Rediscovering Rhubarb

Rhubarb (Rheum rhabarbarum) is a species of plant in the family Polygonaceae, along with sorrel and buckwheat. According to the The Treasury of Botany, edited  by John Lindley and Thomas Moore in 1866, the technical name of the genus (Rheum) is derived from Rha, the ancient name of the Volga, on whose banks the plants grow. There were those who called it Rha Ponticum, and others Rheum or Rha-barbarum. Others derive the name from the Greek rheo (‘to flow’), in allusion to the laxative properties of the root.

Rhubarb has been used for medical purposes by the Chinese for thousands of years, and appears in The Divine Farmer’s Herb-Root Classic, which legend attributes to the mythical Shen Nung, the Yan Emperor, and is thought to have been compiled about 2700 years ago. Pedanius Dioscorides (circa 40—90 AD) was a Greek who served in Rome as the chief physician of Nero’s Army. Dioscorides wrote De Materia Medica, a 5-volume encyclopedia about herbal medicine and related medicinal substances (a pharmacopeia), that was widely read for more than 1,500 years. In it, he wrote of a root known as rha or rheon, which came from the Bosphorus, or the Instanbul Strait, the winding strait that separates Europe and Asia.

Rhubarb was given to the Wu emperor of the Liang dynasty in China (reign: 557-579) to cure his fever. It was sent to the throne as tributes from the southern parts of China during the Tang dynasty (618-907). During the Song dynasty (960-1127) rhubarb was taken in times of plague. A Christian sentenced to a hard punishment during the Yuan dynasty (1115-1234)  was pardoned after using previously collected rhubarb to heal some soldiers.

Although various types of rhubarb grow in different parts of the world (Altay, Siberia, the Himalayas, Tibet, and Mongolia), true rhubarb, which provided the laxative effect, is the Chinese variety (Rheum palmatum), which grows only in Ama Surga and Dsun-molun, in the mountainous regions of Gansu province in China.

Marco Polo (c.1254 – January 8–9, 1324), discussed Chinese rhubarb at length in the accounts of his travels in China. In those days, Venice was an extremely important trading center. Because of eastern Arabic influence, Chinese rhubarb was already widely used in European medicine, especially at the medical school of Salerno. It was imported along the Silk Road, through the ports of Aleppo and Smyrna, and becoming known as “Turkish rhubarb.”

Rhubarb was mostly unknown in Britain until the 14th century, when it was alleged that it purified the blood and made young wenches look fair. At that time, the price of rhubarb root was even more than opium. In France, it was 10 times the price of cinnamon, and four times the price of saffron, which at the time was the most expensive spice. Because it was so valuable to pharmacists and physicians in their treatment of most ailments, anyone who could cultivate high-quality Chinese rhubarb in Europe stood to make a fortune.

The value of rhubarb can be seen in Ruy Gonzáles de Clavijo’s report of his embassy in 1403-05 to Timur in Samarkand (in present-day Kazakhstan): “The best of all merchandise coming to Samarkand was from China: especially silks, satins, musk, rubies, diamonds, pearls, and rhubarb…”

The popular edible species of rhubarb, Rheum rhaponticum, most likely originated in Mongolia or Siberia. It was introduced to Europe by Italian botanist Prosper Alpinus in 1608 as a substitute for Chinese rhubarb, whose roots continued to be used medicinally.

The Guangzong emperor of China (1620-1621) was said to have been miraculously cured by rhubarb from some severe illness he contracted after an encounter with four “beautiful women” sent to him by a high official. Near the end of the Ming dynasty (1644) a Ming general tried (in vain) to commit suicide by eating rhubarb. In 1759 the Qianlong emperor of the Qing dynasty forbade export of tea and rhubarb to the Russians after a border conflict in the north part of China.

Hannah Glasse published what is believed to be one of the first recipes in print for rhubarb pie in 1760, 13 years after her other famous first, the recipe for Yorkshire Pudding. Her recipe in the Compleat Confectioner tells of cutting the stalks of English rhubarb to the size of gooseberries, sweetening them, and preparing them as you would a gooseberry tart.

Scotsman James Mounsey had been the doctor to tsar Peter III, but following the tsar’s assassination in 1762, Mounsey fled for his life back to Lockerbie in Dumfriesshire.  He brought seeds of R. rhaponticum with him and from these he successfully grew fields of high-quality rhubarb. Specimens of R. palmatum were raised from seed as early as 1764 in the Botanical Gardens in Edinburgh, although they were not grown for very long in Scotland for medicinal purposes, because their roots were susceptible to rot in the Scottish climate.

On March 12, 1770, John Ellis, the Agent for West Florida in London, sent rhubarb seeds to the Hon. James Habersham in Savannah, Georgia. The seeds were received on July 10, 1770. Habersham distributed the seeds to several of the best horticulturalists in the area and among them was Samuel Bowen, who also planted the first soybeans in America. Ben Franklin obtained rhubarb seeds from Scotland and sent them to John Bartram in Philadelphia in 1772.

