Spinach (Spinacia oleracea) is a leafy green flowering plant native to central and Western Asia. It is of the order Caryophyllales, family Amaranthaceae, subfamily Chenopodioideae. Its leaves are a common edible vegetable consumed either fresh, or after storage using preservation techniques by canning, freezing, or dehydration. It may be eaten cooked or raw, and the taste differs considerably; the high oxalate content may be reduced by steaming.
It is an annual plant (rarely biennial), growing as tall as 30 cm (1 ft). Spinach may overwinter in temperate regions. The leaves are alternate, simple, ovate to triangular, and very variable in size: 2–30 cm (1–12 in) long and 1–15 cm (0.4–5.9 in) broad, with larger leaves at the base of the plant and small leaves higher on the flowering stem. The flowers are inconspicuous, yellow-green, 3–4 mm (0.1–0.2 in) in diameter, and mature into a small, hard, dry, lumpy fruit cluster 5–10 mm (0.2–0.4 in) across containing several seeds.
Common spinach (S. oleracea) was long considered to be in the family Chenopodiaceae, but in 2003 that family was merged into the Amaranthaceae in the order Caryophyllales. Within the family Amaranthaceae sensu lato, Spinach belongs to the subfamily Chenopodioideae.
Pollination occurs via wind anemophily, because the flowers are small and green and thus they are unattractive to pollinators. Therefore, the pollen evolved to be very small and light so it can be transported to large distances, often miles away.
Spinach male flowers
Spinach female flowers
Round seeds of the 'Monnopa' cultivar
Spiky seeds of the 'Erste Ernte' cultivar
Spinach is thought to have originated about 2,000 years ago in ancient Persia from which it was introduced to India and later to ancient China via Nepal in 647 AD as the "Persian vegetable". In AD 827, the Saracens introduced spinach to Sicily. The first written evidence of spinach in the Mediterranean was recorded in three 10th-century works: a medical work by al-Rāzī (known as Rhazes in the West) and in two agricultural treatises, one by Ibn Waḥshīyah and the other by Qusṭus al-Rūmī. Spinach became a popular vegetable in the Arab Mediterranean and arrived in Spain by the latter part of the 12th century, where Ibn al-ʻAwwām called it raʼīs al-buqūl, 'the chieftain of leafy greens'. Spinach was also the subject of a special treatise in the 11th century by Ibn Ḥajjāj.[better source needed]
Spinach first appeared in England and France in the 14th century, probably via Spain, and gained common use because it appeared in early spring when fresh local vegetables were not available. Spinach is mentioned in the first known English cookbook, the Forme of Cury (1390), where it is referred to as 'spinnedge' and 'spynoches'. During World War I, wine fortified with spinach juice was given to injured French soldiers with the intent to curtail their bleeding.
Consumption and nutrition
Spinach is eaten both raw, in salads, and cooked in soups, curries, or casseroles.
|Nutritional value per 100 g (3.5 oz)|
|Energy||97 kJ (23 kcal)|
|Dietary fiber||2.2 g|
|Vitamin A equiv.|
|Vitamin A||9377 IU|
|†Percentages are roughly approximated using US recommendations for adults. |
Source: USDA FoodData Central
Raw spinach is 91% water, 4% carbohydrates, 3% protein, and contains negligible fat. In a 100 g (3.5 oz) serving providing only 23 calories, spinach has a high nutritional value, especially when fresh, frozen, steamed, or quickly boiled. It is a rich source (20% or more of the Daily Value, DV) of vitamin A, vitamin C, vitamin K, magnesium, manganese, iron and folate. Spinach is a moderate source (10–19% of DV) of the B vitamins, riboflavin and vitamin B6, vitamin E, calcium, potassium, and dietary fiber (table).
100 g of spinach contains over four times the recommended daily intake of vitamin K. For this reason, individuals taking the anticoagulant warfarin, which acts by inhibiting vitamin K, are instructed to minimize consumption of spinach (and other dark green leafy vegetables) to avoid blunting the effect of warfarin.
Although spinach contains moderate amounts of iron and calcium, it also contains oxalates, which may inhibit absorption of calcium and iron in the stomach and small intestine. Cooked spinach has lower levels of oxalates, and its nutrients may be absorbed more completely.
Cooking spinach significantly decreases its vitamin C concentration, as vitamin C is degraded by heating. Folate levels may also be decreased, as folate tends to leach into cooking liquid.
(millions of tonnes)
|Source: UN Food and Agriculture Organization, Statistics Division|
Marketing and safety
Fresh spinach is sold loose, bunched, or packaged fresh in bags. Fresh spinach loses much of its nutritional value with storage of more than a few days. Fresh spinach is packaged in air, or in nitrogen gas to extend shelf life. While refrigeration slows this effect to about eight days, fresh spinach loses most of its folate and carotenoid content over this period of time. For longer storage, it is canned, or blanched or cooked and frozen.
