Hardy, leafy annual (Spinacia oleracea) of the goosefoot family (Chenopodiaceae), used as a vegetable. The edible leaves, somewhat triangular and either flat or puckered, are arranged in a rosette, from which a seedstalk emerges. Spinach requires cool weather and deep, rich, well-limed soil to give quick growth and maximum leaf area; sowing seed every two weeks from early spring to late summer provides a steady supply. A nutritious vegetable, spinach is rich in iron and vitamins A and C.
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Primitive forms of spinach are found in Nepal and that is probably where the plant was first domesticated. Other than the Indian subcontinent, it was unknown in the ancient world. After the early Muslim conquests the plant spread to other areas. In 647, it was taken to China, possibly by Persians. Muslim Arabs diffused the plant westward up to Islamic Spain. By the eleventh century it was a common plant in the Muslim world.
Spinach is thought to have originated in ancient Persia (Iran). Spinach made its way to China in the 7th century when the king of Nepal sent it as a gift to this country. Spinach has a much more recent history in Europe than many other vegetables. It was only brought to that continent in the 11th century, when the Moors introduced it into Spain. In fact, for a while, spinach was known as "the Spanish vegetable" in England.
Spinach was the favorite vegetable of Catherine de Medici, a historical figure in the 16th century. When she left her home of Florence, Italy, to marry the king of France, she brought along her own cooks, who could prepare spinach the ways that she especially liked. Since this time, dishes prepared on a bed of spinach are referred to as "a la Florentine."
Ultimately, the bioavailability of iron is dependent on its absorption. This is influenced by a number of factors. Iron enters the body in two forms: nonheme iron and heme iron. All of the iron in grains and vegetables, and about three fifths of the iron in animal food sources (meats), is nonheme iron. The much smaller remaining portion from meats is heme iron.
The larger portion of dietary iron (nonheme) is absorbed slowly in its many food sources, including spinach. This absorption may vary widely depending on the presence of binders such as fiber or enhancers, such as vitamin C. Therefore, the body's absorption of non-heme iron can be improved by consuming foods that are rich in vitamin C. However, spinach contains high levels of oxalate. Oxalates bind to iron to form ferrous oxalate, thus making the iron in spinach unavailable, plus high amounts of oxalates remove iron from the body. Therefore, a diet high in oxalate (or phosphate or phytate) leads to a decrease in iron absorption. As a result around 90% of the iron content in Spinach will be released in urine, and not absorbed in the body.
Spinach also has a high calcium content. However, the oxalate content in spinach binds with calcium decreasing its absorption. By way of comparison, the body can absorb about half of the calcium present in broccoli, yet only around 5% of the calcium in spinach. Oxalate is one of a number of factors that can contribute to gout and kidney stones. Equally or more notable factors contributing to calcium stones are: genetic tendency, high intake of animal protein, excess calcium intake, excess vitamin D, prolonged immobility, hyperparathyroidism, renal tubular acidosis, and excess dietary fiber.
Spinach still has a large nutritional value, especially when fresh, steamed, or quickly boiled. It is a rich source of vitamin A (and lutein), vitamin C, vitamin E, vitamin K, magnesium, and several vital antioxidants. Recently, opioid peptides called rubiscolins have also been found in spinach. It is a source of folic acid (Vitamin B9), and this vitamin was first purified from spinach. To benefit from the folate in spinach, it is better to steam it than to boil it. Boiling spinach for four minutes can halve the level of folate.
When cooked, the volume of spinach is decreased by three quarters.
Spinach is an excellent source of vitamin K, vitamin A, manganese, folate, magnesium, iron, vitamin C, vitamin B2, calcium, potassium, and vitamin B6. It is a very good source of dietary fiber, copper, protein, phosphorous, zinc and vitamin E. In addition, it is a good source of omega-3 fatty acids, niacin and selenium.
There are 3 basic types of Spinach:
Spinach is sold loose, bunched, in prepackaged bags, canned, or frozen. Fresh spinach loses much of its nutritional value with storage of more than a few days. While refrigeration slows this effect to about eight days, spinach will lose most of its folate and carotenoid content, so for longer storage it is frozen, cooked and frozen, or canned. Storage in the freezer can be for up to eight months.
