Carrot is a herbaceous root vegetable, Daucus carota subsp. sativus, in the parsley family (Apiaceae or Umbelliferae), which also includes the similar parsnip. The domesticated carrot is a cultivar of the wild carrot (Daucus carota), also known as “Queen Anne’s lace,” which is native to temperate parts of Europe and southwest Asia. The term carrot also applies to the long, edible, usually tapering taproot of the domesticated form. These taproots commonly are orange in color, but may be a variety of colors depending on the cultivar, including white, pink, yellow, or purple. They have a crisp texture when fresh.
Carrots growing wild play a valuable role in the ecosystem: the leaves and roots are a source of food for animals, such as larvae of Lepidoptera species, and carrot flowers provide nectar for bees, who in turn pollinate the plants. The domesticated carrot provides a nutritious food for humans, and its distinctive flavor, texture, and color is a source of joy. Humans have learned how to cultivate this root vegetable, produce diverse cultivars of it, and prepare it in many ways, including eating it raw, cooking it in a soup or stew, making carrot cake, and so forth.
Daucus carota is a member of the Apiaceae or Umbelliferae family (both names are allowed by the International Code of Botanical Nomenclature). This family comprises unusually aromatic plants with hollow stems, including the cumin, parsley, carrot, parsnip, dill, caraway, fennel, and other relatives. The family also includes some highly toxic plants, such as hemlock.
Apiaceae is a large family with about 300 genera and more than 3,000 species. The earlier name Umbelliferae derives from the inflorescence (arrangement of flowers on a stem) being in the form of a compound “umbel.” Each umbel comprises many small radially symmetrical flowers with five small sepals, five petals, and five stamens.
The wild carrot, Daucus carota, known also as bishop’s lace or Queen Anne’s lace, is a flowering plant in the family Apiaceae that is native to temperate regions of Europe and southwest Asia. Daucus carota subsp. sativus is the domesticated form of the wild carrot Daucus carota. It has been bred for its greatly enlarged and more palatable, less woody-textured edible taproot, but is still the same species.
Wild carrot is a variable biennial plant, usually growing up to one meter (39 inches) tall and flowering from June to August. The umbels are claret-colored or pale pink before they open, then bright white and rounded when their hundreds of tiny blossoms are in full flower. The umbels measure 3-7 centimeters (1.2 – 2.75 inches) wide with a whorl of narrow bracts beneath. Finally, as the flowers turn to seed, the umbels contract and become concave like a bird’s nest. This has given the plant its British common or vernacular name, bird’s nest. Very similar in appearance to the deadly poison hemlock, it is distinguished by a mix of bi-pinnate and tri-pinnate leaves, fine hairs on its stems and leaves, a root that smells like the cultivated carrots, and occasionally a single dark red flower in its center.
Wild carrot was introduced and naturalized in North America, where it is often known as “Queen Anne’s lace.” It is so called because the flower resembles lace; the red flower in the center represents a blood droplet where Queen Anne pricked herself with a needle when she was making the lace. The function of the tiny red flower, colored by anthocyanin, is to attract insects. Because Queen Anne’s lace was introduced into North America as a foreign species, the United States Department of Agriculture has listed it as a noxious weed.
The edible part of a domesticated carrot, Daucus carota subsp. sativus is a taproot. It grows a rosette of leaves in the spring and summer, while building up the stout taproot, which stores large amounts of sugars for the plant to flower in the second year. The flowering stem grows to about one meter (39 inches) tall.
The wild ancestors of the carrot are likely to have come from Afghanistan, which remains the center of diversity of D. carota, the wild carrot. Selective breeding over the centuries of a naturally-occurring subspecies of the wild carrot, Daucus carota subsp. sativus has produced the familiar garden vegetable (Rose and O’Reilly 2006; Mabey 1997).
In early use, carrots were grown for their aromatic leaves and seeds, not their roots. Some relatives of the carrot are still grown for these, such as parsley, fennel, dill, and cumin. The first mention of the root in classical sources is in the first century C.E. The modern carrot appears to have been introduced to Europe in the eighth to tenth centuries; Ibn al-Awam, in Andalusia, describes both red and yellow carrots. Simeon Seth also mentions both colors in the eleventh century. Orange-colored carrots appeared in the Netherlands in the seventeenth century (Dalby 1997).
In addition to wild carrot, these alternative (mostly historical) names are recorded for Daucus carota: bee’s-nest, bee’s-nest plant, bird’s-nest, bird’s-nest plant, bird’s-nest root, carota, carotte (French), carrot, common carrot, crow’s-nest, daucon, dawke, devil’s-plague, fiddle, gallicam, garden carrot, gelbe rübe (German), gingidium, hill-trot, laceflower, mirrot, möhre (German), parsnip (misapplied), Queen Anne’s lace, rantipole, staphylinos, and zanahoria (Spanish) (Nowick 2007).
Carrot cultivars can be grouped into two broad classes, eastern carrots and western carrots. More recently, a number of novelty cultivars have been bred for particular characteristics.