Some packaged spinach is exposed to radiation to kill any harmful bacteria. The Food and Drug Administration approves of irradiation of spinach leaves up to 4.0 kilograys, having no or only a minor effect on nutrient content.
In popular culture
The comics and cartoon character Popeye the Sailor Man is portrayed as gaining strength by consuming canned spinach. The accompanying song lyric is: "I'm strong to the finich [sic], 'cuz I eats me spinach." This is usually attributed to the iron content of spinach, but in a 1932 strip, Popeye states that "spinach is full of vitamin A" and that is what makes people strong and healthy.
- Green leafy vegetable
- Ipomoea aquatica
- Mountain spinach
- Palmer amaranth
- Spinach dip
- Spinach in the United States
- Spinach salad
- Spinach soup
- Tetragonia tetragonioides
- White goosefoot
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- Julia Cresswell (9 September 2010). Oxford Dictionary of Word Origins. OUP Oxford. p. 415. ISBN 978-0-19-954793-7.
- "Spinach". Online Etymology Dictionary, Douglas Harper. 2019. Retrieved 6 March 2019.
- "Caryophyllales". www.mobot.org. Retrieved 2020-12-02.
- Pam Dawling (1 February 2013). Sustainable Market Farming: Intensive Vegetable Production on a Few Acres. New Society Publishers. pp. 244–. ISBN 978-1-55092-512-8.
- Rubatzky, Vincent E.; Yamaguchi, Mas (1997), Rubatzky, Vincent E.; Yamaguchi, Mas (eds.), "Spinach, Table Beets, and Other Vegetable Chenopods", World Vegetables: Principles, Production, and Nutritive Values, Boston, MA: Springer US, pp. 457–473, doi:10.1007/978-1-4615-6015-9_21, ISBN 978-1-4615-6015-9, retrieved 2021-06-11
- Birlouez, Éric (2020). "Une fabuleuse diversité, «L'épinard, légume de carème»" [A fabulous diversity, «Spinach, the lent vegetable»]. Petite et grande histoire des légumes [A small and great history of vegetables]. Carnets de sciences (in French) (1 ed.). Versailles/impr. en Suisse: Quæ. p. 52-54. ISBN 978-2-7592-3196-6. Quæ
- "Spinach history - origins of different types of spinach". Vegetable Facts. 2019. Retrieved 2 November 2019.
- Rolland, Jacques L.; Sherman, Carol (2006). The Food Encyclopedia. Toronto: Robert Rose. pp. 335–338. ISBN 9780778801504.
- Ibn al-ʻAwwām, Yaḥyá ibn Muḥammad (1802). "23.8". Kitāb al-Filāḥah. Retrieved July 30, 2014.
- Clifford A. Wright. Mediterranean Vegetables: A Cook's ABC of Vegetables and their Preparation in Spain, France, Italy, Greece, Turkey, the Middle East, and North Africa, with More than 200 Authentic Recipes for the Home Cook. (Boston: Harvard Common Press, 2001). pp. 300-301.
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- Margaret Grieve; Maud Grieve (1 June 1971). A modern herbal: the medicinal, culinary, cosmetic and economic properties, cultivation and folk-lore of herbs, grasses, fungi, shrubs, & trees with all their modern scientific uses. Courier Dover Publications. pp. 761–. ISBN 978-0-486-22799-3. Retrieved 13 August 2010.
- Sheps SG (19 April 2018). "Warfarin diet: What foods should I avoid?". Mayo Clinic. Retrieved 6 March 2019.
- "Osteoporosis Diet & Nutrition: Foods for Bone Health". National Osteoporosis Foundation. 2015-12-21. Retrieved 2019-11-18.
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- Delchier, N; Reich, M; Renard, C.M.G.C. (December 2012). "Impa.ct of cooking methods on folates, ascorbic acid and lutein in green beans (Phaseolus vulgaris) and spinach (Spinacea oleracea)". Food Science and Technology. Elsevier. 49 (2): 197–201. doi:10.1016/j.lwt.2012.06.017.
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- Pennsylvania State University (23 March 2005). "Storage time and temperature effects nutrients in spinach". ScienceDaily. Retrieved 5 July 2008.
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- "ToxGuide for cadmium" (PDF). Atlanta, GA: Agency for Toxic Substances and Disease Registry, US Department of Health and Human Services. October 2012.
- Gabbatt, Adam (8 December 2009). "E.C. Segar, Popeye's creator, celebrated with a Google doodle". The Guardian. Retrieved 5 May 2010.
- Holloway, Diane (2001). American History in Song: Lyrics from 1900 to 1945. Authors Choice Press. p. 294. ISBN 978-0-595-19331-8. Retrieved 18 November 2022.
- Joe Schwarcz, Monkeys, Myths, and Molecules: Separating Fact from Fiction in the Science of Everyday Life, 2015, ISBN 1770411917, p. 245; spinach actually contains beta-carotene, which the body converts to vitamin A