Reheating spinach leftovers may cause the formation of poisonous compounds by certain bacteria that thrive on prepared nitrate-rich foods, such as spinach and many other green vegetables. These bacteria can convert the nitrates into nitrites, which may be especially harmful to infants younger than six months. The nitrate-converting enzymes produced by the bacteria can convert even more at elevated temperatures during the second heating. For older children and adults, small concentrations of nitrites are harmless, although formation of nitrosamine compounds from the nitrites could be of concern for adults as well.
The Environmental Working Group reports that spinach is one of the dozen most heavily pesticide-contaminated produce products. The most common pesticides found on spinach are Permethrin, Dimethoate, and DDT.
Spinach, along with brussels sprouts and other green vegetables, is often considered in children's shows to be undesirable.
The United States is the world’s second-largest producer of spinach, with 3 percent of world output, following China (PRC), which accounts for 85 percent of output. A cool-season crop that grows quickly and can withstand hard frosts, spinach is a native of Asia (likely origin in the Persian region) and has been cultivated in China since at least the 7th century. Spinach use was recorded in Europe as early as the mid-13th century, with seed accompanying colonists to the New World.
California (73 percent of 2004-06 U.S. output), Arizona (12 percent), and New Jersey (3 percent) are the top producing states, with 12 other states reporting production of at least 100 acres (2002 census). Over the 2004-06 period, U.S. growers produced an average of 867 million pounds of spinach for all uses, with about three-fourths sold into the fresh-market (includes fresh-cut/processed). According to the 2002 Census of Agriculture, spinach was grown on 1,109 U.S. farms - down 17% from 1997, but about the same number as in 1987.
The farm value of the U.S. spinach crop (fresh and processing) averaged $175 million during 2004-06, with fresh market spinach accounting for 94 percent. The value of fresh market spinach has more than doubled over the past decade as stronger demand has boosted production, while inflation-adjusted prices largely remained constant. California accounts for about three-fourths of the value of both the fresh and processing spinach crops.
Like other cool-season leafy crops, most (about 96 percent) of the fresh spinach consumed in the United States is produced domestically. Although rising, imports (largely from Mexico) totaled about 23 million pounds in 2004-06, compared with 3 million pounds in 1994-06. During the last 10 years, exports (largely to Canada) have jumped 70 percent to 47 million pounds (2004-06), with much of the growth occurring earlier this decade.
Per capita spinach consumption is greatest in the Northeast and Western US. About 80 percent of fresh-market spinach is purchased at retail and consumed at home, while 91 percent of processed spinach is consumed at home. Per capita spinach use is strongest among Asians, highest among women 40 and older, and weakest among teenage girls.
In September 2006, there was an outbreak of disease caused by the E. coli strain H7 in 21 U.S. states. Over a hundred cases were reported, including five deaths. The E. coli was linked to bags of fresh spinach, after which the FDA issued a warning not to eat uncooked fresh spinach or products containing it. The U.S. Food and Drug Administration issued a press release updating the available information. According to the FDA release as on 2006-10-4, 192 cases of E. coli O157:H7 infection have been reported to the Centers for Disease Control and Prevention (CDC) including 30 cases of Hemolytic Uremic Syndrome; there was one death and 98 hospitalizations. The infection affected 26 states. By early 2007, there were 206 illnesses and three deaths attributed to E. coli-tainted spinach.
Based on epidemiological and laboratory evidence, the FDA determined that the implicated spinach originated from an organic spinach field grown by Mission Organics and processed by Natural Selection Foods LLC of San Juan Bautista, California. The FDA speculated that the spinach had been tainted by irrigation water contaminated with wild pig feces because feral pigs were seen in the vicinity of the implicated ranch.
On August 30, 2007, 8,000 cartons of spinach (from Metz Fresh, a King City-based grower and shipper, Salinas Valley, California) were recalled after salmonella was discovered upon routine test. Consumer advocates and some lawmakers complained it exposed big gaps in food safety, even if 90% of suspect vegetable didn’t reach the shelves.
In Indonesia, the word bayam is applied both to certain species of amaranth commonly eaten as a leafy vegetable, and to spinach, which is rarely seen, only in certain supermarkets but well known from Popeye cartoons.Unrelated species