Eastern carrots were domesticated in Central Asia, probably in modern-day Afghanistan in the tenth century, or possibly earlier. Specimens of the eastern carrot that survive to the present day are commonly purple or yellow, and often have branched roots. The purple color common in these carrots comes from anthocyanin pigments.
The western carrot emerged in the Netherlands in the fifteenth or sixteenth century, its orange color making it popular in those countries as an emblem of the House of Orange and the struggle for Dutch independence. The orange color results from abundant carotenes in these cultivars. While orange carrots are the norm in the West, other colors do exist, including white, yellow, red, and purple. These other colors of carrot are raised primarily as novelty crops.
The Vegetable Improvement Center at Texas A&M University has developed a purple-skinned, orange-fleshed carrot, the BetaSweet (also known as the maroon carrot), with substances to prevent cancer, which has entered commercial distribution.
Western carrot cultivars are commonly classified by their root shape:
- Chantenay carrots are shorter than other cultivars, but have greater girth, sometimes growing up to eight centimeters (three inches) in diameter. They have broad shoulders and taper towards a blunt, rounded tip. They are most commonly diced for use in canned or prepared foods.
- Imperator carrots are the carrots most commonly sold whole in U.S. supermarkets; their roots are longer than other cultivars of carrot, and taper to a point at the tip.
- Danvers carrots have a conical shape, having well-defined shoulders and tapering to a point at the tip. They are somewhat shorter than imperator cultivars, but more tolerant of heavy soil. Danvers cultivars are often pureed as baby food.
- Nantes carrots are nearly cylindrical in shape, and are blunt and rounded at both the top and tip. Nantes cultivars are often sweeter than other carrots.
While any carrot can be harvested before reaching its full size as a more tender “baby” carrot, some fast-maturing cultivars have been bred to produce smaller roots. The most extreme examples produce round roots about 2.5 cm (one inch) in diameter. These small cultivars are also more tolerant of heavy or stony soil than long-rooted cultivars such as nantes or imperator. The “baby carrots” sold ready-to-eat in supermarkets are, however, often not from a smaller cultivar of carrot, but are simply full-sized carrots that have been sliced and peeled to make carrot sticks of a uniform shape and size.
Carrot flowers are pollinated primarily by bees. Seed growers use honeybees or mason bees for their pollination needs.
Carrots are used as food plants by the larvae of some Lepidoptera species, including common swift, garden dart, ghost moth, and large yellow underwing.
Food enthusiasts and researchers have developed other varieties of carrots through traditional breeding methods.
One particular variety lacks the usual orange pigment from carotenes, owing its white color to a recessive gene for tocopherol (Vitamin E). Derived from Daucus carota L. and patented (US patent #6,437,222) at the University of Wisconsin-Madison, the variety is intended to supplement the dietary intake of Vitamin E.
In 2005, China was the largest producer of carrots and turnips, according to the Food and Agricultural Organization, although figures from China sometimes are considered suspect. According to these figures, China accounted for at least one third of the global output, followed by Russia and the United States.
Carrots can be eaten raw, whole, chopped, grated, or added to salads for color or texture. They are also often chopped and boiled, fried or steamed, and cooked in soups and stews, as well as fine baby foods and select pet foods. A well known dish is carrots julienne. Grated carrots are used in carrot cakes, as well as carrot puddings, an old English dish thought to have originated in the early 1800s. Together with onion and celery, carrots are one of the primary vegetables used in a mirepoix to make various broths.
The greens are edible as a leaf vegetable, but are rarely eaten by humans.
Since the late 1980s, baby carrots or mini-carrots (carrots that have been peeled and cut into uniform cylinders) have been a popular ready-to-eat snack food available in many supermarkets. Carrot juice is also widely marketed. Baby carrots tend to be very tender, but not as flavorful as full grown carrots (Herbst 2001).
The carrot gets its characteristic orange color from β-carotene, which on consumption by humans is metabolized into vitamin A. Carrots are a rich source of vitamin A, with a 100 gram portion having about five to ten milligrams of carotene (Bender and Bender 2005). Massive overconsumption of carrots can cause hypercarotinemia, a condition in which a person’s skin appears orange (although this is superior to overdose effects of vitamin A, which can cause liver damage).
Carrots are also rich in dietary fiber, antioxidants, and minerals. For best nutrition, the carrot greenery should be removed as soon as possible as it takes moisture and vitamins from the roots (Herbst 2001).
Lack of vitamin A can cause poor vision, and better vision can be restored by adding vitamin A back into the diet. A common urban legend in part based on this is that carrots aid a human being’s night vision. It is believed that this myth partly stemmed from disinformation introduced in 1940 by the British Royal Air Force to cover up the discovery and use of radar technologies that was allowing pilots to be successful at night (Kruszelnicki 2005). It reinforced existing German folklore and helped to encourage children to eat the vegetable.
Ethnomedically, the roots are used to treat digestive problems, intestinal parasites, and tonsilitis.
Falcarinol, a seventeen-carbon diyne fatty alcohol was isolated from carrot and red ginseng (Panax ginseng). It was shown to have potent anticancer properties on primary mammary epithelial cells (breast cancer) (CLC 2007).