Beta vulgaris

Beta vulgaris (beet) is a plant in the Amaranthaceae family (which is now included in Betoideae subfamily).^{[1][2][3][4][5]} It has numerous cultivated varieties, the most well known of which is the root vegetable known as the beetroot or garden beet. Other cultivated varieties include the leaf vegetable chard; the sugar beet, used to produce table sugar; and mangelwurzel, which is a fodder crop. Three subspecies are typically recognised. All cultivated varieties fall into the subspecies Beta vulgaris subsp. vulgaris. Beta vulgaris subsp. maritima, commonly known as the sea beet, is the wild ancestor of these and is found throughout the Mediterranean, the Atlantic coast of Europe, the Near East, and India. A second wild subspecies, Beta vulgaris subsp. adanensis, occurs from Greece to Syria.

The roots are most commonly deep red-purple in color, but less common varieties include golden yellow and red-and-white striped roots.^[6]

Beta vulgaris is an herbaceous biennial or, rarely, perennial plant with leafy stems growing to 1–2 m tall. The leaves are heart-shaped, 5–20 cm long on wild plants (often much larger in cultivated plants). The flowers are produced in dense spikes; each flower is very small, 3–5 mm diameter, green or tinged reddish, with five petals; they are wind pollinated. The fruit is a cluster of hard nutlets.

Taxonomy

The taxonomy of the various wild and cultivated races of beets has a long and complicated history. Mansfeld's Encyclopedia of Agricultural and Horticultural Crops following Letschert's 1993 treatment of Beta, section Beta recognizes the following taxa^[7] for cultivated varieties, which are grown for their taproots, leaves, or swollen midribs:

• B. v. ssp. vulgaris convar. cicla (leaf beet or chard) - The leaf beet group has a long history dating to the second millennium BC. The first cultivated forms were believed to have been domesticated in the Mediterranean, but were introduced to the Middle East, India, and finally China by 850 AD. These were used as medicinal plants in Ancient Greece and Medieval Europe. Their popularity declined in Europe following the introduction of spinach.
  • B. v. ssp. v. convar. cicla. var. cicla (spinach beet) - This variety is widely cultivated for its leaves, which are usually cooked like spinach. It can be found in many grocery stores around the world.
  • B. v. ssp. v. convar. cicla. var. flavescens (Swiss chard) - Chard leaves have thick and fleshy midribs. Both the midribs and the leaf blades are used as vegetables, often in separate dishes. Some cultivars are also grown ornamentally for their coloured midribs. The thickened midribs are thought to have arisen from the spinach beet by mutation.
• B. v. ssp. vulgaris convar. vulgaris (tuberous beets) - This grouping contains all beets grown for their thickened tubers rather than their leaves.
  • B. v. ssp. v. convar. vulgaris var. crassa (mangelwurzel) - This variety was developed in the 18th century for its tubers for use as a fodder crop.
  • B. v. ssp. v. convar. vulgaris var. altissima (sugar beet) - The sugar beet is a major commercial crop due to its high concentrations of sucrose, which is extracted to produce table sugar. It was developed in Germany in the late 18th century after the roots of beets were found to contain sugar in 1747.
  • B. v. ssp. v. convar. vulgaris var. vulgaris (beetroot or garden beet) - This is the red root vegetable that is most typically associated with the word 'beet'. It is especially popular in Eastern Europe where it is the main ingredient of borscht.

Ecology

Beets are a food plant for the larvae of a number of Lepidoptera species.

Uses

Food

Spinach beet leaves are eaten as a pot herb. Young leaves of the garden beet are sometimes used similarly. The midribs of Swiss chard are eaten boiled while the whole leaf blades are eaten as spinach beet.

In some parts of Africa, the whole leaf blades are usually prepared with the midribs as one dish.^[8]

The leaves and stems of young plants are steamed briefly and eaten as a vegetable; older leaves and stems are stir-fried and have a flavour resembling taro leaves.

The usually deep-red roots of garden beet can be baked, boiled, or steamed, and often served hot as a cooked vegetable or cold as a salad vegetable. They are also pickled. Raw beets are added to salads. A large proportion of the commercial production is processed into boiled and sterilised beets or into pickles. In Eastern Europe beet soup, such as cold borsch, is a popular dish. Yellow-coloured garden beets are grown on a very small scale for home consumption.^[8]

The consumption of beets causes pink urine in some people.

