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Rhubarb
Rhubarb is the fleshy, edible stalks ( petioles) of species and hybrids (culinary rhubarb) of ''Rheum'' in the family Polygonaceae, which are cooked and used for food. The plant is a herbaceous perennial that grows from short, thick rhizomes. Historically, different plants have been called "rhubarb" in English. The large, triangular leaves contain high levels of oxalic acid and anthrone glycosides, making them inedible. The small flowers are grouped in large compound leafy greenish-white to rose-red inflorescences. The precise origin of culinary rhubarb is unknown. The species '' Rheum rhabarbarum'' (syn. ''R. undulatum'') and '' R. rhaponticum'' were grown in Europe before the 18th century and used for medicinal purposes. By the early 18th century, these two species and a possible hybrid of unknown origin, ''R.'' × ''hybridum'', were grown as vegetable crops in England and Scandinavia. They readily hybridize, and culinary rhubarb was developed by selecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rheum Rhaponticum
''Rheum rhaponticum'', the false rhubarb, rhapontic rhubarb or rhapontic, is a plant species in the genus ''Rheum'' found in the wild. It is the only ''Rheum'' species found only in Europe, and is now restricted to the Rila mountain range in south-western Bulgaria. It was introduced to other countries in Europe. It is considered to be one of the parents of the modern culinary rhubarb. Description ''Rheum rhaponticum'' is a robust perennial herbaceous plant growing from a woody rhizome. It has large, undivided leaves, with succulent petioles (stalks). The blade of the leaf is up to 50 cm long, and is wider than its length. The leaves are heart-shaped at the base with five prominent nerves. The petioles are concave above and convex below, with about 10 ridges. The flowers are borne in a panicle and are light greenish-yellow in colour. The fruits have membrane-like wings and are about 5 mm long on pedicels (stems) of the same length. Karyotypy In 1928, Jaretzky found ''R. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rheum (plant)
''Rheum'' is a genus of about 60 herbaceous perennial plants in the family Polygonaceae. Species are native to eastern Europe, southern and eastern temperate Asia, with a few reaching into northern tropical Asia. ''Rheum'' species are cultivated in Europe, Asia, and North America. The genus includes the vegetable rhubarb. The species have large somewhat triangular shaped leaves with long, fleshy Petiole (botany), petioles. The flowers are small, greenish-white to rose-red, and grouped in large compound leafy inflorescences. Many rhubarb cultivars have been domesticated as medicinal plants and for human consumption. While the leaves are slightly toxic, the stalks are used in pies and other foods for their tart flavour. Description ''Rheum'' species are herbaceous perennials growing from fleshy roots. They have upright growing stems and mostly basal, deciduous leaves growing from short, thick rhizomes. They have persistent or deciduous ocrea. The inflorescences are terminal and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rheum Rhabarbarum (Rabarber) Frambozenrood Bloeiwijze
''Rheum rhabarbarum'' is a species of flowering plant in the family Polygonaceae, native to a region stretching from southern Siberia to north and central China. It has been harvested from the wild for centuries for its root, which was harvested for use as a popular medicine in Europe and Asia. It was later cultivated for its root in England and Russia. It is considered to be one of the species involved in the development of culinary rhubarb, for which the scientific name ''R. rhabarbarum'' is sometimes (erroneously) used. Taxonomy ''Rheum rhabarbarum'' was first described by Carl Linnaeus in 1753. Linnaeus also described ''R. undulatum'', but this is now considered to be the same species. The name ''rha barbarum'', Latin for 'foreign rha', was first used in the writings of Celsus, who uses the word to describe a valued medicinal root imported from the east. Description Similar species According to the 2003 key in the ''Flora of China'', this species is distinguished f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petiole (botany)
In botany, the petiole () is the stalk that attaches the leaf blade to the Plant stem, stem. It is able to twist the leaf to face the sun, producing a characteristic foliage arrangement (spacing of blades), and also optimizing its exposure to sunlight. Outgrowths appearing on each side of the petiole in some species are called stipules. The terms wikt:petiolate, petiolate and wikt:apetiolate, apetiolate are applied respectively to leaves with and without petioles. Description The petiole is a stalk that attaches a leaf to the plant stem. In petiolate leaves the leaf stalk may be long (as in the leaves of celery and rhubarb), or short (for example basil). When completely absent, the blade attaches directly to the stem and is said to be Sessility (botany), sessile or apetiolate. Subpetiolate leaves have an extremely short petiole, and may appear sessile. The broomrape family Orobanchaceae is an example of a family in which the leaves are always sessile. In some other plant group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxalic Acid
Oxalic acid is an organic acid with the systematic name ethanedioic acid and chemical formula , also written as or or . It is the simplest dicarboxylic acid. It is a white crystalline solid that forms a colorless solution in water. Its name is derived from early investigators who isolated oxalic acid from flowering plants of the genus '' Oxalis'', commonly known as wood-sorrels. It occurs naturally in many foods. Excessive ingestion of oxalic acid or prolonged skin contact can be dangerous. Oxalic acid is a much stronger acid than acetic acid. It is a reducing agent and its conjugate bases hydrogen oxalate () and oxalate () are chelating agents for metal cations. It is used as a cleaning agent, especially for the removal of rust, because it forms a water-soluble ferric iron complex, the ferrioxalate ion. Oxalic acid typically occurs as the dihydrate with the formula . History The preparation of salts of oxalic acid from plants had been known since at least 1745, when ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizome
In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and Shoot (botany), shoots from its Node (botany), nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow horizontally. The rhizome also retains the ability to allow new shoots to grow upwards. A rhizome is the main stem of the plant that runs typically underground and horizontally to the soil surface. Rhizomes have nodes and internodes and auxiliary buds. Roots do not have nodes and internodes and have a root cap terminating their ends. In general, rhizomes have short internodes, send out roots from the bottom of the nodes, and generate new upward-growing shoots from the top of the nodes. A stolon is similar to a rhizome, but stolon sprouts from an existing stem having long internodes and generating new shoots at the ends, they are often also called runners such as in the strawberry plant. A stem tuber is a thickene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaf
A leaf (: leaves) is a principal appendage of the plant stem, stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the Shoot (botany), shoot system. In most leaves, the primary Photosynthesis, photosynthetic Tissue (biology), tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf, but in some species, including the mature foliage of ''Eucalyptus'', palisade mesophyll is present on both sides and the leaves are said to be isobilateral. The leaf is an integral part of the stem system, and most leaves are flattened and have distinct upper (Glossary of botanical terms#adaxial, adaxial) and lower (Glossary of botanical terms#abaxial, abaxial) surfaces that differ in color, Trichome, hairiness, the number of stomata (pores that intake and output gases), the amount and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fruit
In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propagated using the movements of humans and other animals in a symbiotic relationship that is the means for seed dispersal for the one group and nutrition for the other; humans, and many other animals, have become dependent on fruits as a source of food. Consequently, fruits account for a substantial fraction of the world's agricultural output, and some (such as the apple and the pomegranate) have acquired extensive cultural and symbolic meanings. In common language and culinary usage, ''fruit'' normally means the seed-associated fleshy structures (or produce) of plants that typically are sweet (or sour) and edible in the raw state, such as apples, bananas, grapes, lemons, oranges, and strawberries. In botanical usage, the term ''fruit'' als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crumble
A crumble (British English) or crisp (American English) is a dessert with a crumbly cake-like topping, sometimes with oats, baked over a fruit filling. Apple and rhubarb are two popular varieties. Savoury fillings such as meat, cheese or vegetables may alternatively be used. As a dessert, crumbles are traditionally served with custard, cream, or ice cream. An apple crumble recipe involving a simple streusel topping appeared in the Canadian ''Farmer's Magazine'' in February 1917. British chef and food writer Hugh Fearnley-Whittingstall describes crumbles as a "national institution" that became popular in Britain since World War II, the topping being easier to prepare than pastry. Crumbles in varying forms are common in Britain, Ireland, and across the Commonwealth of Nations. While the dish is also found in the US, the most common variant is known as an "apple crisp" in American English.Ezinearticles.com Jason McDonald, December 29, 2008; CanadianLiving, July 6, 2015 See also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthrone
Anthrone is a tricyclic aromatic ketone. It is used for a common cellulose assay and in the colorimetric determination of carbohydrates. Derivatives of anthrone are used in pharmacy as laxative. They stimulate the motion of the colon and reduce water reabsorption. Some anthrone derivatives can be extracted from a variety of plants, including '' Rhamnus frangula'', '' Aloe ferox'', '' Rheum officinale'', and '' Cassia senna''. Glycosides of anthrone are also found in high amounts in rhubarb leaves, and alongside concentrated amounts of oxalic acid are the reason for the leaves being inedible. Synthesis and reactions Anthrone can be prepared from anthraquinone by reduction with tin or copper. An alternative synthesis involves cyclization of ''o''-benzylbenzoic acid induced with hydrogen fluoride Hydrogen fluoride (fluorane) is an Inorganic chemistry, inorganic compound with chemical formula . It is a very poisonous, colorless gas or liquid that dissolves in water to yield hy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taste
The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste. Taste is the perception stimulated when a substance in the mouth biochemistry, reacts chemically with taste receptor cells located on taste buds in the oral cavity, mostly on the tongue. Taste, along with olfaction, the sense of smell and trigeminal nerve stimulation (registering texture, pain, and temperature), determines Flavoring, flavors of food and other substances. Humans have taste receptors on taste buds and other areas, including the upper surface of the tongue and the epiglottis. The gustatory cortex is responsible for the perception of taste. The tongue is covered with thousands of small bumps called lingual papillae, papillae, which are visible to the naked eye. Within each papilla are hundreds of taste buds. The exceptions to this is the filiform papillae that do not contain taste buds. There are between 2000 and 5000Boron, W.F., E.L. Boulpaep. 200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
