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== Culinary ==
== Culinary ==


Dandelion leaves and buds have been a part of traditional Mediterranean (especially Sephardic <ref>http://www.inmamaskitchen.com/RECIPES/RECIPES/Soups/dandelion_soup.html</ref> <ref>http://www.ecookbooks.com/p-95-mediterranean-herb-cookbook.aspx</ref> <ref>http://search.barnesandnoble.com/Cooking-Weeds/Vivien-Weise/e/9781903018309</ref>) and Asian, most notably Chinese and Korean, cuisine <ref>http://www.foodinkorea.org/eng_food/korfood/korfood2_1.jsp</ref> <ref>http://cat.inist.fr/?aModele=afficheN&cpsidt=850767</ref>. Also the roasted, ground root are sometimes used as a caffiene free coffee substitute. Once a popular salad green in these regions, dandelion leaves are becoming popular worldwide in restaurants, in braised and salad dishes, and are not difficult to find at farmers markets in the spring and summer. The dandelion plant is truly a weed in the classical sense: "a plant for which we once knew the use but we've forgotten it" <ref>http://www.nj.com/entertainment/dining/index.ssf/2008/04/dandelion_as_underrated_as_und.html</ref>.
Dandelion leaves and buds have been a part of traditional Mediterranean (especially Sephardic <ref>http://www.inmamaskitchen.com/RECIPES/RECIPES/Soups/dandelion_soup.html</ref> <ref>http://www.ecookbooks.com/p-95-mediterranean-herb-cookbook.aspx</ref> <ref>http://search.barnesandnoble.com/Cooking-Weeds/Vivien-Weise/e/9781903018309</ref>) and Asian, most notably Chinese and Korean, cuisine <ref>http://www.foodinkorea.org/eng_food/korfood/korfood2_1.jsp</ref> <ref>http://cat.inist.fr/?aModele=afficheN&cpsidt=850767</ref>. Also the roasted, ground root are sometimes used as a caffeine free coffee substitute. Once a popular salad green in these regions, dandelion leaves are becoming popular worldwide in restaurants, in braised and salad dishes, and are not difficult to find at farmers markets in the spring and summer. The dandelion plant is truly a weed in the classical sense: "a plant for which we once knew the use but we've forgotten it" <ref>http://www.nj.com/entertainment/dining/index.ssf/2008/04/dandelion_as_underrated_as_und.html</ref>.


== Nutritional properties ==
== Nutritional properties ==

Revision as of 13:06, 6 July 2009

"Dandelion" redirects here. For other uses, see Dandelion (disambiguation).

Dandelion
A dandelion flower (top) and parachute ball (bottom)
Scientific classification
Kingdom:
Plantae
(unranked):
Angiosperms
(unranked):
Eudicots
(unranked):
Asterids
Order:
Asterales
Family:
Asteraceae
Tribe:
Cichorieae
Genus:
Taraxacum

Species

See text

Taraxacum is a large genus of flowering plants in the family Asteraceae. They are native to Europe and Asia, and two species, T. officinale and T. erythrospermum, are found as weeds worldwide.[1] The common name Dandelion (Template:Pron-en (DAN-dih-ly-un) is given to members of the genus and like other members of the Asteraceae family, they have very small flowers collected together into a composite flower head. Each single flower in a head is called a floret. Many Taraxacum species produce seeds asexually by apomixis, where the seeds are produced without pollination, resulting in offspring that are genetically identical to the parent plant.[2]

Description

A dandelion flower head composed of hundreds of smaller florets.

The species of Taraxacum are tap-rooted biennial or perennial herbaceous plants, native to temperate areas of the Old World.

The leaves are 5–25 cm long or longer, simple and basal, entire or lobed, forming a rosette above the central taproot. The flower heads are yellow to orange colored, and are open in the daytime but closed at night. The heads are borne singly on a hollow stem (scape) which rises 4–75 cm[3] above the leaves and exudes a milky sap (latex) when broken. A rosette may produce several flowering stems at a time. The flower heads are 2–5 cm in diameter and consists entirely of ray florets. The flower heads mature into a spherical "clocks"[citation needed] (also known as a "wishie"[citation needed]) containing many single-seeded fruits called achenes. Each achene is attached to a pappus of fine hairs, which enable wind-aided dispersal over long distances.

A dandelion flower in the closing state.

The flower head is surrounded by bracts (sometimes mistakenly called sepals) in two series. The inner bracts are erect until the seeds mature, then flex downward to allow the seeds to disperse; the outer bracts are always reflexed downward. Some species drop the "parachute" from the achenes; the hair-like parachutes are called pappus, and they are modified sepals. Between the pappus and the achene, there is a stalk called a beak, which elongates as the fruit matures. The beak breaks off from the achene quite easily, separating the seed from the parachute.

Dandelion leaves are believed to have a diuretic effect as they increase salt and water excretion from the kidneys[4].