Around 1777, William Hayward, an apothecary, of Banbury, in Oxfordshire, began cultivating rhubarb with plants of R. rhaponticum, raised from the seeds brought from Russia in 1762, and produced a medical-quality rhubarb, which was sold as “genuine rhubarb” by men dressed up as Turks. In 1778,  rhubarb was recorded as a food plant in Europe. The earliest known use of rhubarb as a food appeared as a filling for tarts and pies. Some suspected that this was a hybrid of the Chinese variety of rhubarb. In 1790 the same Qianlong emperor of the Qing dynasty who forbade export of tea and rhubarb to the Russians in 1759 declared that the Western countries would have to do without Chinese rhubarb. In 1793, William Hayward was awarded a silver medal by the Royal Society for the “Cure and Culture of Rhubarb.” When Hayward died in 1811, he left his rhubarb plantations to Peter Usher (ca 1775 – 1852), a Unitarian minister.

By 1822, rhubarb was sold in produce markets in Massachusetts. The modern market for culinary rhubarb was created virtually from scratch in 1824 by Joseph Myatt, a South London nurseryman best known for producing strawberries. Myatt took some rhubarb plants and a recipe for tarts, and convinced others that the otherwise bitter rhubarb could taste good when combined with strawberries and a little sugar.  The timing was perfect, because sugar was becoming available and affordable. Adding to rhubarb’s popularity was the fact that it is generally ready for harvest well before most other vegetables. With forcing, it can be made available even earlier.  It was a welcome, early spring food after a long winter.  With its explosion in popularity, people developed many other preparation and preservation techniques for rhubarb, including drying, canning, and eventually, freezing.

In 1828 the Daoguang emperor of China, grandson of the Qianlong emperor, sent out an edict declaring that no more tea or Chinese rhubarb would be sold to the “barbarians.”

Queen Victoria’s crowning in 1837 was celebrated with the introduction of the Victoria variety of rhubarb. Victoria rhubarb was easy to grow, reliably robust, and consistently sweet and tender. It was enormously popular from the start, and launched the Victorian obsession with rhubarb.

The imperial commissioner, Lin Zexu, who was sent to Canton in 1839 to put an end to the opium trade, wrote a letter to Queen Victoria pointing to the “fact” that the foreign barbarians surely would die if they could not obtain tea and rhubarb from China and that the Queen for this reason should stop the wicked British merchants from trading in opium. There is no evidence that Victoria ever had the letter translated and read for her, and when Lin Zexu wrote to the British merchants in Canton later that same year, telling them that a stop to the Chinese rhubarb trade would mean the death for the pitiful foreigners, the British government responded with canon boats from India.

Peter Usher eventually handed over his Banbury rhubarb fields to his son William Rufus Usher, in 1845, and sailed off to America, age 70, with his third wife to join another son who was already there. He died in Ohio in 1852. R. officinale is also now cultivated in Banbury, from specimens first introduced into England in 1873. Both R. rhaponticum and R. officinale are currently grown in Oxfordshire and in Bedfordshire.

In the late 19th century, rhubarb was brought to Alaska by the Russians and used as an effective counter-agent for scurvy. By the early 20th century, its popularity was firmly entrenched in the New England states where it was used as pastry and pie fillings and also to make homemade wine.

Rhubarb’s popularity declined dramatically during World War II, possibly as a direct result of the rationing of sugar during the war. Since World War II, rhubarb production has rebounded, but to only a fraction of pre-war levels.

A New York court decided in 1947 that because rhubarb was used in the United States as a “fruit,” it counted as a fruit for the purposes of regulations and duties. A side effect was a reduction on imported rhubarb tariffs, as tariffs were higher for vegetables than fruits.

Today’s United States rhubarb production is almost exclusively outdoors with relatively little commercial forcing. There are about 1300 acres devoted to rhubarb production, 60% in Washington State with Oregon and California next, and 1/2 acre in Black Forest, Colorado.  Rhubarb production also resumed in England after the war but, as in the United States, not at “mania” levels. Forcing, however, is still popular in England with Yorkshire the English leader in rhubarb production.

Rhubarb leaves are toxic and have no safe culinary use for humans. This is due to high concentrations of oxalic acid, phytochemical found in many plants, but present in extreme amounts in rhubarb leaves. Other toxins may also exist; however, based on oxalic acid alone, 5 kilograms (11 pounds) of the leaves provide a lethal dose to a human, although this varies by variety and the phase of growth.

