, and phosphorus (see table "Kale, raw").

Boiling raw kale diminishes these nutrient contents, with the exception of vitamin K (see table "Kale, cooked, boiled, drained, without salt").^[7]

Phytochemicals

Kale is a source of the carotenoids, lutein and zeaxanthin (tables).^[8]

As with broccoli and other cruciferous vegetables, kale contains glucosinolate compounds, such as glucoraphanin, contributing to formation of sulforaphane,^[9] a compound under preliminary research for its potential to affect human health.^[10] Boiling decreases the level of sulforaphane, whereas steaming, microwaving or stir frying does not result in significant loss.^[7]

Culinary uses

Kale freezes well and tastes sweeter and more flavourful after being exposed to a frost.^[11] Tender kale greens can provide an intense addition to salads, particularly when combined with other such strongly flavoured ingredients as dry-roasted peanuts, soy sauce-roasted almonds, red capsicum flakes, or a sesame-based dressing.

Regional culinary uses

Europe

In the Netherlands, curly kale is a traditional winter dish called "boerenkoolstamppot", a mix of curly kale and mashed potatoes, sometimes with fried bacon and served with rookworst ("smoked sausage").

In Italy, cavolo nero is an ingredient of the Tuscan soup ribollita. Kale (cavolo nero) is part of many dishes, such as "casseoula" (pork stew) and polenta (corn porridge).

A whole culture around kale has developed in northern Germany, especially around the towns of Bremen, Oldenburg, Osnabrück and Hannover and the region of Dithmarschen. There, most social clubs of any kind will have a Grünkohlessen or Kohlfahrt ("kale tour") sometime between October and February, visiting a country inn to consume kale stew, pinkel sausage, kassler, mettwurst and schnapps. Most communities in the area have a yearly kale festival which includes naming a "kale king" (or queen).

Curly kale is used in Denmark and southwestern Sweden (Scania, Halland and Blekinge) to make (grøn-)langkål (Danish) or långkål (Swedish), an obligatory dish on the julbord in the region, and is commonly served together with the Christmas ham (Sweden). The leaves of the kale are separated from the stem, and then boiled with stock. The result is drained and pressed to remove the remaining liquid. The kale can now be frozen for up to 6–8 months if needed. To make langkål, finely chop the (defrosted) kale and fry it with cream, pepper, and syrup (or sugar) for sweetening. In Sweden, it is also commonly eaten as a soup, with a base of ham broth and the addition of onion and pork sausages.

A traditional Portuguese soup, caldo verde, combines pureed potatoes, diced kale, olive oil, broth, and, generally, sliced cooked spicy sausage.

In Montenegro, collards, kale, locally known as rashtan, is a favorite vegetable. It is particularly popular in the winter, cooked with smoked mutton (kastradina) and potatoes.

In Scotland, kale provided such a base for a traditional diet that the word in dialect Scots is synonymous with food. To be "off one's kail" is to feel too ill to eat.

In Ireland, kale is mixed with mashed potatoes to make the traditional dish colcannon. It is popular on Halloween when it may be served with sausages.

In Turkey, especially in Eastern Black Sea region, kale soup (karalahana çorbası), kale sarma, kale kavurma (sauté), and kale turşu are common dishes.

Asia

A variety of kale, kai-lan, is a popular vegetable in China, Taiwan, and Vietnam, where it is commonly combined with beef dishes. In Japan, kale juice (known as aojiru) is a popular dietary supplement.

Other

In Brazil, it is a side dish for a common stew called feijoada.

Various kale types are also eaten throughout southeastern Africa, where they are typically boiled with coconut milk and ground peanuts and served with rice or boiled cornmeal.

In the Southern United States, kale is often served braised, either alone or mixed with other greens, such as collard, mustard, or turnip. It is also used in salads. Flavored kale chips have also been produced as a potato chip substitute.

Literature

The Kailyard school of Scottish writers, which included J. M. Barrie (creator of Peter Pan), consisted of authors who wrote about traditional rural Scottish life (kailyard = kale field). In Cuthbertson's book Autumn in Kyle and the charm of Cunninghame, he states that Kilmaurs in East Ayrshire was famous for its kale, which was an important foodstuff. A story is told in which a neighbouring village offered to pay a generous price for some kale seeds, an offer too good to turn down. The locals agreed; however a gentle roasting on a shovel over a coal fire ensured that the seeds never germinated.^[12]

Gallery

• 
  Curly-leaf kale
• 
  Red Russian kale
• 
  Making kale chips in Illinois

See also

• Bowen's Kale
• Crambe maritima - Sea Kale

References

External links

Look up kale in Wiktionary, the free dictionary.

Wikimedia Commons has media related to Brassica oleracea var. acephala.

Wikimedia Commons has media related to Brassica oleracea var. sabellica.

• Marrow-Stem Kale – Plants For a Future database
• PROTAbase on Brassica oleracea (leaf cabbage)

Brassica oleracea
Brassica oleracea	Acephala group Broccoflower Broccoli Broccoli sprouts Broccolini Brussels sprout Cabbage Cauliflower Collard greens Gai lan Kale Kohlrabi Red cabbage Romanesco broccoli Savoy cabbage Spring greens
See also	List of cabbage dishes