Taxonomy

The genus is taxonomically complex, with some botanists dividing the group into numerous macrospecies, and many more microspecies: approximately 235 apomictic and polyploid microspecies have been recorded in Great Britain and Ireland.[5] Some botanists take a much narrower view and only accept a total of about 60 species.[6]

Selected species

Seed dispersal

A number of species of Taraxacum are regarded as seed dispersed weeds or ruderals, especially the Common dandelion (T. officinale), which has been introduced over much of the temperate world as a lawn weed. After pollination and flowering is finished, the dandelion flower dries out for a day or two and then the seed-bearing parachutes expand and lift out of the dried flower head. The dried part of the flower drops off and the parachute ball opens into a full sphere. The parachute drops off when the seed strikes an obstacle. Often dandelions are observed growing in crevices near a wall; when the blowing fruits hit the wall, the feathery pappi comes off, dropping the dandelion seeds to the base of the wall or into a crevice. After the seed is released, the parachutes lose their feathered structure and take on a fuzzy, cotton-like appearance, often called "dandelion snow".

Dandelions are used as food plants by the larvae of some species of Lepidoptera (butterflies and moths). See List of Lepidoptera that feed on dandelions.

Away from their native regions, some dandelion species have become established in the Americas, Australia, and New Zealand, and are now common throughout all temperate regions, Taraxacum officinale has become a nearly world wide weed.

False dandelions

Hawksbeard flower heads and ripe seeds are sometimes confused with Dandelions.

Dandelions are so similar to catsears (Hypochaeris) that catsears are also known as "false dandelions". Both plants carry similar flowers which form into windborne seeds. However, dandelion flowers are borne singly on unbranched, hairless and leafless, hollow stems, while catsear flowering stems are branched, solid and carry bracts. Both plants have a basal rosette of leaves and a central taproot. However, the leaves of dandelions are smooth or glabrous, whereas those of catsears are coarsely hairy.

Other plants with superficially similar flowers include hawkweeds (Hieracium) and hawksbeards (Crepis). These are both readily distinguished by their branched flowering stems which are usually hairy and bear leaves.

History

Dandelions are thought to have evolved about thirty million years ago in Eurasia[8]; they have been used by humans for food and as a herb for much of recorded history[citation needed]. They were introduced to North America by early European immigrants.

Origin of the name

The English name dandelion is a corruption of the French dent de lion[9] meaning "lion's tooth", referring to the coarsely toothed leaves. The names of the plant have the same meaning in several other European languages, such as the Italian dente di leone, Spanish diente de león, Portuguese dente-de-leão, Norwegian Løvetann, and German Löwenzahn.[citation needed]

In modern French the plant is named pissenlit, which means "piss in bed", apparently referring to its diuretic properties[citation needed]. Likewise, "pissabeds" is an English folk-name for this plant, as is piscialletto in Italian and the Spanish meacamas.[citation needed] In various north-eastern Italian dialects the plant is known as pisacan ("dog pisses"), referring to how common they are found at the side of pavements[citation needed].

In several European languages the plant, or at least its parachute ball stage, is named after the popular children's pastime of blowing the parachutes off the stalk: Pusteblume (German for "blowing flower"), soffione (Italian for "blowing"; in some northern Italian dialects), dmuchawiec (Polish, derived from the verb "blow"), одуванчик (Russian, derived from the verb "blow"). [citation needed]

In other languages the plant is named after the white sap found in its stem, e.g. Mlecz (derived from the Polish word for "milk"), kutyatej (Hungarian for "dog milk"), маслачак (derived from the Serbian word маслац, meaning "butter")).[citation needed] Also the Lithuanian name kiaulpienė can be translated as "sow milk"[citation needed], and similarly, in Latvian it is called 'pienene, the word being derived from piens - milk [citation needed].

The alternative Hungarian name gyermekláncfű ("child's chain grass"), refers to the habit of children to pick dandelions, remove the flowers, and make links out of the stems by "plugging" the narrow top end of the stem into the wider bottom end.[citation needed] In Turkish the dandelion is called karahindiba meaning "black endive".[citation needed] In Swedish, it is called maskros ("worm rose") [citation needed]. In Finnish and Estonian, it is called voikukka and võilill, respectively, meaning "butter flower", referring to its buttery colour.[citation needed] In Dutch it is called paardebloem, meaning "horse-flower".[citation needed] In Chinese it is called "蒲公英" (pronounced pu gong ying), meaning flower that grows in public spaces by the riverside.[citation needed]


Culinary

Dandelion leaves and buds have been a part of traditional Mediterranean (especially Sephardic [10] [11] [12]) and Asian, most notably Chinese and Korean, cuisine [13] [14]. Also the roasted, ground root are sometimes used as a caffeine free coffee substitute. Once a popular salad green in these regions, dandelion leaves are becoming popular worldwide in restaurants, in braised and salad dishes, and are not difficult to find at farmers markets in the spring and summer. The dandelion plant is truly a weed in the classical sense: "a plant for which we once knew the use but we've forgotten it" [15].