Rhubarb can:

  1. Fight free radicals. As a rich source of vitamin C and anthraquinones, rhubarb is a potent antioxidant. Antioxidants help rid your body of free radicals, which are byproducts of metabolism that can attack healthy body tissue, causing many serious disease processes, including heart disease and cancer. The manganese in rhubarb is a co-factor for the antioxidant enzyme, superoxide dismutase. Catechins in rhubarb are potent antioxidants that can prevent tumor blood vessel growth, protect against the development of atherosclerotic plaque buildups in arteries, help promote anti-diabetic effects in insulin resistance, and provide significant protection against Parkinson’s and Alzheimer’s diseases.
  2. Fight cancer. The anthraquinones in rhubarb inhibit cancer growth and kill cancer cells. They also help to prevent metastases, which are secondary cancers that appear as a result of the primary cancer. The vitamin C in rhubarb also helps lower your cancer risk. Aloe-emodin in rhubarb can arrest the cell cycle in cancer cell lines. Emodin inhibits human cancer cell invasiveness. Oxalic acid in rhubarb is believed to be successful in fighting several kinds of tumor cells.
  3. Lower blood pressure. The chemical properties of rhubarb cause the smooth muscle of your blood vessels to relax and dilate, resulting in lower blood pressure. Potassium in rhubarb lowers blood pressure by counteracting the detrimental effects of sodium and regulating fluid balance. High blood pressure is a precursor to many serious diseases, including heart disease.
  4. Lower cholesterol. The high fiber content of rhubarb reduces low-density lipoprotein (LDL or ” bad”) cholesterol levels in your blood. LDL cholesterol from high-fat diets causes the build-up of fatty plaques on the walls of your arteries. Initially these fatty plaques cause high blood pressure because your heart has to work so much harder to pump blood through these arteries. Eventually these fatty plaques can completely close off the flow of blood through them leading to heart attack or stroke.
  5. Fight chronic inflammation. Emodin and lindeyin in rhubarb may fight chronic inflammation, which is a precursor to many diseases, including heart disease and cancer.
  6. Fight pathogens. In the laboratory, anthraquinone in rhubarb kills the viruses responsible for cold sores, measles, polio, and influenza, and the rhein component of rhubarb killed Bacteroides fragilis and other bacteria. The high vitamin C content can also help to ward off colds and influenza as well as reduce intensity of symptoms and reduce recovery times.
  7. Prevent constipation. Eating rhubarb regularly can help prevent constipation. At higher doses the hydrolyzed metabolites of emodin and sennidin in rhubarb stimulate peristalsis (the contraction and relaxation of your digestive tract that moves food into and wastes out of your system), encourage water absorption into the large intestine for a softer stool, and act as a laxative. The high fiber content of rhubarb also helps keep bowel movements regular. When used in very small doses, the tannin content in rhubarb can stop diarrhea.

Nutrients in 100 Grams of Raw Rhubarb

Nutrient

Amount

Daily Value

vitamin C

8 mg

13%

manganese

0.2 mg

10%

calcium

86 mg

9%

potassium

288 mg

8%

fiber

1.8 g

7%

copper

0.131 mg

6.6%

magnesium

12 mg

3%

vitamin A

102 IU

2%

folate

7 µg

2%

carbohydrates

4.5 g

2%

selenium

1.1 µg

2%

protein

0.9 g

2%

riboflavin

0.030 mg

2%

Calories

21

1%

phosphorus

14 mg

1%

niacin

0.3 mg

1%

iron

0.2 mg

1%

zinc

0.1 mg

1%

vitamin B6

0.024 mg

1%

thiamine

0.02 mg

1%

fat

0.2 g

0.3%

pantothenic acid

0.1 mg

0.1%

sodium

4 mg

0.017%

Hothouse rhubarb is available most of the year, while field-grown stalks are available in early spring. The Pacific Northwest has a second harvest of rhubarb between June and July.

When selecting rhubarb, look for stalks that are heavy and crisp with taut, shiny skin. Avoid rubbery, fibrous, dry stalks.

At home, wash the stalks well and trim off the dry ends and leaves, and store loosely covered in the crisper drawer.

Rhubarb leaves contain high levels of oxalic acid and a more potent, unidentified toxin, so trimming and discarding them is essential. Don’t peel the fibrous skin as you chop the stalks, because the skin contains lots of color and flavor. For a simple snack, dip pieces of rhubarb in maple syrup or agave nectar.

When rhubarb is cooked, its juices thicken, and it disintegrates into shreds of translucent fibers. Heavily cooked rhubarb has the perfect consistency for jams, chutneys, and compotes, but isn’t so attractive when stir-fried or arranged on a tart. Quick heat yields tender but cohesive rhubarb pieces with rich flavor and a natural, glossy sheen.

Try rhubarb in one of these recipes:


This blog uses the latest nutritional data available from the USDA (United States Department of Agriculture), and the FDA (United States Food and Drug Administration), as well as nutritional data provided by food growers and manufacturers about their products. We believe the information on this website to be accurate. However, we are not responsible for typographical or other errors. Nutrition information for recipes is calculated by Living Cookbook based on the ingredients in each recipe based on statistical averages. Nutrition may vary based on methods of preparation, origin and freshness of ingredients, and other factors.

This blog is not a substitute for the services of a trained health professional. Although we provide nutritional information, the information on this blog is for informational purposes only. No information offered by or through this blog shall be construed as or understood to be medical advice or care. None of the information on this blog should be used to diagnose or treat any health problem or disease. Consult with a health care provider before taking any product or using any information on this blog. Please discuss any concerns with your health care provider.

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