
Rhubarb
rhubarbe (French), Rhabarber (German), rabarbaro (Italian), ruibarbe (Catalan), ruibarbo (Spanish/Portuguese), rabarber (Dutch), rabarber (Danish/Swedish), rabarbra (Norwegian), raparperi (Finnish), reven (Russian/Bulgarian), rabarbar (Polish), rebarbarabor (Hungarian), rubarbura (Romanian), reon (Greek), rabarbara (Serbo-Croat), ravent (Turkish), ribas (Hebrew), rawand (Arabic), riwand (Persian), daio (Japanese)
The Polygonaceae family includes about thirty genera and 750 species. The most important members are buckwheat, sorrel, and rhubarb.
Rhubarb is the edible stalk of several related species. Botanically, it is classified as a vegetable. However, in 1947, the US Customs Court at Buffalo, NY, ruled it a fruit since that is how it is normally eaten.
The wild plants are all native to Asia. They prefer a cool climate, and flourish especially well in the general area of Mongolia and Siberia and near the Himalayas, where the rhizomes and crowns survive in the frozen ground all winter.
Several of the species are inedible or used only for medicines.
The ones of interest in the kitchen are R. rhaponticum
and R. x hybridum,
which belong to such places such as Mongolia and Siberia.
A species of the Near East, R. ribes,
is probably the one known in classical times. The Greek writer, Dioscorides, stated that the plant “rha” grew in the regions beyond the Bosphorus which was inhabited by barbarians. For this reason, it was subsequently called “rha-ponticum” or “rha-barbarum“.
The traditional role of rhubarb was first and foremost that of a medicine. The Chinese called it by such composite and descriptive names as “ta hwan” (the great yellow one), indicating a “recent” (possibly 4,000 years ago) knowledge of the plant, as all the plants they knew from ancient times have a root word of a single syllable.
By about 200 BC, they knew to call Chinese rhubarb, R. officinale, and valued it medicinally. It later became an important article of trade from China to western Asia and to Arab countries.
In England, it was originally grown as a powerful pergative, and imports for this purpose were estimated to be £200,000 at the time. The purgative principle in rhubarb is caused by a group of substances allied to chrysophanic acid, being present mainly in the root. The dried root
was a popular remedy for a wide range of ills, and its monetary value rivaled that of expensive spices.
In 1542, rhubarb sold in France for ten times the cost of cinnamon; and, in 1657, the English price was almost three times that of opium.
Shipped from China through Russia to Europe, the Latin names were acquired en route, with a long etymological history in Greece, Latin, and Old French.
The garden or culinary rhubarb is not the same as the medicinal varieties;
but it was also developed in the East, where it was used in drinks and meaty stews.
Culinary rhubarb was used in Italy in the late 17th century and by the French, who used it for making tarts and pies, in 1778. The first recipe to appear in England was in 1783 when John Farley (The London Art of Cookery) advocated slicing the stalks and then cooking them with gooseberries.
Rhubarb was intoduced into Maine from Europe around 1790, and from there spread to market gardens around New England and Massachusetts. Utica, Michigan, declares itself to be the “rhubarb capital of the world”.
Rhubarb contains few calories, however. Much sweetener needs to be added to make it palatable, thus destroying this advantage. It also contains significant amounts of calcium, potassium, and thiamin, as well as having laxative properties.
Rhubarb wilts easily if left in the refrigerator, but it does freeze well for later use. It also makes wonderful pies, crisps, puddings, sauces and jams.
Only the stalks are eaten as a food. The leaves are poisonous, as they contain high amounts of oxalic acid. The stalks also contain oxalic acid, but the amount is no greater than that present in spinach and chard, dissipating when cooked. The central ribs of the leaves contains much more and should not be eaten.
Early rhubarb has light red flesh, a green stalk-end, and a mild flavour. The maincrop has dark red flesh and is tangier-tasting. Generally, the redder the flesh, the less oxalic acid it contains.
Depending on the variety, the stalks range from green to purplish-pink; but the forced varieties have spindly, tender bright pink or red stems and crowned with yellow leaves, making their flavour sweeter.
The forcing of rhubarb to produce fruit out of season is done either by covering the plant with a pot to encourage growth in the spring or by the modern method of hothouse cultivation.
The practice has been observed in Afghanistan as well as in Western countries where it was accidentally discovered at the Chelsea Physic Garden early in the 19th century when crowns were covered in debris as a ditch was being cleared. Fortunately, a cleaner method is now used with terracotta jars.
In Britain, the best and sweetest variety, Hawkes Champagne,
comes very early and has thin, tender stalks. By comparison, the unforced summer rhubarb is coarse and sour.
A great range of cultivars are found, including the following:
Crimson red
has a sharp distinctive, but sweet, flavour.
Early champagne or Early red
produces long delicious scarlet stalks.
Glaskin’s perpetual
is vigorus and tasty, and crops over a long period of time.
Sutton was introduced by Suttons Seeds in 1893, and remains a tasty choice.
Timperley early
is a very early vigorous variety.
Valentine
has tender rose-coloured stalks, with a wonderful flavour, perfect for pies or jams.
Victoria
is an old reliable variety that varies in size.
Zwolle seedling has good flavour and fragrance, and stays firm when cooked.