Jews traditionally eat beet on Rosh Hashana (New Year). Its Aramaic name סלקא sounds like the word for "remove" or "depart"; it is eaten with a prayer "that our enemies be removed".^[9]

Nutrition

Beets, raw Nutritional value per 100 g (3.5 oz) Energy 180 kJ (43 kcal) Carbohydrates 9.56 g Sugars 6.76 g Dietary fiber 2.8 g Fat 0.17 g Protein 1.61 g Vitamins Vitamin A equiv. beta-carotene (0%) 2 μg (0%) 20 μg Thiamine (B1) (3%) 0.031 mg Riboflavin (B2) (3%) 0.04 mg Niacin (B3) (2%) 0.334 mg Pantothenic acid (B5) (3%) 0.155 mg Vitamin B6 (5%) 0.067 mg Folate (B9) (27%) 109 μg Vitamin C (6%) 4.9 mg Trace metals Calcium (2%) 16 mg Iron (6%) 0.8 mg Magnesium (6%) 23 mg Manganese (16%) 0.329 mg Phosphorus (6%) 40 mg Potassium (7%) 325 mg Sodium (5%) 78 mg Zinc (4%) 0.35 mg Other constituents Water 87.58g Link to USDA Database entry Units μg = micrograms • mg = milligrams IU = International units Percentages are roughly approximated using US recommendations for adults. Source: USDA Nutrient Database

Beets are low in calories (about 45 kcal per 100 g) and have zero cholesterol and a minute amount of fat. Nutrition comes from the beets' vitamins, minerals, and unique plant-derived anti-oxidants.

A phytochemical compound, glycine betaine, is found in the root. Betaine lowers the chance of coronary heart disease (CHD), stroke, and peripheral vascular diseases. Beets in raw form are high in folates. Folates are essential in the synthesis of DNA within cells. Vitamin-C is found in small amounts.

The root provides B-complex vitamins including niacin (B-3), pantothenic acid (B-5), and pyridoxine (B-6), and minerals such as iron, manganese, copper, magnesium, and potassium, lowers the heart rate and regulates metabolism in the cells.

Beet greens contain vitamin C, carotenoids, flavonoid anti-oxidants, and vitamin-A.^[10]

Medicine

The roots and leaves of the beet have been used in folk medicine to treat a wide variety of ailments.^[8] Ancient Romans used beetroot as a treatment for fevers and constipation, amongst other ailments. Apicius in De re coquinaria gives five recipes for soups to be given as a laxative, three of which feature the root of beet.^[11] Hippocrates advocated the use of beet leaves for binding wounds. Since Roman times, beetroot juice has been considered an aphrodisiac. From the Middle Ages, beetroot was used as a treatment for a variety of conditions, especially those relating to digestion and the blood. Platina recommended taking beetroot with garlic to nullify the effects of 'garlic-breath'.^[12] Beta vulgaris beets have been used in traditional Austrian medicine internally (directly or as juice) and externally (as compresses) for treatment of disorders of the respiratory tract, fevers, and infections.^[13]

It has been suggested the pigment molecule betanin in the root of red beets may protect against oxidative stress and has been used for this purpose in Europe for centuries.^[14]

All parts of the beet plant contain oxalic acid. Beet greens and Swiss chard are both considered high oxalate foods which have been implicated on the formation of kidney stones.

Other uses

Cultivars with large, brightly coloured leaves are grown for decorative purposes.^[8]

Cultivation

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Beet seeds

Beets are cultivated for fodder (e.g. mangelwurzel), for sugar (the sugar beet), as a leaf vegetable (chard or "Bull's Blood"), or as a root vegetable ("beetroot", "table beet", or "garden beet").

"Blood Turnip" was once a common name for beet root cultivars for the garden. Examples include: Bastian's Blood Turnip, Dewing's Early Blood Turnip, Edmand Blood Turnip, and Will's Improved Blood Turnip.^[15]

The "earthy" taste of some beetroot cultivars comes from the presence of geosmin. Researchers have not yet answered whether beets produce geosmin themselves or whether it is produced by symbiotic soil microbes living in the plant.^[16] Breeding programs can produce cultivars with low geosmin levels yielding flavours more acceptable to consumers.^[17]

Beets are one of the most boron-intensive of modern crops, a dependency possibly introduced as an evolutionary response its pre-industrial ancestor's constant exposure to sea spray; on commercial farms, a 60 tonne per hectare (26.8 ton/acre) harvest requires 600 grams of elemental boron per hectare (8.6 ounces/acre) for growth.^[18] A lack of boron causes the meristem and the shoot to languish, eventually leading to heart rot.^[18]