Nutritional properties

Dandelion leaves contain abundant amounts of vitamins and minerals, especially Vitamins A, C and K, and are good sources of calcium (0.19% net weight), potassium (0.4% net weight) and fair amounts of iron and manganese [16], higher than similar leafy greens such as spinach. They contain 15% protein and 73% carbohydrates, 37% of which is fiber (27% of the leaves are fiber) [17]. The leaves also contain smaller amounts of over two dozen other nutrients, and are a significant source of beta carotene (0.03% net weight), lutein and zeaxanthin (combined 0.066% net weight) [18]. A cup of dandelion leaves contains 112% daily recommendation of vitamin A, 32% of vitamin C, and 535% of vitamin K and 218 mg potassium, 103 mg calcium, and 1.7 mg of iron[19].


Medicinal Uses

Dandelions, flowers, roots and leaves, have been used for centuries in traditional Chinese medicine & medicinal teas, most notably for liver detoxification, as a natural diuretic and inflammation reduction [20]. Unlike other diuretics, dandelion leaves contain good amounts of potassium, a mineral that is often lost during increased micturition. There is also evidence that this property of dandelion leaves may normalize blood sugar [21].

Antioxidant

Dandelion flowers contains luteolin, an antioxidant, and has demonstrated antioxidant properties without cytotoxicity.[22][23]


Caffeic acid and carcinogenicity

Dandelion contains Caffeic acid, as a secondary plant metabolite, which may be carcinogenic; however, there have been no known ill effects of caffeic acid in humans and acts as a carcinogenic inhibitor. [24][25]

Bees

Dandelions are important plants for bees. Not only is their flowering used as an indicator that the honey bee season is starting,[citation needed] but they are also an important source of nectar and pollen early in the season.[citation needed]


Dandelion pollen is a common allergen and is a common component in bee pollen [26]. This allergen may be commonly responsible for asthma, allergic rhinitis, allergic conjunctivitis and contact dermatitis in sensitive individuals.

Pearl bordered Fritillary

They are also used as a source of nectar by the Pearl-bordered Fritillary (Boloria euphrosyne), one of the earliest emerging butterflies in the spring.

Gallery

See also

References

  1. ^ "Taraxacum". Flora of North America.
  2. ^ Dandelion - J. Doll and T. Trower
  3. ^ Taraxacum latilobum in Flora of North America @ efloras.org
  4. ^ University of Maryland, complimentary medicine
  5. ^ Richards, A.J. (1997). Dandelions of Great Britain and Ireland (Handbooks for Field Identification). BSBI Publications. p. 330. ISBN 978-0901158253.
  6. ^ http://www.jstor.org/pss/2430530
  7. ^ "Plants for a future: Taraxacum kok-saghiz".
  8. ^ Gardening in Western Washington: Dandelions
  9. ^ S. Potter & L. Sargent (1973) Pedigree: essays on the etymology of words from nature. Collins New Naturalist series Volume 56
  10. ^ http://www.inmamaskitchen.com/RECIPES/RECIPES/Soups/dandelion_soup.html
  11. ^ http://www.ecookbooks.com/p-95-mediterranean-herb-cookbook.aspx
  12. ^ http://search.barnesandnoble.com/Cooking-Weeds/Vivien-Weise/e/9781903018309
  13. ^ http://www.foodinkorea.org/eng_food/korfood/korfood2_1.jsp
  14. ^ http://cat.inist.fr/?aModele=afficheN&cpsidt=850767
  15. ^ http://www.nj.com/entertainment/dining/index.ssf/2008/04/dandelion_as_underrated_as_und.html
  16. ^ http://www.nutritiondata.com/facts/vegetables-and-vegetable-products/2441/2
  17. ^ http://caloriecount.about.com/calories-dandelion-greens-i11207
  18. ^ http://www.healthrecipes.com/dandelion.htm
  19. ^ http://www.naturalnews.com/025913.html
  20. ^ http://www.naturalnews.com/025913.html
  21. ^ http://www.umm.edu/altmed/articles/dandelion-000236.htm
  22. ^ Chun Hu and David D. Kitts. Food, Nutrition and Health, Faculty of Agricultural Sciences, University of British Columbia, Vancouver, BC, Canada. October 2004. Luteolin and luteolin-7-O-glucoside from dandelion flower suppress iNOS and COX-2 in RAW264.7 cells. Springer Netherlands. 245:1-2(107-113).
  23. ^ Luteolin and luteolin-7-O-glucoside from dandelion flower suppress iNOS and COX-2 in RAW264.7 cells
  24. ^ Caffeic Acid Metabolism by Gnotobiotic Rats and their Intestinal Bacteria
  25. ^ Chlorogenic Acid Bioavailability Largely Depends on Its Metabolism by the Gut Microflora in Rats
  26. ^ http://www.immunocapinvitrosight.com/dia_templates/ImmunoCAP/Allergen____28012.aspx

External links

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