Red or purple coloring

The color of red/purple beetroot is due to a variety of betalain pigments, unlike most other red plants, such as red cabbage, which contain anthocyanin pigments. The composition of different betalain pigments can vary, resulting in strains of beetroot which are yellow or other colors in addition to the familiar deep red.^[19] Some of the betalains in beets are betanin, isobetanin, probetanin, and neobetanin (the red to violet ones are known collectively as betacyanin). Other pigments contained in beet are indicaxanthin and vulgaxanthins (yellow to orange pigments known as betaxanthins). Indicaxanthin has been shown as a powerful protective antioxidant for thalassemia and prevents the breakdown of alpha-tocopherol (Vitamin E).

Betacyanin in beetroot may cause red urine in people who are unable to break it down. This is called beeturia.^[20]

The pigments are contained in cell vacuoles. Beetroot cells are quite unstable and will 'leak' when cut, heated, or when in contact with air or sunlight. This is why red beetroots leave a purple stain. Leaving the skin on when cooking, however, will maintain the integrity of the cells and therefore minimize leakage.

History

The sea beet, the ancestor of modern cultivated beets, prospered along the coast of the Mediterranean Sea. Beetroot remains have been excavated in the Third dynasty Saqqara pyramid at Thebes, Egypt, and four charred beetroots were found in the Neolithic site of Aartswoud in the Netherlands though it has not been determined whether these were domesticated or wild forms of B. vulgaris. Zohary and Hopf note that beetroot is "linguistically well identified." They state the earliest written mention of the beet comes from 8th century BC Mesopotamia.^[21] The Greek Peripatetic Theophrastus later describes the beet as similar to the radish, while Aristotle also mentions the plant.^[21][22] Available evidence, such as that provided by Aristotle and Theophrastus, suggests the leafy varieties of the beet were grown primarily for most of its history, though these lost much of their popularity following the introduction of spinach. The ancient Romans considered beets an important health food and an aphrodisiac.^[6]

Roman and Jewish literary sources suggest that in the 1st century BC the domestic beet was represented in the Mediterranean basin primarily by leafy forms like chard and spinach beet.^[21] Zohary and Hopf also argue that it is very probable that beetroot cultivars were also grown at the time, and some Roman recipes support this.^[21][22] Later English and German sources show that beetroots were commonly cultivated in Medieval Europe.^[22]

The sugar beet

Modern sugar beets date back to mid-18th century Silesia where the king of Prussia subsidised experiments aimed at processes for sugar extraction.^[22][23] In 1747 Andreas Marggraf isolated sugar from beetroots and found them at concentrations of 1.3-1.6%.^[7] He also demonstrated that sugar could be extracted from beets that was the same as that produced from sugarcane.^[23] His student, Franz Karl Achard, evaluated 23 varieties of mangelwurzel for sugar content and selected a local race from Halberstadt in modern-day Saxony-Anhalt, Germany. Moritz Baron von Koppy and his son further selected from this race for white, conical tubers.^[7] The selection was named 'Weiße Schlesische Zuckerrübe', meaning white Silesian sugar beet, and boasted about a 6% sugar content.^[7][22] This selection is the progenitor of all modern sugar beets.^[7]

A royal decree led to the first factory devoted to sugar extraction from beetroots being opened in Kunern, Silesia (now Konary, Poland) in 1801. The Silesian sugar beet was soon introduced to France where Napoleon opened schools specifically for studying the plant. He also ordered that 28,000 hectares (69,000 acres) be devoted to growing the new sugar beet.^[22] This was in response to British blockades of cane sugar during the Napoleonic Wars, which ultimately stimulated the rapid growth of a European sugar beet industry.^[22][23] By 1840 about 5% of the world's sugar was derived from sugar beets, and by 1880 this number had risen more than tenfold to over 50%.^[22] The sugar beet was introduced to North America after 1830 with the first commercial production starting in 1879 at a farm in Alvarado, California.^[7][23] The sugar beet was also introduced to Chile via German settlers around 1850.^[7]

It remains a widely cultivated commercial crop for producing table sugar.

References

External links

Wikimedia Commons has media related to Beet.

Wikisource has the text of the 1911 Encyclopædia Britannica article Beet.

• Cultural Information on Beets for the Home Garden
• PROTAbase on Beta vulgaris
• Beta vulgaris craca - Plants For a Future Database entry
• Stephen Nottingham (2004). Beetroot (e-book). 
• Sorting Beta names - multilingual listing of the Beta species